Cylindrical lithium ion battery sealing structure

Abstract

The utility model discloses a cylindrical lithium ion battery sealing structure and belongs to the field of batteries. The battery comprises a steel cylindrical shell and a cylindrical battery cell contained in an inner cavity of the shell, the lower end of the shell is open, a current collecting disc and a bottom cover are sequentially arranged in the inner cavity of the open end of the shell from top to bottom, the outer edge of the current collecting disc is turned downwards to form a cylindrical installation connecting part, and the outer wall of the installation connecting part is in interference fit with the wall of the inner cavity of the shell. The top face of the bottom cover abuts against the lower end face of the installation connecting part. The bottom cover and the lower end of the shell are welded and fixed. The bottom cover is provided with an annular groove with a downward opening to form a blasting line, the center face of the bottom cover can protrude outwards when the bottom cover is extruded by internal expansion of the battery, the center face of the bottom cover is torn along the blasting line for explosion venting when the blasting value is reached, and a stamping type reinforcing rib is arranged between the blasting line and the outer edge line of the bottom cover, so that the sealing structure is simplified; the explosion line is arranged on the bottom cover, so that the problem of explosion venting when the internal expansion pressure value of the battery is too large is solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to battery technical field, especially related to a cylindrical lithium ion battery negative electrode seal structure. BACKGROUND

[0002] Cylindrical battery includes cylindrical shell and the cylindrical battery cell that is contained in the shell inner chamber. Cylindrical shell one end opening, cylindrical battery cell is placed from the opening end. The shell of traditional cylindrical lithium ion battery is tensile shell, and the shell bottom is closed, and the top end is opened, and the opening end cover is sealed. Usually battery top is positive end, and is provided with more accessory mechanism. Such battery seal structure is relatively complex, and it is not easy to release pressure after battery overheating expansion, and it is easy to cause the serious consequence of fire explosion, and battery safety is limited. SUMMARY

[0003] The utility model aims at solving the problems of the complex seal structure of the prior art cylindrical lithium ion battery and the difficulty in pressure release, and provides a cylindrical lithium ion battery seal structure with simple structure and explosion release.

[0004] To this end, the utility model adopts the following technical scheme: a cylindrical lithium ion battery seal structure, the battery includes the shell of steel cylindrical and the cylindrical battery cell that is contained in the shell inner chamber, the shell lower end opening, and it is characterized in that: the opening end inner chamber of the shell is sequentially provided with the collecting plate and the bottom cover from top to bottom, the outer edge of the collecting plate is downward flanged to form the cylindrical mounting connecting part, the mounting connecting part outer wall is in interference fit with the shell inner chamber wall, the bottom cover top surface is in close contact with the mounting connecting part lower end face, and the bottom cover and the shell lower end are welded and fixed;The bottom cover is provided with the circular annular groove with the opening downward to form the burst line, and the bottom cover center surface can protrude outward when the bottom cover is extruded by the internal expansion of the battery, and the bottom cover center surface is torn along the burst line when the burst value is reached, and the burst line is provided with the stamping type reinforcing rib between the bottom cover outer edge line.

[0005] As a supplement and improvement of the above technical scheme, the utility model further includes the following technical features.

[0006] The vertical cross section of the circular annular groove is inverted V-shaped, and the explosion release reliability is increased.

[0007] The bottom surface of the bottom cover is flush with the lower end surface of the shell.

[0008] The reinforcing rib protrudes upward, and the reinforcing rib is surrounded in the inner chamber of the mounting connecting part.

[0009] The number of reinforcing ribs is multiple, and the reinforcing ribs are distributed in the circumferential direction along the outer periphery of the burst line.

[0010] Each reinforcing rib includes two arc-shaped rib portions surrounding the burst line, and the two arc-shaped rib portions are radially staggered and connected by a connecting portion.

[0011] The utility model discloses can reach following beneficial effect: through setting the shell open end at the bottom side negative pole end, can simplify the seal structure, set the blasting line on the bottom cover can tear the bottom cover along the blasting line and release the explosion when the inside expansion pressure value of battery is too big, avoid battery explosion, improve battery security. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is the front view direction partial section view of the utility model cylindrical lithium ion battery seal structure.

[0013] Figure 2 It is the bottom view of the utility model cylindrical lithium ion battery seal structure.

[0014] Figure 3 It is Figure 1 The partial close-up of a is shown. DETAILED DESCRIPTION

[0015] The specific embodiments of the utility model are described in detail below in combination with the drawings, and the described embodiments are only the description and explanation of the invention, and do not constitute the only limitation of the invention.

[0016] As Figures 1 to 3 The utility model discloses a cylindrical lithium ion battery seal structure, the battery includes the shell 1 of steel cylinder and the cylindrical electric core of containing in the cavity of shell. The lower end of shell 1 is open, and the open end cavity of shell is sequentially provided with the bottom cover 3 and the current collection disc 2 from top to bottom. The outer edge of current collection disc 2 is downwardly turned over to form the cylindrical mounting connecting part 21, and the outer wall of mounting connecting part 21 is in interference fit with the cavity wall of shell 1. The top surface of bottom cover 3 is close to the lower end surface of mounting connecting part 21, and the bottom surface of bottom cover and the lower end surface of shell are flush, and the bottom cover and the lower end of shell are fixed by laser end face welding. The bottom cover is provided with the circular annular groove 32 with downward opening to form the blasting line, and the vertical cross section of circular annular groove 32 is inverted V-shaped, and three stamping type reinforcing ribs 31 are arranged between the blasting line and the outer edge line of bottom cover, and the three reinforcing ribs are distributed along the circumference of blasting line, and the reinforcing rib is upwardly convex, and the reinforcing rib is surrounded in the cavity of mounting connecting part. Each reinforcing rib includes two arc-shaped rib parts around the blasting line, and the two arc-shaped rib parts are staggered in the radial direction to form the inner arc-shaped rib part 313 and the outer arc-shaped rib part 311, and the two arc-shaped rib parts are connected by the connecting part 312.

Claims

1. A cylindrical lithium ion battery sealing structure, the battery comprising a steel cylindrical shell and a cylindrical cell accommodated in the inner cavity of the shell, the lower end of the shell being open, characterized in that: The opening end inner cavity of the shell is sequentially provided with a collecting plate and a bottom cover from top to bottom, the outer edge of the collecting plate is downwardly turned to form a cylindrical mounting connecting part, the outer wall of the mounting connecting part is in interference fit with the inner cavity wall of the shell, the top surface of the bottom cover is in close contact with the lower end surface of the mounting connecting part, and the bottom surface of the bottom cover and the lower end surface of the shell are fixed by laser end face welding; the bottom cover is provided with a circular annular groove with an opening downward to form a circular blasting line, and a stamping type reinforcing rib is arranged between the blasting line and the outer edge line of the bottom cover.

2. The cylindrical lithium-ion battery seal structure of claim 1, wherein: The vertical cross section of the circular annular groove is in inverted V shape.

3. The cylindrical lithium-ion battery seal structure of claim 1, wherein: The bottom surface of the bottom cover is flush with the lower end surface of the shell.

4. The cylindrical lithium-ion battery seal structure of claim 1, wherein: The reinforcing rib is upwardly convex, and the reinforcing rib is surrounded in the inner cavity of the mounting connecting part.

5. The cylindrical lithium-ion battery seal structure of claim 1, wherein: The number of the reinforcing ribs is multiple, and the reinforcing ribs are distributed in the circumferential direction along the outer periphery of the blasting line.

6. The cylindrical lithium-ion battery seal structure of claim 5, wherein: Each reinforcing rib comprises two circular arc rib parts surrounding the blasting line, and the two circular arc rib parts are radially staggered and connected by a connecting part.

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