CN209912903U - Cylindrical lithium ion battery cap capable of automatically exhausting - Google Patents

Abstract

The utility model provides a cylindrical lithium ion battery cap capable of automatically exhausting, when the gas pressure generated in the battery cell reaches the threshold value set by the spring 5, the gas passes through the through hole at the bottom edge of the conducting strip 7, pushes the sealing strip 6 and the first sealing ring 8 to move upwards, so that the first sealing ring 8 and the side wall of the conducting strip 7 have a gap, the gas overflows upwards, and diffuses outwards through the through hole of the top cap 4, thereby achieving the purpose of reducing the gas in the battery cell; after the electric core exhausts, when the internal gas pressure is smaller than the threshold value of the spring 5, the spring 5 pushes the sealing sheet 6 and the first sealing ring 8 to move downwards until the first sealing ring 8 is in close contact with the side wall of the conducting sheet 7 again to form a sealing structure, and autonomous exhaust is completed.

Description

Cylindrical lithium ion battery cap capable of automatically exhausting

Technical Field

The utility model relates to the lithium ion battery field especially relates to a but self-bleeding cylinder lithium ion battery block.

Background

The increase in energy density has been one of the directions in which practitioners of lithium ion batteries are constantly striving. The high nickel anode material and the silicon cathode material are the necessary way for improving the energy density of the lithium ion battery. Because of the problems of gas generation of the high-nickel anode material and the silicon cathode material, volume change of the silicon cathode and the like, the cylindrical battery cell becomes a battery cell form which realizes batch production of the high-nickel anode material and the silicon cathode material. However, the hard shell structure of the cylindrical battery can only prevent the volume change caused by the gas generation problem of the material, but cannot solve the gas generation problem of the material and eliminate a series of negative effects on the performance of the battery cell caused by the gas generation problem, and the battery cell is very easy to fail due to the overturning of the cap CID caused by the gas generation problem. In order to reduce the influence caused by gas generation of the material, a common measure in the industry at present is to strictly control the environmental humidity in the manufacturing process of the battery cell, so as to reduce the moisture content introduced into the battery cell to the minimum, but inevitably introduce a trace amount of moisture, so as to become a gas generation source in the subsequent battery cell. Meanwhile, most of gas can be discharged from the aluminum shell battery cell in an opening formation mode, and the air bag which can be cut off after formation is reserved during packaging of the soft package battery cell, so that the problem of gas generation in the battery cell can be relieved to a certain extent, and the negative influence caused by the gas generation problem is reduced. Therefore, the gas generated by the cylindrical battery cell which cannot be discharged becomes a big pain point which restricts the rapid popularization and application of the high-nickel anode material and the silicon cathode material in the cylindrical battery cell.

Disclosure of Invention

An object of the utility model is to the above-mentioned problem, but provide a cylinder lithium ion battery block of self-bleeding, can be with the gaseous automatic discharge of the inside production of electric core to reduce the inside gaseous negative effects to electric core performance production of electric core.

The technical scheme of the utility model is that:

a cylindrical lithium ion battery cap capable of automatically exhausting comprises a top cover positioned on the uppermost layer of the center;

the top cover is provided with a vent hole;

a conducting strip with an inverted trapezoidal section and an opening at the upper end is arranged below the top cover, the upper edge of the conducting strip is connected with the edge of the top cover through a welding spot, and the edge of the conducting strip covers the top cover to form a cavity;

the bottom edge of the conducting strip is arranged to be in a step structure from the center to the edge, and the central area of the bottom edge of the conducting strip is allowed to generate certain displacement upwards;

the conductive sheet is provided with a vent hole;

a sealing sheet is arranged in a cavity formed by the top cover and the conducting sheet, and a first sealing ring is wrapped around the sealing sheet and is in close contact with the side wall of the conducting sheet;

the center of the bottom edge of the conducting strip protrudes upwards and is connected with the lower surface of the sealing strip through a welding spot;

the upper surface of the sealing piece is connected with the lower surface of the top cover through a spring, and the spring applies downward force to the sealing piece to prevent the sealing piece from moving upwards;

a second sealing ring is arranged outside the conducting plate and is tightly combined with the outer surface of the side wall of the conducting plate;

an outer wrapping sheet is arranged outside the second sealing ring, the cross section of the outer wrapping sheet is in an inverted L shape, and the edge of the horizontal part of the outer wrapping sheet is tightly contacted with the second sealing ring;

and a third sealing ring is arranged on the inner surface of the vertical part of the outer wrapping sheet, and the inner surface of the vertical part of the outer wrapping sheet is in close contact with the third sealing ring.

The utility model provides a block has following beneficial technological effect:

(1) when the gas pressure generated in the battery cell reaches a threshold value set by the spring, the gas passes through the through hole at the bottom edge of the conducting plate, pushes the sealing plate and the first sealing ring to move upwards, so that a gap is formed between the first sealing ring and the side wall of the conducting plate, the gas overflows upwards, and diffuses to the external environment through the through hole of the top cover, thereby achieving the purpose of reducing the gas in the battery cell; after the battery cell is exhausted, when the internal gas pressure is smaller than the spring threshold value, the spring pushes the sealing sheet and the first sealing ring to move downwards until the first sealing ring is in close contact with the side wall of the conducting sheet again to form a sealing structure;

(2) when the battery cell fails and generates a large amount of gas, the gas pushes the sealing plate and the first sealing ring to move upwards, and when the gas amount is large enough, the sealing plate and the first sealing ring move upwards enough to enable the sealing plate to be separated from the welding of the bottom edge of the conducting plate, so that the connection between the battery cell and an external circuit is disconnected, the failure is prevented from further occurring, and a protection effect is achieved;

(3) the utility model provides a block, it is insulating to have the second sealing washer between the top cap as the positive terminal and the piece of outsourcing, and be used for sealing and have the third sealing washer between sealed piece of outsourcing and the box hat insulating, the piece of outsourcing just so with as the top cap of positive terminal insulating, and as the box hat of negative pole end also insulating, even this kind of design block end center top cap has other foreign matters to switch on and also can not cause the outside short circuit of electric core with the piece of outsourcing to play the effect of preventing outside short circuit.

Drawings

FIG. 1 is a cross-sectional view of the present invention;

fig. 2 is a cross-sectional view of the assembled cylindrical lithium ion battery cap and steel shell of the present invention;

in the figure, 0 is the steel casing, 1 is the outsourcing piece, 2 is the third sealing washer, 3 is the second sealing washer, 4 is the top cap, 5 is the spring, 6 is the gasket, 7 is the conducting strip, 8 is first sealing washer.

Detailed Description

As shown in fig. 1 and 2, the cylindrical lithium ion battery cap of the present invention comprises a top cap 4 located at the center, wherein the top cap 4 is provided with an air vent; the section of the conducting strip 7 is in an inverted trapezoid shape, the upper edge of the conducting strip is connected with the top cover 4 through a welding spot, the edge of the conducting strip covers the top cover 4, and a cavity is formed between the conducting strip and the top cover; the bottom edge of the conducting plate 7 is provided with a vent hole, the bottom edge of the conducting plate 7 is provided with a step structure from the center to the edge, the center step is highest, the center position is allowed to have certain displacement in the up-down direction, and the highest position is connected with the lower surface of the sealing plate 6 through welding; a first sealing ring 8 is wrapped around the sealing sheet 6, and the first sealing ring 8 is in close contact with the side wall of the conducting sheet 7; a spring 5 is arranged on the upper surface of the sealing sheet 6, and the other end of the spring 5 is connected with the lower surface of the top cover 4; the spring forms downward force to the sealing sheet 6, and the downward force is balanced with upward force formed by the side surface of the conducting sheet 7 to the sealing sheet 6; the second sealing ring 3 is coated on the outer ring of the conducting strip 7, and the section of the outer coating sheet 1 is coated on the outer ring of the second sealing ring 3 in an inverted L shape; the inner side and the outer side of the second sealing ring 3 are respectively in close contact with the side surface of the conducting strip 7 and the inner side of the outer wrapping sheet 1; and a third sealing ring 2 is arranged on the inner side of the vertical part of the outer wrapping sheet 1, and the third sealing ring 2 is in close contact with the inner side of the outer wrapping sheet 1. When the cap is assembled on the steel shell 0, the sealing sheet 6 and the first sealing ring 8 form an airtight structure with the interior of the steel shell 0.

When the gas pressure generated in the battery cell reaches the threshold value set by the spring 5, the gas pushes the sealing sheet 6 and the first sealing ring 8 to move upwards through the through hole at the bottom edge of the conducting sheet 7, so that a gap is formed between the first sealing ring 8 and the side wall of the conducting sheet 7, the gas overflows upwards, and diffuses towards the external environment through the through hole of the top cover 4, and the purpose of reducing the gas in the battery cell is achieved; after the electric core exhausts, when the internal gas pressure is smaller than the threshold value of the spring 5, the spring 5 pushes the sealing sheet 6 and the first sealing ring 8 to move downwards until the first sealing ring 8 is in close contact with the side wall of the conducting sheet 7 again to form a sealing structure, and autonomous exhaust is completed.

When the battery cell fails and generates a large amount of gas, the gas pushes the sealing sheet 6 and the first sealing ring 8 to move upwards, and when the gas amount is large enough, the sealing sheet 6 and the first sealing ring 8 move upwards enough, so that the sealing sheet 6 and the bottom edge of the conducting sheet 7 can be welded and separated, the connection between the battery cell and an external circuit is broken, the failure is prevented from further occurring, and a protection effect is achieved.

There is the second sealing washer 3 to insulate between top cap 4 and the outer cover piece 1 as positive terminal, and it is insulating to have the third sealing washer 2 between outer cover piece 1 and the steel casing 0 for sealing sealed, and outer cover piece 1 is just insulating with top cap 4 as positive terminal like this, and also insulating as steel casing 0 of negative terminal, even this kind of design has other foreign matters to switch on cap end center top cap 4 and outer cover piece 1 and also can not cause the outside short circuit of electric core, thereby play the effect of preventing outside short circuit.

Claims (1)

1. The cylindrical lithium ion battery cap capable of automatically exhausting is characterized by comprising a top cover positioned on the uppermost layer of the center,

the top cover is provided with a vent hole,

a conductive sheet with an inverted trapezoidal section and an opening at the upper end is arranged below the top cover, the upper edge of the conductive sheet is connected with the edge of the top cover through a welding spot, and the edge of the conductive sheet covers the top cover to form a cavity,

the bottom edge of the conducting strip is arranged in a step structure from the center to the edge position, the central area of the bottom edge of the conducting strip is allowed to generate a certain displacement upwards,

the bottom edge of the conducting strip is provided with a vent hole,

a sealing sheet is arranged in a cavity formed by the top cover and the conducting sheet, a first sealing ring is wrapped around the sealing sheet and is in close contact with the side wall of the conducting sheet,

the center of the bottom edge of the conducting strip is raised upwards and is connected with the lower surface of the sealing strip through a welding spot,

the upper surface of the sealing sheet is connected with the lower surface of the top cover through a spring, the spring applies downward force to the sealing sheet to prevent the sealing sheet from moving upwards,

a second sealing ring is arranged outside the conducting strip and is tightly combined with the outer surface of the side wall of the conducting strip,

an outer wrapping sheet is arranged outside the second sealing ring, the cross section of the outer wrapping sheet is in an inverted L shape, the edge of the horizontal part of the outer wrapping sheet is tightly contacted with the second sealing ring,

and a third sealing ring is arranged on the inner surface of the vertical part of the outer wrapping sheet, and the inner surface of the vertical part of the outer wrapping sheet is in close contact with the third sealing ring.

Images