CN212230462U

CN212230462U - Composite shell structure of button lithium secondary battery

Info

Publication number: CN212230462U
Application number: CN202021129914.5U
Authority: CN
Inventors: 赖秀菱; 施凯胜; 陈福禄; 沈志鸿
Original assignee: Synergy Scientech Corp
Current assignee: Synergy Scientech Corp
Priority date: 2020-06-17
Filing date: 2020-06-17
Publication date: 2020-12-25
Anticipated expiration: 2030-06-17

Abstract

The utility model discloses a button type lithium secondary battery composite shell structure, the structure is used for encapsulating a lithium secondary battery, include an interior casing, an insulating rubber ring and an outer casing, wherein this interior casing has a bottom surface, a rampart of surrounding connection this bottom surface and a accommodation space that is surrounded by this rampart, the lateral surface of this rampart has a plurality of shallow slots, this outer casing then has a closing cap and a cap ring of connecting this closing cap and corresponding this rampart, have a cooperation section on the cap ring, this closing cap of this outer casing shields this accommodation space, and this cap ring interval this insulating rubber ring and seal this accommodation space, in order to utilize this cooperation section to suppress this insulating rubber ring and form good seal structure; therefore, the matching section presses the insulating rubber ring to be tightly attached to the annular wall, so that high adhesion is achieved, a high sealing effect can be provided, and when the lithium secondary battery is placed in the accommodating space, the problem of battery leakage can be solved.

Description

Composite shell structure of button lithium secondary battery

Technical Field

The utility model relates to a lithium ion battery especially relates to a compound shell utensil structure of knot formula lithium secondary battery.

Background

A Lithium-ion battery (Lithium-ion battery) is a rechargeable battery, which mainly works by converting chemical energy into electric energy by means of Lithium ion movement between a positive electrode and a negative electrode, has the advantages of high energy density, no memory effect and the like, and is widely applied to 3C products such as smart phones, tablet computers and the like.

For example, chinese patent No. CN 1178325 "button-shaped storage battery and its manufacturing method" is a button-shaped lithium secondary battery, which includes a case body, a case cover, an insulating gasket, and an electrode assembly, wherein the case body and the case cover are connected through the insulating gasket, the electrode assembly is disposed in the case body and the case cover and has a positive electrode and a negative electrode, and the case body and the case cover are respectively used as a positive electrode and a negative electrode.

In the button lithium secondary battery, the battery case is designed in three pieces, and includes an outer case, an outer case cover, and an insulating gasket, and a station for sleeving the insulating gasket is required during assembly, and the station is required to have matched feeding, inspecting, sleeving, positioning and other strokes, thereby increasing the manufacturing cost.

In addition, the shell also has a manufacturing procedure mode of using in-mold injection, namely a manufacturing method of integrally forming the shell and the insulating sealing gasket, because the outer shell and the insulating sealing gasket have the problem of poor surface fitting degree of a different material in the manufacturing procedure, and the problem that the thickness of the sealing gasket cannot be thinned and the shrinkage proportion exists in the injection molding of the insulating sealing gasket, a through fine space can be formed between the outer shell and the insulating sealing gasket, so that liquid in the battery has an opportunity to seep out from the fine space due to the capillary phenomenon, and the serious liquid leakage problem is easily formed in the assembling process.

SUMMERY OF THE UTILITY MODEL

The main purpose of the present invention is to solve the problem that the conventional case cannot be used to reduce the assembly cost and prevent the battery leakage.

In order to achieve the above object, the utility model provides a compound shell structure of button lithium secondary battery, the utility model discloses the structure includes an interior casing, an insulating rubber ring and one covers the casing outward, wherein this interior casing has a bottom surface, a rampart and an accommodation space, this rampart encircles and connects this bottom surface, this accommodation space is surrounded out by this rampart, and the lateral surface of this rampart has a plurality of shallow slots, and this insulating rubber ring is for imbedding these a plurality of shallow slots and this rampart of cladding with the mode of moulding plastics, and this covers the casing outward and have a closing cap and a crown ring of connecting this closing cap and corresponding this rampart, have a cooperation section on this crown ring, this closing cap of this outer casing shields this accommodation space, and this insulating rubber ring of this crown ring interval seals this accommodation space, in order to utilize this cooperation section suppression this insulating rubber ring and form good seal structure.

In one embodiment, the plurality of shallow grooves are arranged in parallel.

In one embodiment, the plurality of shallow grooves are arranged in a staggered manner.

In one embodiment, the width of the shallow grooves is between 0.01 mm and 2 mm, and the depth of the shallow grooves is between 0.001 mm and 0.1 mm.

In one embodiment, the cap ring further has a pressing section and a sealing section, the sealing section is located at the edge of the cap ring, the pressing section is connected with the matching section and the sealing section, the pressing section is in a flared shape which is enlarged outwards, and the pressing section is bent from the flared shape to a vertical shape so that the sealing section is bent inwards to press the insulating rubber ring.

In one embodiment, the angle between the mating segment and the sealing cover is between 80 degrees and 100 degrees, the angle between the sealing segment and the sealing cover is 90 degrees, and the height dimensions of the mating segment, the pressing segment and the sealing segment must be respectively greater than 0.1 mm.

To sum up, the utility model has the following characteristics:

firstly, the insulating rubber ring is embedded into the shallow grooves and wraps the annular wall, so that the insulating rubber ring and the annular wall have high adhesion, a good joint interface is provided, and the insulating rubber ring is not easy to fall off.

And the outer covering shell is provided with a matching section for pressing the insulating rubber ring, so that a good sealing structure can be formed, and the insulating rubber ring, the ring wall and the matching section are highly laminated, so that a high sealing effect is provided, and the problem of battery leakage can be solved.

Drawings

Fig. 1 is a schematic view of the sectional structure of the inner shell of the present invention.

Fig. 2 is a schematic view of the sectional structure of the insulating rubber ring of the present invention formed on the inner housing.

Fig. 3 is a schematic cross-sectional view of the outer casing before sealing.

Fig. 4 is a schematic view of the sectional structure of the present invention when sealing.

Fig. 5 is the schematic view of the overall cross-sectional structure after the sealing of the present invention.

Wherein, the reference numbers:

inner housing 10

Bottom surface 11

Surrounding wall 12

Shallow groove 121

Accommodating space 13

Outer covering shell 20

Closure cap 21

Cap ring 22

Pressing section 222

Seal section 223

Mating segment 221

Insulating rubber ring 30

Extrusion die 40

Parallel section 41

Active segment 42

Detailed Description

The detailed description and technical contents of the present invention will now be described with reference to the accompanying drawings as follows:

referring to fig. 1, 2 and 3, the present invention provides a composite casing structure of a button lithium secondary battery, comprising an inner casing 10, an outer casing 20 and an insulating rubber ring 30, wherein the inner casing 10 has a bottom surface 11, a ring wall 12 and an accommodating space 13, the ring wall 12 is connected to the bottom surface 11 in a surrounding manner, the accommodating space 13 is surrounded by the ring wall 12, the outer side surface of the ring wall 12 has a plurality of shallow grooves 121, and the insulating rubber ring 30 is embedded into the plurality of shallow grooves 121 in an injection molding manner and covers the ring wall 12 (as shown in fig. 2). The outer casing 20 has a cover 21 and a cap ring 22 connected to the cover 21 and corresponding to the annular wall 12, the cap ring 22 has a matching section 221, the cover 21 of the outer casing 20 covers the accommodating space 13, and the cap ring 22 separates the insulating rubber ring 30 and seals the accommodating space 13, so as to utilize the matching section 221 to press the insulating rubber ring 30 to form a good sealing structure.

Referring to fig. 4 and 5, the manufacturing method of the present invention is to insert the insulating rubber ring 30 into the shallow grooves 121 and cover the annular wall 12 by injection molding; then, the cover 21 of the outer casing 20 covers the accommodating space 13, and the cap ring 22 separates the insulating rubber ring 30 and seals the accommodating space 13, so as to utilize the matching section 221 to press the insulating rubber ring 30 to form a sealing structure. The detailed steps of the manufacturing method are described below.

The inner housing 10 may be formed by machining the outer side surface of the annular wall 12 by cutting micro machining to form the plurality of shallow grooves 121, wherein the width of the plurality of shallow grooves 121 is between 0.01 millimeter (mm) and 2.0 millimeters (mm), and the width is selected in order to make the insulating rubber ring 30 more flexible and airtight. The depth of the shallow grooves 121 is between 0.001 millimeter (mm) and 0.1 millimeter (mm), the depth is selected in consideration of locally adjusting and thickening the thickness of the insulating rubber ring 30, and the arrangement of the shallow grooves 121 can be parallel arrangement or staggered arrangement, so that the thickness of the insulating rubber ring 30 can be changed during injection molding, the external dimension cannot be influenced, and the fitting degree and the air tightness can be improved.

When the insulating rubber ring 30 is injection molded, in order to place the inner housing 10 in an injection molding device, the outer side surface of the annular wall 12 is subjected to rubber coating injection molding in an in-mold injection molding mode, metal and a rubber material are integrally formed, i.e., a composite housing of the inner housing 10 and the insulating rubber ring 30 can be manufactured without glue sheathing assembly, and the shell thickness of the composite housing of the inner housing 10 and the insulating rubber ring 30 can be controlled within 0.3 millimeter (mm), so that compared with the same external dimension, a thinner shell thickness can obtain a better internal space, and the capacity and the product competitiveness of a battery product are improved.

In another embodiment, the cap ring 22 may further have a pressing section 222 and a sealing section 223 besides the matching section 221, the sealing section 223 is located at the edge of the cap ring 22, the pressing section 222 connects the matching section 221 and the sealing section 223, and the pressing section 222 is of an outwardly enlarged bell-mouth type. The manufacturing method further includes a sealing process, i.e. bending the pressing section 222 to bend the sealing section 223 inwards to press the insulating rubber ring 30 (as shown in fig. 5).

The pressing section 222 is mainly used to provide a working surface for inward pressing for sealing. More specifically, when the pressing section 222 is bent (formed) from the flare shape to the vertical shape, the sealing section 223 will be bent inward to press the insulating rubber ring 30 to prevent the outer casing 20 from falling off (as shown in fig. 5). Preferably, the angle between the engaging section 221 and the cover 21 is between 80 degrees and 100 degrees, and the angle between the sealing section 223 and the cover 21 is 90 degrees; and preferably the height dimensions of the fitting section 221, the pressing section 222 and the sealing section 223 must be greater than 0.1 millimeter (mm), respectively.

In the bending part of the pressing section 222, an extrusion die 40 may be used to bend the pressing section 222, the extrusion die 40 has a parallel section 41 and an action section 42, the parallel section 41 is connected to the action section 42, the size of the parallel section 41 is larger than that of the pressing section 222, the size of the action section 42 is smaller than that of the pressing section 222, the action section 42 presses the pressing section 222 to generate mechanical pressure, and the pressing section 222 is bent to allow the sealing section 223 to be bent inward to complete the sealing procedure, so that the riveting speed can be increased and the inner shell 10 is not damaged by the two-section design of the parallel section 41 and the action section 42, and a more uniform external dimension can be obtained.

To sum up, the utility model has the following characteristics:

firstly, the insulating rubber ring is embedded into the shallow grooves and covers the ring wall, and the process of sleeving the rubber ring is not needed, so that the manufacturing cost can be saved.

And secondly, the insulating rubber ring has high fitting property with the annular wall, has a good joint interface and is not easy to fall off.

And thirdly, the shell thickness of the inner shell can be controlled within 0.3 millimeter (mm), and compared with the same external dimension, the thinner shell thickness can obtain a better internal space, thereby improving the capacity and the product competitiveness of the battery product.

Fourthly, the outer casing is provided with a matching section for pressing the insulating rubber ring, a good sealing structure can be formed by pressing the insulating rubber ring through the matching section, and the insulating rubber ring is highly attached to the annular wall and the matching section, so that a high sealing effect is provided, and the problem of battery leakage can be prevented.

Fifthly, the pressing section is bent in a two-section riveting mode, so that the sealing section is bent inwards to finish the sealing process, the sealing air tightness can be effectively achieved, and the size of the shell is kept not to deform or fall off when the shell is thinned.

Naturally, the present invention can be implemented in other various embodiments, and various changes and modifications can be made by those skilled in the art without departing from the spirit and the essence of the present invention, but these changes and modifications should fall within the scope of the present invention defined by the appended claims.

Claims

1. A composite shell structure of button lithium secondary battery is characterized in that it includes:

an inner shell, which is provided with a bottom surface, a ring wall and an accommodating space, wherein the ring wall is connected with the bottom surface in a surrounding way, the ring wall surrounds the accommodating space, and the outer side surface of the ring wall is provided with a plurality of shallow grooves;

the insulating rubber ring is embedded into the shallow grooves in an injection molding mode and covers the annular wall; and

the outer covering shell is provided with a sealing cover and a cap ring which is connected with the sealing cover and corresponds to the ring wall, a matching section is arranged on the cap ring, the sealing cover of the outer covering shell covers the containing space, and the cap ring is arranged at intervals of the insulating rubber ring and seals the containing space so as to utilize the matching section to press the insulating rubber ring to form a sealing structure.

2. The composite case structure of button lithium secondary battery according to claim 1, wherein the plurality of shallow grooves are arranged in parallel.

3. The composite case structure of button lithium secondary battery as claimed in claim 1, wherein the plurality of shallow grooves are arranged in a staggered manner.

4. The composite casing structure of button lithium secondary battery according to claim 1, wherein the width of the plurality of shallow grooves is between 0.01 mm and 2 mm, and the depth of the plurality of shallow grooves is between 0.001 mm and 0.1 mm.

5. The composite casing structure of button-type lithium secondary battery as claimed in claim 1, wherein the cap ring further has a pressing section and a sealing section, the sealing section is located at the edge of the cap ring, the pressing section connects the fitting section and the sealing section, and the pressing section is of outwardly enlarged bell-mouth type, and the pressing section is bent from the bell-mouth type to a vertical type to allow the sealing section to be bent inward against the insulating rubber ring.

6. The composite casing structure of button lithium secondary battery as claimed in claim 5, wherein the angle between the fitting section and the cap cover is between 80-100 degrees, the angle between the cap cover and the cap cover is 90 degrees, and the height dimension of the fitting section, the pressing section and the cap cover must be greater than 0.1 mm respectively.