CN218677505U

CN218677505U - High-safety lithium battery cap

Info

Publication number: CN218677505U
Application number: CN202223104682.XU
Authority: CN
Inventors: 邢诗娜; 郭妍奇
Original assignee: Hengdian Group DMEGC Magnetics Co Ltd
Current assignee: Hengdian Group DMEGC Magnetics Co Ltd
Priority date: 2022-11-21
Filing date: 2022-11-21
Publication date: 2023-03-21
Anticipated expiration: 2032-11-21

Abstract

The utility model discloses a high security lithium cell block belongs to the technical field of lithium cell block, including the sealing washer, the inside of sealing washer is equipped with the step, and the setting of explosion-proof piece is in the top of step, and the top of explosion-proof piece is connected with the electrode cap, and the below of explosion-proof piece is equipped with current shutdown mechanism, is equipped with first protruding circle on the bottom surface of sealing washer. The utility model discloses a space between utmost point group head and the explosion-proof piece has been increased in the setting of first protruding circle, and when short circuit or overcharge test, more gas can be gathered in this space to the pressure that acts on the explosion-proof piece can be bigger, thereby can once only fracture between the solder joint of ensureing explosion-proof piece and current shutdown mechanism, cuts off the electric current immediately, avoids electrolyte to reveal or the battery explosion.

Description

High-safety lithium battery cap

Technical Field

The utility model belongs to the technical field of the lithium cell block, concretely relates to high security lithium cell block.

Background

Currently, lithium ion batteries on the market, such as 18650 cylindrical lithium batteries, basically employ a combined cap including various components such as a current interrupt mechanism (CID). When the cell is abused, especially overcharged, a large amount of gas is generated inside the cell. Because the inside of the battery core is a fully-closed space, the gas can act on the cap cover at the head part of the battery core, namely acts on the welding position of the explosion-proof sheet and the current cut-off mechanism at the cap cover. When the internal air pressure reaches the welding spot pressure limit value between the current cut-off mechanism and the explosion-proof sheet, the current cut-off mechanism is disconnected with the explosion-proof sheet. At the moment, the disconnected current cut-off mechanism is not electrified any more and is not the positive end of the battery, and the whole loop is disconnected, so that the safety of the battery core is ensured.

Traditional cylindrical lithium cell block structure need test in actual production, at overcharge or short circuit test in-process, discovers the condition that can not once only fracture between the solder joint of current cutting mechanism and the explosion-proof piece, leads to the unable immediate cutting off of electric current, has the risk that electrolyte reveals or the battery explodes.

SUMMERY OF THE UTILITY MODEL

To solve the problems set forth in the background art described above. The utility model provides a high security lithium cell block cap has when breaking down, ensures that can disposable fracture between explosion-proof piece and the solder joint of electric current shutdown mechanism, cuts off the electric current immediately, avoids electrolyte to reveal or the characteristics of battery explosion.

In order to achieve the above object, the utility model provides a following technical scheme: the utility model provides a high security lithium cell block, includes the sealing washer, and the inside of sealing washer is equipped with the step, and the setting of explosion-proof piece is in the top of step, and the top of explosion-proof piece is connected with the electrode cap, and the below of explosion-proof piece is equipped with current-cut off mechanism, is equipped with first protruding circle on the bottom surface of sealing washer.

In order to be connected explosion-proof piece and current-cutting mechanism and electrode cap, further, explosion-proof piece includes deformation portion, and the bottom and the current-cutting mechanism welding of deformation portion intermediate position are connected with the welding part on the periphery of deformation portion.

In order to make the connection between the explosion-proof sheet and the electrode cap more stable, further, the welding part is in a U-shaped structure.

In order to facilitate the disconnection between the deformation part and the welding part, further, the upper side and the lower side of the connection part of the deformation part and the welding part are both provided with corresponding arc-shaped grooves.

For insulation between the outer periphery of the current interrupting mechanism and the rupture disk, further, an insulating ring is provided between the outer periphery of the current interrupting mechanism and the rupture disk.

In order to ensure the height difference between the outer periphery of the explosion-proof piece and the current cut-off mechanism, a supporting block is further arranged between the insulating ring and the current cut-off mechanism.

In order to further increase the space between the head of the pole group and the explosion-proof sheet and ensure the pressure acting on the explosion-proof sheet, a second convex ring is further arranged on the step.

In order to ensure that the sealing ring does not deform even at high temperature inside the battery and avoid leakage of electrolyte, the sealing ring is a polyimide component.

Compared with the prior art, the beneficial effects of the utility model are that:

1. the utility model discloses a space between the head of utmost point group and the explosion-proof piece has been increased through the setting of first protruding circle, and during short circuit or overcharge test, more gas can be gathered to this space to the pressure that acts on the explosion-proof piece can be bigger, thereby can once only fracture between the solder joint of ensureing explosion-proof piece and electric current shutdown mechanism, cuts off electric current immediately, avoids electrolyte to reveal or the battery explosion;

2. the welding part of the utility model is in a U-shaped structure, so that the connection between the explosion-proof sheet and the electrode cap is more stable; the second convex ring is arranged on the step of the utility model, so that the space between the head of the pole group and the explosion-proof sheet is further increased, and the pressure acting on the explosion-proof sheet is ensured;

3. the utility model discloses the sealing washer is the polyimide component, and polyimide's melting point can reach 400 degrees centigrade, ensures when the inside high temperature of battery, and deformation can not take place yet to the sealing washer, avoids electrolyte to reveal.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic view of the present invention;

FIG. 2 is a schematic view of a partial structure of the explosion-proof sheet of the present invention;

fig. 3 is a schematic view of a partial structure of the sealing ring of the present invention;

in the figure: 1. an electrode cap; 2. a support block; 3. an insulating ring; 4. an explosion-proof sheet; 41. a deformation section; 42. a connecting portion; 43. welding the part; 44. an arc-shaped slot; 5. a current cutoff mechanism; 6. a seal ring; 61. a first convex ring; 62. and a second convex ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Example 1

Referring to fig. 1-3, the present invention provides the following technical solutions: the utility model provides a high security lithium cell block, includes sealing washer 6, and the inside of sealing washer 6 is equipped with the step, and explosion-proof piece 4 sets up in the top of step, and the top of explosion-proof piece 4 is connected with electrode cap 1, and the below of explosion-proof piece 4 is equipped with current-cut off mechanism 5, is equipped with first protruding circle 61 on the bottom surface of sealing washer 6.

Through adopting above-mentioned technical scheme, through the setting of first protruding circle 61, increased the space between utmost point group head and explosion-proof piece 4, when short circuit or overcharge test, more gas can be gathered in this space to the pressure that is used in on explosion-proof piece 4 can be bigger, thereby can once only fracture between the solder joint of ensureing explosion-proof piece 4 and current cutting mechanism, cuts off the electric current immediately, avoids electrolyte to reveal or the battery explosion.

Specifically, the explosion-proof sheet 4 includes a deformation portion 41, a bottom portion of an intermediate position of the deformation portion 41 is welded to the current cut-off mechanism 5, and a welding portion 43 is connected to an outer periphery of the deformation portion 41.

Through adopting above-mentioned technical scheme for be connected explosion-proof piece 4 with current-cut off mechanism 5 and electrode cap 1.

Specifically, an insulating ring 3 is provided between the outer periphery of the current interrupting mechanism 5 and the rupture disk 4.

By adopting the above technical solution, the insulating device is used for insulating between the outer periphery of the current cut-off mechanism 5 and the explosion-proof piece 4.

Example 2

The present embodiment is different from embodiment 1 in that: specifically, the welding portion 43 has a U-shaped structure.

Through adopting above-mentioned technical scheme, make be connected more stable between explosion-proof piece 4 and the electrode cap 1.

Example 3

The present embodiment is different from embodiment 1 in that: specifically, the upper and lower sides of the joint of the deformation portion 41 and the welding portion 43 are provided with corresponding arc-shaped grooves 44.

By adopting the above technical scheme, the deformation portion 41 and the welding portion 43 can be conveniently disconnected.

Example 4

The present embodiment is different from embodiment 1 in that: specifically, a supporting block 2 is arranged between the insulating ring 3 and the current cut-off mechanism 5.

By adopting the technical scheme, the height difference between the outer periphery of the explosion-proof sheet 4 and the current cut-off mechanism 5 is ensured.

Example 5

The present embodiment is different from embodiment 1 in that: specifically, the step is provided with a second convex ring 62.

By adopting the technical scheme, the space between the head of the pole group and the explosion-proof piece 4 is further increased, and the pressure acting on the explosion-proof piece 4 is ensured.

Example 6

The present embodiment is different from embodiment 1 in that: specifically, the seal ring 6 is a polyimide member.

By adopting the technical scheme, the melting point of the polyimide can reach 400 ℃, so that the sealing ring 6 can not deform when the battery is at high temperature, and the electrolyte leakage is avoided.

To sum up, the utility model increases the space between the head of the electrode group and the explosion-proof piece 4 through the arrangement of the first convex ring 61, and more gas can be accumulated in the space during short circuit or overcharge test, so that the pressure acting on the explosion-proof piece 4 can be larger, thereby ensuring that the explosion-proof piece 4 and the welding spot of the current cutting mechanism can be broken at one time, cutting off the current immediately, and avoiding electrolyte leakage or battery explosion; the welding part 43 of the utility model is in a U-shaped structure, so that the connection between the explosion-proof sheet 4 and the electrode cap 1 is more stable; the second convex ring 62 is arranged on the step of the utility model, so that the space between the head of the pole group and the explosion-proof sheet 4 is further increased, and the pressure acting on the explosion-proof sheet 4 is ensured; the utility model discloses sealing washer 6 is the polyimide component, and polyimide's melting point can reach 400 degrees centigrade, ensures when the inside high temperature of battery, and sealing washer 6 also can not take place deformation, avoids electrolyte to reveal.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing embodiments, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a high security lithium cell block, includes the sealing washer, its characterized in that: the inside of sealing washer is equipped with the step, and the setting of explosion-proof piece is in the top of step, and the top of explosion-proof piece is connected with the electrode cap, and the below of explosion-proof piece is equipped with current-cutting mechanism, is equipped with first protruding circle on the bottom surface of sealing washer.

2. The high-safety lithium battery cap as claimed in claim 1, wherein: the explosion-proof piece includes deformation portion, and the bottom and the current cutting mechanism welding of deformation portion intermediate position are connected with the weld part on the outer periphery of deformation portion.

3. The high-safety lithium battery cap as claimed in claim 2, wherein: the welding part is of a U-shaped structure.

4. The high-safety lithium battery cap as claimed in claim 2, wherein: the upper side and the lower side of the joint of the deformation part and the welding part are both provided with corresponding arc-shaped grooves.

5. The high-safety lithium battery cap as claimed in claim 1, wherein: an insulating ring is arranged between the outer periphery of the current cutting mechanism and the explosion-proof sheet.

6. The high-safety lithium battery cap as claimed in claim 5, wherein: and a supporting block is arranged between the insulating ring and the current cutting mechanism.

7. The high-safety lithium battery cap as claimed in claim 1, wherein: and a second convex ring is arranged on the step.

8. The high-safety lithium battery cap as claimed in claim 1, wherein: the seal ring is a polyimide component.