A highly sealed lithium battery steel shell

Abstract

The present application discloses a highly sealed lithium battery steel shell, which belongs to the field of lithium battery technology and is used to improve the sealing of the lithium battery steel shell and increase the safety of the lithium battery. The steel shell comprises a steel shell body, a positive electrode packaging shell, an insulating sleeve and a reinforcement sleeve. The utility model designs a reinforcement sleeve structure, wherein the reinforcement sleeve is used to strengthen the connection strength between the steel shell body and the positive electrode packaging shell to ensure that the two are not easily deformed, and the reinforcement sleeve forms a sealing structure with the steel shell body and the positive electrode packaging shell, so that the lithium battery steel shell has a strong sealing property, and the safety of the lithium battery is increased during the use of the lithium battery.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and in particular to a highly sealed lithium battery steel shell. Background Art

[0002] Cylindrical lithium batteries mostly use steel materials with strong physical stability as the outer shell material, that is, lithium battery steel shell; after the lithium battery has been used for a period of time, due to various reasons, the inside will expand to a certain extent, which places high requirements on the sealing of the lithium battery steel shell.

[0003] However, the existing lithium battery steel shell has the following defects: for example, the connection structure between the positive electrode packaging shell and the lithium battery steel shell is unstable, it will deform when subjected to expansion force, and the sealing performance is insufficient, which will also cause electrolyte leakage, battery short circuit and other problems, which is not conducive to the safe use of lithium batteries. Summary of the invention

[0004] The purpose of this application is to improve the sealing of the lithium battery steel shell and increase the safety of the lithium battery.

[0005] In order to achieve the above objectives, the technical solution adopted in this application is:

[0006] A highly sealed lithium battery steel shell, comprising:

[0007] A steel shell body, wherein the top end of the steel shell body is open;

[0008] A positive electrode packaging shell, the positive electrode packaging shell is fixedly installed on the inner side of the steel shell body through an insulating sleeve;

[0009] A reinforcement sleeve, wherein an annular recessed portion is provided on the side of the steel shell body and near the top, the reinforcement sleeve is arranged on the outside of the steel shell body, and the reinforcement sleeve is located above the annular recessed portion, the top of the reinforcement sleeve has a second ring portion extending vertically inward, the second ring portion is pressed on the top of the steel shell body, the top of the insulating sleeve, and the top of the positive electrode packaging shell, and the bottom end of the reinforcement sleeve has an undercut, and the undercut is stuck in the annular recessed portion of the steel shell body;

[0010] The reinforcement sleeve is made of hard insulating material.

[0011] Preferably, a limiting ring seat is provided inside the annular recess and below the undercut.

[0012] Further preferably, an inner ring is provided on the inner side of the undercut, and a notch is provided on the side of the undercut, and the inner ring is fixed to the limiting ring seat by welding at the notch.

[0013] As another preferred embodiment, the insulating sleeve is located on the inner side of the steel shell body, and a third ring portion is vertically extended inward from the top of the insulating sleeve, a separator ring is vertically extended upward from the inner edge of the third ring portion, a third step is formed above the third ring portion and outside the separator ring, a first ring portion is vertically extended inward from the top of the steel shell body, and the first ring portion is stuck at the third step;

[0014] A first step and a second step are arranged at the top of the positive electrode packaging shell and near the outer edge, the first step is located outside the second step, the third ring portion is clamped at the first step, and the second ring portion is clamped at the second step.

[0015] As another preferred embodiment, the insulating sleeve is fixed to the steel shell body by glue.

[0016] Further preferably, the bottom end of the steel shell body is integrally sealed.

[0017] Further preferably, the outer side surface of the limiting ring seat is a conical surface.

[0018] Further preferably, the limiting ring seat is composed of two semicircular bodies.

[0019] Compared with the prior art, the beneficial effects of this application are:

[0020] (1) The utility model designs a reinforcement sleeve structure, which is used to strengthen the connection strength between the steel shell body and the positive electrode packaging shell to ensure that the two are not easily deformed, and the reinforcement sleeve, the steel shell body and the positive electrode packaging shell form a sealing structure, so that the lithium battery steel shell has strong sealing properties, which increases the safety of the lithium battery during use;

[0021] (2) The utility model provides a stable connection between the reinforcement sleeve and the steel shell body by designing an undercut structure, thereby preventing the reinforcement sleeve from falling off and ensuring the stability of the sealing structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional picture of the steel shell of the strong sealed lithium battery;

[0023] Figure 2 It is a front view of the steel shell of the strong sealed lithium battery;

[0024] Figure 3 for Figure 2 Section view of the section line at AA;

[0025] Figure 4 for Figure 3 A partial enlarged view of point B in the middle;

[0026] Figure 5 A three-dimensional diagram of the steel shell body of the highly sealed lithium battery steel shell;

[0027] Figure 6 A three-dimensional diagram of the reinforcement sleeve of the strong sealed lithium battery steel shell;

[0028] Figure 7 for Figure 6 A partial enlarged view of point C in the middle.

[0029] In the figure: 1, steel shell body; 101, annular recessed portion; 102, first ring portion; 2, positive electrode packaging shell; 201, first step; 202, second step; 3, reinforcement sleeve; 301, second ring portion; 302, undercut; 303, notch; 4, insulating sleeve; 401, third ring portion; 402, separator ring; 403, third step; 5, limiting ring seat; 6, inner ring. DETAILED DESCRIPTION

[0030] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0031] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of narrating the present application and simplifying the 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 cannot be understood as limiting the specific scope of protection of the present application.

[0032] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0033] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0034] like Figure 1-Figure 7 The highly sealed lithium battery steel shell shown includes a steel shell body 1, a positive electrode packaging shell 2 (the positive electrode packaging shell 2 is the topmost structural part of the lithium battery cap, serving as the positive electrode output of the lithium battery), an insulating sleeve 4 and a reinforcement sleeve 3.

[0035] Among them, the top end of the steel shell body 1 is open, and the bottom end of the steel shell body 1 is sealed as a whole, so as to ensure that the steel shell body 1 itself has reliable sealing performance. The positive electrode packaging shell 2 is fixedly installed on the inner side of the steel shell body 1 through the insulating sleeve 4. Generally, the steel shell body 1 can be used as the negative electrode of the lithium battery. Therefore, it is necessary to set an insulating sleeve 4 between the positive electrode packaging shell 2 and the steel shell body 1 to play an isolation role. An annular recessed portion 101 is opened on the side of the steel shell body 1 and close to the top. The reinforcement sleeve 3 is set on the outside of the steel shell body 1. Structural adhesive can be applied between the reinforcement sleeve 3 and the steel shell body 1. The reinforcement sleeve 3 is located above the annular recessed portion 101, and the top of the reinforcement sleeve 3 has a The second ring portion 301 extends vertically inside, and the second ring portion 301 is pressed on the top of the steel shell body 1, the top of the insulating sleeve 4, and the top of the positive electrode packaging shell 2, so as to ensure the structural stability of the positive electrode packaging shell 2 and prevent the positive electrode packaging shell 2 from being pushed upward by high pressure. The second ring portion 301 and the top of the steel shell body 1, the top of the insulating sleeve 4, and the top of the positive electrode packaging shell 2 form a sealing contact surface to achieve strong sealing. The bottom end of the reinforcement sleeve 3 has a buckle 302, and the buckle 302 is stuck in the annular recessed portion 101 of the steel shell body 1. The buckle 302 is stuck in the annular recessed portion 101 of the steel shell body 1 to achieve a stable installation of the reinforcement sleeve 3 and the steel shell body 1.

[0036] The reinforcement sleeve 3 is made of hard insulating material, and may be made of thermosetting plastic, such as PPS.

[0037] In one embodiment, a limiting ring seat 5 is provided inside the annular recess 101 and below the undercut 302. The limiting ring seat 5 presses against the underside of the undercut 302, so that the underside of the undercut 302 is not easily deformed downward, and the undercut 302 will not be easily disengaged.

[0038] In one embodiment, the outer side surface of the limiting ring seat 5 is a conical surface, which corresponds exactly to the inner side surface of the undercut 302. The limiting ring seat 5 is composed of two semicircular bodies so that the limiting ring seat 5 can be stuck in the annular recess 101. After the undercut 302 is installed, the limiting ring seat 5 is located below and inside the undercut 302, thereby avoiding the separation of the two semicircular bodies.

[0039] In one embodiment, an inner ring 6 is provided on the inner side of the undercut 302, and a notch 303 is provided on the side of the undercut 302. The inner ring 6 is welded and fixed to the limiting ring seat 5 at the notch 303. Four notches 303 are generally provided and distributed in a circular array. After the inner ring 6 is welded and fixed to the limiting ring seat 5, the positions of the two semicircular bodies of the limiting ring seat 5 are fixed, and the inner ring 6 and the limiting ring seat 5 clamp the undercut 302 at the upper and lower positions. When the undercut 302 is subjected to an upward force, the inner ring 6 and the limiting ring seat 5 limit the upward movement of the undercut 302, so that the position of the reinforcement sleeve 3 is stable.

[0040] In one embodiment, the insulating sleeve 4 is located on the inner side of the steel shell body 1, and the insulating sleeve 4 is fixedly connected to the steel shell body 1. The top of the insulating sleeve 4 vertically extends a third ring portion 401 inwardly, and the inner edge of the third ring portion 401 vertically extends a separator ring 402 upwardly, and the separator ring 402 is used to isolate the first ring portion 102 and the positive electrode packaging shell 2. A third step 403 is formed above the third ring portion 401 and outside the separator ring 402. The first ring portion 102 vertically extends inwardly from the top of the steel shell body 1, and the first ring portion 102 is stuck at the third step 403, which forms a restriction on the structure of the insulating sleeve 4, thereby ensuring the stability of the structure of the insulating sleeve 4 and preventing the insulating sleeve 4 from sliding up and down relative to the steel shell body 1.

[0041] A first step 201 and a second step 202 are provided at the top and near the outer edge of the positive electrode packaging shell 2 . The first step 201 is located outside the second step 202 . The third ring portion 401 is clamped at the first step 201 , and the second ring portion 301 is clamped at the second step 202 .

[0042] The third ring portion 401 is stuck at the first step 201, which is the first sealing structure in the lithium battery; the second ring portion 301 is stuck at the second step 202, which is the second sealing structure in the lithium battery, thereby ensuring that the lithium battery has strong sealing performance.

[0043] In one embodiment, the insulating sleeve 4 is fixed to the steel shell body 1 by glue, and the bottom end of the insulating sleeve 4 may also be provided with a snap-fitting portion corresponding to the annular recess 101 , thereby ensuring a stable connection between the insulating sleeve 4 and the steel shell body 1 .

[0044] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A highly sealed lithium battery steel shell, comprising a steel shell body and a positive electrode packaging shell, wherein the top of the steel shell body is open, and the positive electrode packaging shell is fixedly installed on the inner side of the steel shell body through an insulating sleeve, characterized in that: Also includes: A reinforcement sleeve, wherein an annular recessed portion is provided on the side of the steel shell body and near the top, the reinforcement sleeve is arranged on the outside of the steel shell body, and the reinforcement sleeve is located above the annular recessed portion, the top of the reinforcement sleeve has a second ring portion extending vertically inward, the second ring portion is pressed on the top of the steel shell body, the top of the insulating sleeve, and the top of the positive electrode packaging shell, and the bottom end of the reinforcement sleeve has an undercut, and the undercut is stuck in the annular recessed portion of the steel shell body; The reinforcement sleeve is made of hard insulating material.

2. The highly sealed lithium battery steel case as claimed in claim 1, characterized in that: A limiting ring seat is arranged inside the annular recess and below the undercut.

3. The highly sealed lithium battery steel case as claimed in claim 2, characterized in that: An inner sleeve ring is arranged on the inner side of the undercut, and a notch is arranged on the side of the undercut. The inner sleeve ring is fixed to the limiting ring seat by welding at the notch.

4. The highly sealed lithium battery steel case as claimed in claim 1, characterized in that: The insulating sleeve is located on the inner side of the steel shell body, and a third ring portion is vertically extended inward from the top of the insulating sleeve, a separator ring is vertically extended upward from the inner edge of the third ring portion, a third step is formed above the third ring portion and outside the separator ring, a first ring portion is vertically extended inward from the top of the steel shell body, and the first ring portion is stuck at the third step; A first step and a second step are arranged at the top of the positive electrode packaging shell and near the outer edge, the first step is located outside the second step, the third ring portion is clamped at the first step, and the second ring portion is clamped at the second step.

5. The highly sealed lithium battery steel case as claimed in claim 1, characterized in that: The insulating sleeve and the steel shell body are fixed by glue.

6. The highly sealed lithium battery steel case as claimed in claim 1, characterized in that: The bottom end of the steel shell body is integrally sealed.

7. The highly sealed lithium battery steel case as claimed in claim 3, characterized in that: The outer side surface of the limiting ring seat is a conical surface.

8. The highly sealed lithium battery steel case as claimed in claim 3, characterized in that: The limiting ring seat is composed of two semicircular bodies.

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