CN216529076U

CN216529076U - Square lithium ion battery shell

Info

Publication number: CN216529076U
Application number: CN202122886214.1U
Authority: CN
Inventors: 陈胜皇; 蒋中磊; 卜大千
Original assignee: Dongguan Weike Battery Co ltd
Current assignee: Dongguan Weike Battery Co ltd
Priority date: 2021-11-23
Filing date: 2021-11-23
Publication date: 2022-05-13
Anticipated expiration: 2031-11-23

Abstract

The utility model discloses a square lithium ion battery shell, which comprises: the battery front cover is connected with the battery rear cover, the battery front cover is provided with a front cover cavity, the battery rear cover is provided with a rear cover cavity, the front cover cavity is communicated with the rear cover cavity to form a battery cell accommodating cavity, and the battery cell accommodating cavity is used for accommodating a battery cell; the periphery of the battery front cover is provided with a front cover edge part, the periphery of the battery rear cover is provided with a rear cover edge part, and the front cover edge part and the rear cover edge part are welded in a seam welding manner; the same front side surface of the battery front cover and the same front side surface of the battery rear cover jointly form a shell head part, the shell head part is provided with a positive pole post and a negative pole post, the shell head part is provided with a liquid injection hole and a thinning area, and the thinning area is positioned between the liquid injection hole and the positive pole post; the thickness of the thinned region is less than the thickness of the housing head. Above-mentioned square lithium ion battery shell through set up between anodal utmost point post and notes liquid hole and cut thin district, has improved the security of battery.

Description

Square lithium ion battery shell

Technical Field

The utility model relates to the technical field of batteries, in particular to a square lithium ion battery shell.

Background

Along with the progress of scientific technology and more diversified customer demands, in the field of intelligent terminals, the diversity of digital products such as smart phones and notebook computers is more and more abundant, and the endurance of the intelligent terminals needs to be supported by batteries, especially lithium ion batteries capable of being charged and discharged, so that the safety, quick charging, high capacity and high cycle of the batteries are the main development directions of the lithium ion batteries. The safety of the battery is more important. The existing digital product is mainly composed of soft package batteries and a small part of 18650 batteries, and the soft package has poor sealing performance and is easy to leak electricity and leak liquid, so that the safety performance of the battery cell is influenced, and the battery cells requiring high safety types cannot be produced in large scale. The steel shell is limited in size and shape, so that the steel shell cannot be suitable for a high-capacity digital battery, and most importantly, thermal runaway easily occurs when the steel shell is in a short circuit, and the shell is exploded due to the fact that the internal pressure is sharply increased, so that the safety of a human body and equipment is affected.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is necessary to provide a square lithium ion battery case for improving the safety of the battery.

A square lithium ion battery shell comprises a battery front cover and a battery rear cover, wherein the battery front cover is connected with the battery rear cover,

the battery front cover is provided with a front cover cavity, the battery rear cover is provided with a rear cover cavity, the front cover cavity and the rear cover cavity are communicated to form a battery cell accommodating cavity, and the battery cell accommodating cavity is used for accommodating a battery cell;

the periphery of the battery front cover is provided with a front cover edge part, the periphery of the battery rear cover is provided with a rear cover edge part, and the front cover edge part and the rear cover edge part are welded in a seam welding manner;

the battery front cover and the same front side surface of the battery rear cover jointly form a shell head part, the shell head part is provided with a positive pole post and a negative pole post, the shell head part is provided with a liquid injection hole and a thinning area, and the thinning area is positioned between the liquid injection hole and the positive pole post;

the thickness of the thinned region is less than the thickness of the housing head.

In one embodiment, the thinned region is diamond, square or circular in shape.

In one embodiment, the thickness of the thinned region is 5-10um less than the thickness of the housing head.

In one embodiment, the width of each of the front cover edge and the rear cover edge is 3-9 mm.

In one embodiment, the width of each of the front cover edge and the rear cover edge is 5 mm.

In one embodiment, the thicknesses of the front cover and the rear cover are respectively 10-40 um.

In one embodiment, the thicknesses of the front cover and the rear cover are 25um respectively.

In one embodiment, the front side surface of the battery front cover is provided with an upper thinning area, the front side surface of the battery rear cover is provided with a lower thinning area, and the edge weld seams of the upper thinning area and the lower thinning area are welded together to form the thinning area.

In one embodiment, the upper thinning-out region and the lower thinning-out region are respectively equilateral triangles.

In one embodiment, the liquid injection hole is formed in the front side surface of the battery rear cover.

According to the square lithium ion battery shell, the thinning area is arranged between the positive pole column and the liquid injection hole, the thickness of the thinning area is smaller than that of other normal areas of the shell head, and when the internal pressure of the battery cell in the battery cell accommodating cavity rises sharply in the using process, high-pressure gas can burst through the thinning area, so that the pressure is released, the explosion of the battery is prevented, and the safety of the battery is improved.

Drawings

FIG. 1 is a schematic diagram of a square lithium ion battery case according to an embodiment;

fig. 2 is a schematic structural diagram of another view angle of the square lithium ion battery case in the embodiment shown in fig. 1;

fig. 3 is a schematic structural diagram of another view angle of the square lithium ion battery case in the embodiment shown in fig. 1;

FIG. 4 is a schematic diagram of a disassembled structure of a square lithium ion battery case in one embodiment;

fig. 5 is a schematic view of another perspective disassembled structure of a square lithium ion battery case according to an embodiment.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the utility model and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the utility model.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1 to 5, the present invention provides a square lithium ion battery case 10, where the square lithium ion battery case 10 includes a front battery cover 110 and a rear battery cover 120, the front battery cover 110 is connected to the rear battery cover 120, the front battery cover 110 is provided with a front cover cavity 111, the rear battery cover 120 is provided with a rear cover cavity 121, the front cover cavity 111 and the rear cover cavity 121 are communicated to form a battery cell receiving cavity 130, and the battery cell receiving cavity 130 is used for receiving a battery cell. The periphery of the battery front cover 110 is provided with a front cover edge part 112, the periphery of the battery rear cover 120 is provided with a rear cover edge part 122, and the front cover edge part 112 and the rear cover edge part 122 are welded together; the same front side surface of the front battery cover 110 and the same front side surface of the rear battery cover 120 jointly form a casing head 140, the casing head 140 is provided with a positive pole 141 and a negative pole 142, the casing head 140 is provided with a liquid injection hole 143 and a thinning area 144, and the thinning area 144 is positioned between the liquid injection hole 143 and the positive pole 141; the thinned region 144 has a thickness less than the thickness of the housing head 140.

In the square lithium ion battery case 10, the thinned region 144 is arranged between the positive electrode post 141 and the liquid injection hole 143, and the thickness of the thinned region is thinner than that of other normal regions of the case head 140, so that when the internal pressure of the battery cell in the battery cell accommodating cavity 130 is increased rapidly in the using process, high-pressure gas can burst through the thinned region 144, the pressure is released, the explosion of the battery is prevented, and the safety of the battery is improved. In particular, when the front cover 110 and the rear cover 120 are made of steel, the thinned region 144 of the prismatic lithium ion battery case 10 greatly improves the safety performance in case of emergency such as short circuit or impact.

The battery front cover 110 and the battery rear cover 120 are respectively deeply punched with grooves capable of accommodating the battery cell to respectively form a front cover cavity 111 and a rear cover cavity 121, the deeply punched battery front cover 110 and the battery rear cover 120 are processed with positive and negative poles and liquid injection holes 143 on the side edges, the processed battery front cover 110 and the processed battery rear cover are manufactured with laser to form a thinning area 144, then the wound battery cell is placed into a shell, and other processes are finished according to the production of a normal square lithium ion battery process.

In one embodiment, the skived zone 144 has a diamond, square or circular shape. In the embodiment shown in fig. 1-5, the skived zone 144 is diamond shaped. It can be understood that the rhombus is cut thin the district and is cut the shape of thin district and set up to the rhombus, and the advantage lies in that the rhombus is cut thin the district and has a plurality of corners, and the metal tension of corner is less, in case meet inside electric core short circuit or external force striking and lead to the electric core explosion, rhombus is cut thin the district and can be broken fast to can release the inside pressure of battery case effectively in the short time, when guaranteeing that the inside short circuit of electric core etc. is unusual, prevent to injure people's scheduling problem because of the explosion that the pressure gathering arouses.

In one embodiment, the front side of the front cover 110 is formed with an upper thinning region, the front side of the rear cover 120 is formed with a lower thinning region, and the edges of the upper thinning region and the lower thinning region are welded together to form the thinning region 144. Optionally, the stitch welding is performed by laser welding. Therefore, the thinning area formed after the stitch welding has the same strength as the integrally formed thinning area, and the process is convenient to realize.

In one embodiment, the upper thinning-out region and the lower thinning-out region are respectively equilateral triangles. Thus, the edge weld of the upper and lower thinned regions can form a diamond-shaped thinned region after welding. In other embodiments, the upper thinning area and the lower thinning area may also be a semicircle or a half frame, respectively, to form a round or square thinning area.

In one embodiment, the thinned region 144 has a thickness that is 5-10um less than the thickness of the housing head 140. That is, the diamond-thinned region is 5-10um thinner than the other normal regions of the housing head 140. Optionally, the thickness of the thinned region 144 is less than 5um compared to the thickness of the housing head 140. Optionally, the thickness of the thinned region 144 is less than 10um compared to the thickness of the housing head 140. Optionally, the thickness of the thinned region 144 is 8um less than the thickness of the housing head 140. It can be understood that the selection of the thickness of the thinning region 144 may be correspondingly set according to the cell capacity, for example, when the cell capacity is large, the thickness of the thinning region 144 may be appropriately increased, so that abnormal damage may be avoided, that is, damage may not be caused by internal cell short circuit or external force impact, because the thickness of the thinning region 144 is large, the pressure that can be borne is also large, and if the internal cell short circuit or external force impact does not cause cell explosion, the thinning region 144 with a large thickness may bear a large pressure to avoid unnecessary damage.

In one embodiment, the width of each of the front cover edge 112 and the back cover edge 122 is 3-9 mm. Alternatively, the width of each of the front cover edge 112 and the rear cover edge 122 is 5 mm. Alternatively, the width of each of the front cover edge 112 and the rear cover edge 122 is 3 mm. Alternatively, the width of each of the front cover edge 112 and the rear cover edge 122 is 9 mm. The plane of the front cover edge 112 and the plane of the back cover edge 122 are parallel to each other. It will be appreciated that the purpose of the front cover rim portion 112 and the rear cover rim portion 122 is to facilitate the stitch welding for ease of manufacturability.

In one embodiment, the thicknesses of the front battery cover 110 and the rear battery cover 120 are 10-40um, respectively. Alternatively, the thicknesses of the front battery cover 110 and the rear battery cover 120 are 25um, respectively. Alternatively, the thicknesses of the front battery cover 110 and the rear battery cover 120 are 10um, respectively. Alternatively, the thicknesses of the front battery cover 110 and the rear battery cover 120 are 40um, respectively. The front battery cover 110 may be referred to as a front battery cover and may be made of metal, such as steel, and the rear battery cover 120 may be referred to as a rear battery cover and may be made of metal, such as steel, such that the thickness of the case formed by the front battery cover 110 and the rear battery cover 120 is 10-40 um. The thickness is also determined by the capacity of the battery cell, and when the cell capacity is larger, a thicker cover plate can be adopted to improve the safety.

In one embodiment, the injection hole 143 is opened on the front side surface of the battery back cover 120. In one embodiment, the injection hole 143 is opened on the front side surface of the battery front cover 110. In one embodiment, the front side of the front cover 110 has an upper liquid-injecting groove, the front side of the rear cover 120 has a lower liquid-injecting groove, and the upper liquid-injecting groove and the lower liquid-injecting groove are connected to form the liquid-injecting hole 143. It will be appreciated that the design of the fill hole 143 can be customized to the needs of the actual battery.

The utility model has the advantages that: because of the square steel-clad lithium cell's of tradition steel-clad lithium cell steel-clad bulk strength is unanimous basically, when meetting inside electric core short circuit or external impact, causes internal pressure to rise sharply but because of steel-clad bulk strength is unanimous, leads to pressure can't be effectively released to lead to the explosion. The square lithium ion battery shell in each embodiment is improved by the traditional design, and a weak point with lower strength is manufactured at a standard position by the method, so that when the internal short circuit of the battery core and other abnormalities occur, the slurry is flushed away from the weak point to release pressure, and the problems that people are injured by explosion and equipment are damaged due to pressure accumulation are prevented.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A square lithium ion battery shell comprises a battery front cover and a battery rear cover, wherein the battery front cover is connected with the battery rear cover,

2. The prismatic lithium ion battery cell casing of claim 1, wherein the thinned region is diamond, square or circular in shape.

3. The prismatic lithium ion battery cell casing of claim 2, wherein the thickness of the thinned region is 5-10um less than the thickness of the casing head.

4. The prismatic lithium ion battery case according to claim 1, wherein the width of each of the front cover edge portion and the rear cover edge portion is 3 to 9 mm.

5. The square lithium ion battery case according to claim 4, wherein the width of each of the front cover edge portion and the rear cover edge portion is 5 mm.

6. The prismatic lithium ion battery case of claim 1, wherein the thickness of the battery front cover and the battery back cover are 10-40um respectively.

7. The prismatic lithium ion battery case of claim 6, wherein the thickness of the battery front cover and the battery back cover are respectively 25 um.

8. The square lithium ion battery case of claim 1, wherein the front side of the front cover has an upper thinned region, the front side of the rear cover has a lower thinned region, and the upper thinned region and the lower thinned region are welded together by seam welding to form the thinned region.

9. The square lithium ion battery case of claim 8, wherein the upper thinned region and the lower thinned region are each an equilateral triangle.

10. The prismatic lithium ion battery case according to claim 1, wherein the electrolyte injection hole is opened on the front side surface of the battery rear cover.