CN216354494U

CN216354494U - Secondary battery

Info

Publication number: CN216354494U
Application number: CN202122405884.7U
Authority: CN
Inventors: 郭勇凯; 徐卫东
Original assignee: Xiamen Haichen New Energy Technology Co Ltd
Current assignee: Xiamen Hithium Energy Storage Technology Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2022-04-19
Anticipated expiration: 2031-09-30

Abstract

The application provides a secondary battery, which comprises a shell, a naked electric core and a bottom supporting plate; wherein, an insulating film is coated outside the naked electric core; the bottom supporting plate is fixedly connected to the bottom of the insulating film; the bottom supporting plate is a sheet-shaped body which is not provided with an electrolyte penetration hole; the bare cell, the insulating film and the bottom support plate are all accommodated in the shell. The secondary battery that this application embodiment provided because do not set up the electrolyte through hole on the bottom plate, electrolyte can not enter into the bottom of casing from this almost, has avoided the casing to take place the problem of corroding. This is because, once the electrolyte enters the inside of the case through the bottom support plate, if the case is an aluminum case, lithium ions and the aluminum case act to form a lithium aluminum alloy, and further form a potential difference with the pole piece. When the external short circuit of the battery cell occurs, the corrosion of the bottom of the shell can be caused. The secondary battery provided by the embodiment of the application solves the technical problem.

Description

Secondary battery

Technical Field

The application relates to the technical field of energy storage, in particular to a secondary battery.

Background

Secondary batteries typically include important components such as a housing and a bare cell, which is typically a wound or laminated structure having a separator film formed between a cathode pole piece and an anode pole piece. Naked electric core passes through the support of collet plate, holds in the casing.

In the existing battery manufacturing process, electrolyte is injected into a shell and is used for soaking a pole piece. The two electrolytes enter the bottom of the shell through the bottom supporting plate, and the shell is usually an aluminum shell, so that when the secondary battery is subjected to external short circuit, the bottom of the aluminum shell can be corroded.

SUMMERY OF THE UTILITY MODEL

The application provides a secondary battery to solve the problem that a shell is easy to corrode in the prior art.

The embodiment of the application provides a secondary battery, which comprises a shell, a naked electric core and a bottom supporting plate;

wherein, an insulating film is coated outside the naked electric core;

the bottom supporting plate is fixedly connected to the bottom of the insulating film; the bottom supporting plate is a sheet-shaped body which is not provided with an electrolyte penetration hole;

the bare cell, the insulating film and the bottom support plate are all accommodated in the shell.

The secondary battery that this application embodiment provided because do not set up the electrolyte through hole on the bottom plate, electrolyte can not enter into the bottom of casing from this almost, has avoided the casing to take place the problem of corroding. This is because, once the electrolyte enters the inside of the case through the bottom support plate, if the case is an aluminum case, lithium ions and the aluminum case act to form a lithium aluminum alloy, and further form a potential difference with the pole piece. When the external short circuit of the battery cell occurs, the corrosion of the bottom of the shell can be caused. The secondary battery provided by the embodiment of the application solves the technical problem.

In one possible embodiment, the bottom of the insulating film is not provided with an electrolyte permeation hole.

In one possible embodiment, the insulating film is integrally formed with the bottom bracket.

In a possible embodiment, the bottom support plate and the bare cell satisfy:

L1＝L3±50mm；

W1＝W3±50mm；

H1＝0-10mm；

wherein L1 is the length of the bottom pallet, W1 is the width of the bottom pallet, H1 is the thickness of the bottom pallet;

l3 is the length of naked electric core, W3 is the width of naked electric core.

In one possible embodiment, the insulating film and the bare cell satisfy:

L2＝(2*H3+W3)+t1；

W2＝W3+H3+t2；

H2＝0-10mm；

wherein L2 is the length of the insulating film, W2 is the width of the insulating film, and H2 is the thickness of the insulating film;

h3 is the height of the naked battery cell;

t1≤20mm；

t2≤H3。

in a possible embodiment, 1-2 first positioning holes are provided in the bottom bracket plate.

In one possible embodiment, the insulating film is provided with a second positioning hole matching the first positioning hole.

In one possible embodiment, the housing is an aluminum shell.

In one possible embodiment, the bottom plate is rectangular sheet-like.

In one possible embodiment, the secondary battery further includes a top cover sheet that closes the opening of the case to enclose the bare cell within the case.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

Fig. 1 is a schematic structural view of a secondary battery provided in an embodiment of the present application;

fig. 2 is an exploded view of an insulating film, a bottom bracket plate, and a case in a secondary battery according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a bottom plate in a secondary battery provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of a bare cell in a secondary battery provided in an embodiment of the present application.

Reference numerals:

100-a secondary battery; 1-a shell; 2-top cover sheet; 21-pole column; 3-an insulating film; 31-a second positioning hole; 4-bottom pallet; 41-a first positioning hole; 5-naked electric core.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

Detailed Description

For better understanding of the technical solutions of the present application, the following detailed descriptions of the embodiments of the present application are provided with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of a secondary battery provided in an embodiment of the present application; fig. 2 is an exploded view of an insulating film, a bottom bracket plate, and a case in a secondary battery according to an embodiment of the present invention; fig. 3 is a schematic structural diagram of a bottom plate in a secondary battery provided in an embodiment of the present application; fig. 4 is a schematic structural diagram of a bare cell in a secondary battery provided in an embodiment of the present application.

As shown in fig. 1 to 4, the embodiment of the present application provides a secondary battery 100, including casing 1, naked electric core 5 and bottom plate 4, wherein, casing 1 can be the shape of cuboid, and the inside formation of this casing 1 holds the chamber for hold naked electric core 5 and electrolyte, the one end opening of casing 1, make this opening of naked electric core 5 accessible place in the chamber that holds of casing 1, and hold the intracavity and can be provided with a plurality of naked electric cores 5, the range upon range of setting of a plurality of naked electric cores 5. The housing 1 may include a metal material, such as aluminum or aluminum alloy, and may also include an insulating material, such as plastic.

Be provided with utmost point post 21 on the top plate 2, be positive post 21 and negative pole post 21 respectively, top plate 2 is fixed in casing 1's opening to seal naked electric core 5 and electrolyte in the chamber that holds of casing 1, be connected through adapting unit electricity between two utmost point posts 21 and the utmost point ear that corresponds, the top plate is provided with explosion-proof mouthful, explosion-proof valve sets up at explosion-proof mouthful, when electric core emergence thermal runaway, its inside gas can be discharged through explosion-proof valve, in order to improve the security of electric core.

Wherein, the naked electric core 5 is coated with an insulating film 3, and the bottom supporting plate 4 is fixedly connected with the bottom of the insulating film 3; the bottom supporting plate 4 is a sheet-shaped body which is not provided with an electrolyte penetration hole, and the naked electric core 5, the insulating film 3 and the bottom supporting plate 4 are all accommodated in the shell 1.

In the secondary battery 100 provided in the embodiment of the present application, since the bottom support plate 4 is not provided with the electrolyte passing hole, the electrolyte hardly enters the bottom of the case 1, and the problem of corrosion of the case 1 is avoided. This is because, once the electrolyte enters the inside of the case 1 through the bottom bracket 4, if the case 1 is an aluminum case, the lithium ions and the aluminum case act to form a lithium aluminum alloy, and further form a potential difference with the pole piece. When the external short circuit occurs in the battery cell, the corrosion of the bottom of the shell 1 can be caused. The secondary battery 100 provided by the embodiment of the present application solves the above-described technical problems.

Because insulating film 3 cladding is in the outside of naked electric core 5, the bottom of insulating film 3 has not seted up the electrolyte and has passed through the hole to further prevent that electrolyte from entering into casing 1 bottom.

Preferably, the insulating film 3 is integrally formed with the bottom plate 4. The bottom plate 4 may be made of PP, PET or PI, and both the bottom plate 4 and the insulating film 3 may be formed by thermal molding.

Further, bottom plate 4 satisfies with naked electric core 5: l1 ═ L3 ± 50 mm; w1 ═ W3 ± 50 mm; h1-0-10 mm;

wherein L1 is the length of the bottom plate 4, W1 is the width of the bottom plate 4, and H1 is the thickness of the bottom plate 4. L3 is the length of naked electric core 5, and W3 is the width of naked electric core 5.

After bottom plate 4 and naked electric core 5 satisfied above-mentioned size, bottom plate 4 can reach the effect of bearing naked electric core 5. And the bottom plate 4 has a moderate thickness and has sufficient strength without increasing the weight of the secondary battery 100.

Further, satisfy between insulating film 3 and the naked electric core 5: l2 ═ (2 × H3+ W3) + t 1; w2 ═ W3+ H3+ t 2; h2-0-10 mm; wherein L2 is the length of the insulating film 3, W2 is the width of the insulating film 3, and H2 is the thickness of the insulating film 3; h3 is the height of the bare cell 5; t1 is less than or equal to 20 mm; t2 is less than or equal to H3.

In one possible embodiment, 1-2 first positioning holes 41 are provided in the bottom bracket plate 4. When the bottom plate 4 and the insulating film 3 are subjected to the thermoplastic molding, the bottom plate 4 can be positioned through the first positioning hole 41. After the thermoplastic, the first positioning hole 41 may be closed to prevent the electrolyte from penetrating. The first positioning hole 41 may not be closed, and the amount of the electrolyte that permeates therethrough is extremely small, which still does not affect the performance of the secondary battery 100.

In one possible embodiment, the insulating film 3 is provided with a second positioning hole 31 matching the first positioning hole 41 described above. When the bottom plate 4 and the insulating film 3 are subjected to the thermoplastic molding, the insulating film 3 can be positioned through the second positioning hole 31.

In one possible embodiment, the housing 1 is an aluminum shell.

Specifically, the bottom plate 4 is rectangular plate-shaped.

In addition, secondary battery 100 still includes top cover plate 2, and top cover plate 2 seals the opening at casing 1 to seal naked electric core 5 in casing 1.

It is noted that a portion of this patent application contains material which is subject to copyright protection. The copyright owner reserves the copyright rights whatsoever, except for making copies of the patent files or recorded patent document contents of the patent office.

Claims

1. A secondary battery is characterized by comprising a shell, a naked electric core and a bottom supporting plate;

wherein, an insulating film is coated outside the naked electric core;

2. The secondary battery according to claim 1, wherein the insulating film has no electrolyte permeation hole opened at a bottom thereof.

3. The secondary battery according to claim 2, wherein the insulating film is integrally formed with the bottom tray.

4. The secondary battery of any of claims 1-3, wherein the bottom pallet and the bare cell satisfy:

L1＝L3±50mm；

W1＝W3±50mm；

H1＝0-10mm；

5. The secondary battery of claim 4, wherein the insulating film and the bare cell satisfy:

L2＝(2*H3+W3)+t1；

W2＝W3+H3+t2；

H2＝0-10mm；

h3 is the height of the naked battery cell;

t1≤20mm；

t2≤H3。

6. the secondary battery according to claim 5, wherein 1-2 first positioning holes are provided on the bottom plate.

7. The secondary battery according to claim 6, wherein a second positioning hole matching the first positioning hole is provided on the insulating film.

8. The secondary battery according to any one of claims 1 to 3, wherein the case is an aluminum case.

9. The secondary battery according to any one of claims 1 to 3, wherein the bottom tray has a rectangular plate shape.

10. The secondary battery of any of claims 1-3, further comprising a top cover sheet closing the opening of the housing to enclose the bare cell within the housing.