CN218385629U

CN218385629U - Battery cell and battery module

Info

Publication number: CN218385629U
Application number: CN202222488771.2U
Authority: CN
Inventors: 张旭; 付方凯; 何亚飞
Original assignee: Envision Power Technology Jiangsu Co Ltd; Envision Ruitai Power Technology Shanghai Co Ltd
Current assignee: Envision Power Technology Jiangsu Co Ltd; Envision Ruitai Power Technology Shanghai Co Ltd
Priority date: 2022-09-20
Filing date: 2022-09-20
Publication date: 2023-01-24
Anticipated expiration: 2032-09-20

Abstract

The utility model belongs to the technical field of the battery, a electricity core and battery module are disclosed. The battery cell comprises a shell and an explosion-proof valve, wherein the shell is provided with a mounting hole; the explosion-proof valve comprises an explosion-proof sheet and an inner protective film which are all installed in the installation hole, the inner protective film is located on one side, close to the inner wall face of the shell, of the explosion-proof sheet, the inner protective film can isolate the explosion-proof sheet from electrolyte in the shell, and the explosion-proof sheet and the inner protective film can be broken and decompressed when the internal pressure of the shell reaches a preset value. The explosion-proof valve of the battery core comprises the explosion-proof sheet which cannot be corroded by electrolyte inside the battery core, so that the reliability and the safety of the battery core are improved.

Description

Battery cell and battery module

Technical Field

The utility model relates to a battery technology field especially relates to an electricity core and battery module.

Background

With the rapid development of new energy industry, the permeability of new energy automobiles is gradually increased, people also put forward higher requirements on the safety performance and the electrical performance of power batteries, in the use process of the battery core, if severe working conditions, such as overcharge, collision, extrusion, high temperature and high humidity, occur, a large amount of gas and heat can be generated inside the battery core, if the pressure inside the battery core is not released in time, thermal runaway and even explosion can be caused, and thus the personal safety of users is threatened. Therefore, an explosion-proof valve is arranged on the square-shell battery cell, and the position of the explosion-proof valve can be an upper part or a lower part.

Traditional explosion-proof valve adopts the structure of explosion-proof piece with the individual layer protection film, to the square-shell electricity core that explosion-proof valve is located the bottom, electrolyte can direct contact bottom explosion-proof piece. The additive lithium hexafluorophosphate in the electrolyte can generate hydrofluoric acid and corrode the explosion-proof sheet, particularly the nicks in the explosion-proof sheet, so that the explosion-proof sheet can be exploded when the predetermined air pressure is not reached, and the service performance of the battery pack is influenced.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an electricity core, the explosion-proof piece in its explosion-proof valve can not corroded by the inside electrolyte of electricity core, has improved reliability, the security and the use of electricity core and has experienced.

To achieve the purpose, the utility model adopts the following technical proposal:

the battery cell comprises a shell and an explosion-proof valve, wherein the shell is provided with a mounting hole; the explosion-proof valve comprises an explosion-proof sheet and an inner protective film which are all installed in the installation hole, the inner protective film is located on one side, close to the inner wall face of the shell, of the explosion-proof sheet, the inner protective film can isolate the explosion-proof sheet from electrolyte in the shell, and the explosion-proof sheet and the inner protective film can be broken and decompressed when the internal pressure of the shell reaches a preset value.

Optionally, the explosion-proof valve further comprises an outer protection film mounted in the mounting hole, and the outer protection film is positioned on one side of the explosion-proof sheet far away from the inner wall surface of the shell.

Optionally, the outer protective film covers the mounting hole, and the inner protective film covers the explosion-proof sheet.

Optionally, the thickness of the inner protective film is not greater than the thickness of the explosion-proof sheet.

Optionally, nicks are formed on both the explosion-proof sheet and the inner protective film, and the nicks are in a curve shape.

Optionally, the scoring depth is D1, and D1 is more than or equal to 0.01mm and less than or equal to 0.5mm.

Optionally, the mounting holes are provided in the bottom wall and/or the side walls of the housing.

Optionally, the gap between the explosion-proof sheet and the inner protective film is D2, and D2 is greater than or equal to 0.01mm and less than or equal to 0.5mm.

Optionally, the mounting holes and the explosion-proof valves are provided with a plurality of mounting holes which are distributed at intervals, and the explosion-proof valves are mounted on the mounting holes in a one-to-one correspondence manner.

Another object of the present invention is to provide a battery module, which includes the above battery cell.

Has the advantages that:

install explosion-proof valve on the casing of this electric core, a pressure release for the inside of electric core, explosion-proof valve is further including installing explosion-proof piece and the interior protection film of mounting hole department on the casing, interior protection film sets up in one side that explosion-proof piece is close to the casing inner wall face, also the interior protection film sets up between explosion-proof piece and the inside electrolyte of casing, can prevent inside electrolyte direct contact and corrode explosion-proof piece, and interior protection film and explosion-proof piece homoenergetic break and the pressure release when casing internal pressure reachs the default, under the condition that does not influence explosion-proof valve pressure release performance, make explosion-proof valve and the electric core that has this explosion-proof valve safe and reliable more.

Drawings

Fig. 1 is a schematic diagram of a battery cell in an embodiment according to an embodiment of the present invention;

fig. 2 is an exploded schematic view of a battery cell in an embodiment according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view of an explosion-proof valve according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a battery cell in another embodiment provided in the present disclosure;

fig. 5 is an explosion diagram of a battery cell in another embodiment provided by the specific embodiment of the present invention.

In the figure:

100. a housing; 110. mounting holes; 120. a liquid injection hole;

200. an explosion-proof valve; 210. an explosion-proof sheet; 211. scoring; 220. an inner protective film; 230. and an outer protective film.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It should be further noted that, for the convenience of description, only some of the structures associated with the present invention are shown in the drawings, not all of them.

In the description of the present invention, unless otherwise explicitly specified or limited, the terms "connected", "connected" and "fixed" are to be construed broadly, e.g., as being fixedly connected, detachably connected, or integrated; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

Example one

Referring to fig. 1 to fig. 2, in the present embodiment, the battery cell includes a casing 100 and an explosion-proof valve 200, and the casing 100 is provided with a mounting hole 110; the explosion-proof valve 200 comprises an explosion-proof sheet 210 and an inner protection film 220 which are both installed in the installation hole 110, the inner protection film 220 is located on one side of the explosion-proof sheet 210 close to the inner wall surface of the casing 100, the inner protection film 220 can isolate the explosion-proof sheet 210 from electrolyte in the casing 100, and the explosion-proof sheet 210 and the inner protection film 220 can be broken and decompressed when the internal pressure of the casing 100 reaches a preset value.

In the electrical core of the embodiment, the housing 100 of the electrical core is provided with the explosion-proof valve 200, which is used for pressure relief inside the electrical core, the explosion-proof valve 200 further includes an explosion-proof sheet 210 and an inner protection film 220 installed on the housing 100 at the installation hole 110, the inner protection film 220 is disposed on one side of the explosion-proof sheet 210 close to the inner wall surface of the housing 100, that is, the inner protection film 220 is disposed between the explosion-proof sheet 210 and the electrolyte inside the housing 100, the explosion-proof sheet 210 and the electrolyte inside the housing 100 can be isolated, the inner electrolyte is prevented from directly contacting and corroding the explosion-proof sheet 210, and the inner protection film 220 and the explosion-proof sheet 210 can both rupture and release pressure when the internal pressure of the housing 100 reaches a preset value, so that the explosion-proof valve 200 and the electrical core with the explosion-proof valve 200 are safer and more reliable under the condition that the pressure relief performance of the explosion-proof valve 200 is not affected.

Optionally, the mounting hole 110 is formed in the bottom wall and/or the side wall of the casing 100, and the explosion-proof valve 200 in this embodiment is mounted on the mounting hole 110 on the bottom surface of the casing 100, so that the battery cell can be depressurized from the bottom surface. The explosion-proof sheet 210, the inner protective film 220 and the outer protective film 230 in this embodiment are made of metal, and the explosion-proof sheet 210 is fixed to the mounting hole 110 by welding or bonding. The explosion-proof sheet 210, the inner protection film 220 and the outer protection film 230 made of metal can also ensure that the explosion-proof valve 200 does not affect the overall strength of the electrical core casing 100 on the premise of ensuring a certain pressure relief capacity, and specifically, the selection of the metal material can be selected by a person skilled in the art according to specific requirements, and is not specifically limited here.

Referring to fig. 3, further, the thickness of the inner protection film 220 is not greater than the thickness of the rupture disk 210. The explosion-proof valve 200 that sets up like this can guarantee that the maximum pressure that interior protection film 220 can bear can not exceed the maximum pressure that explosion-proof piece 210 can bear, also is the pressure release pressure of explosion-proof valve 200 for the pressure release pressure of explosion-proof valve 200 is not influenced, has guaranteed that explosion-proof valve 200 can be at the default pressure release all the time, has guaranteed the stability and the reliability of explosion-proof valve 200 pressure release.

Specifically, both the explosion-proof sheet 210 and the inner protective film 220 are provided with a notch 211, and the notch 211 is in a curve shape. The nick 211 can form a weak area on the explosion-proof sheet 210 and the inner protective film 220, and can be broken and decompressed when the internal pressure of the battery cell reaches a preset value, so that the decompression mode is simple and rapid, and the manufacturing process is simple. The depth of the notch 211 in this embodiment is D1, and D1 is more than or equal to 0.01mm and less than or equal to 0.5mm. The depth of the notch 211 set in this way can ensure the pressure releasing capability of the explosion-proof sheet 210 and the inner protection film 220, the specific depth of the notch 211 should be determined by the pressure releasing pressure required by the explosion-proof valve 200, and a person skilled in the art can select notches 211 of different depths according to the pressure releasing pressure, which is not limited in particular.

As a preferred embodiment, the inner protection film 220 covers the explosion-proof sheet 210, that is, the coverage area of the inner protection film 210 is not less than that of the explosion-proof sheet 210. The inner protection film 220 with a larger coverage area than that of the explosion-proof sheet 210 can completely cover the explosion-proof sheet 210, and further prevent the explosion-proof sheet 210 from being corroded by electrolyte inside the battery cell.

With continued reference to fig. 3, optionally, the gap between the anti-explosion plate 210 and the inner protection film 220 is D2, and D2 is greater than or equal to 0.01mm and less than or equal to 0.5mm. That is, the gap between the rupture disk 210 and the inner protective film 220 can be controlled to be 0.01mm to 0.5mm. Be provided with certain clearance between explosion-proof piece 210 and interior protection film 220, can prevent to be blockked by explosion-proof piece 210 when protection film 220 is broken by the deformation of electric core internal pressure jack-up including, the phenomenon that electric core internal pressure surpassed the default when interior protection film 220 broke takes place, has further guaranteed the security of electric core.

The explosion-proof valve 200 further includes an outer protective film 230 mounted to the mounting hole 110, the outer protective film 230 being located on a side of the explosion-proof sheet 210 away from the inner wall surface of the housing 100. The outer protective film 230 covers the explosion-proof sheet 210 and covers an area not smaller than the area of the mounting hole 110. The outer protection film 230 can prevent the explosion-proof sheet 210 from being punctured by foreign objects, prevent the occurrence of accidental rupture and pressure release, and ensure the reliability and safety of the explosion-proof valve 200.

Further, a plurality of mounting holes 110 and explosion-proof valves 200 are provided, the mounting holes 110 are distributed at intervals, and the explosion-proof valves 200 are mounted on the mounting holes 110 in a one-to-one correspondence manner. The number of the explosion-proof valves 200 is selected by a person skilled in the art according to the size of the battery cell, the required pressure relief pressure, and the size of the pressure relief exhaust space that can be used after the battery cell is installed, and the embodiment is not particularly limited.

The embodiment also provides a battery module, and the battery module comprises the battery core.

Example two

In the present embodiment, the difference from the above embodiments is only that the mounting hole 110 and the explosion-proof valve 200 in the present embodiment are both disposed on the side surface of the battery cell, that is, the explosion-proof valve 200 is disposed to enable the battery cell to be depressurized from the side surface.

The specific positions of the explosion-proof valve 200 and the mounting hole 110 are selected, and after the battery cell is assembled and installed on a device using the battery cell, such as a battery module, a storage battery pack, an electric vehicle, and an electric bicycle, the position of a pressure relief exhaust space left on the periphery of the battery cell is determined, the mounting hole 110 and the explosion-proof valve 200 are also on the side surface of the exhaust space on the side surface, the exhaust space is on the bottom surface, the mounting hole 110 and the explosion-proof valve 200 are also on the bottom surface of the exhaust space, of course, the mounting hole 110 may be provided on both the side wall and the bottom wall of the housing 100, and no specific limitation is made here.

It is obvious that the above embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Numerous obvious variations, rearrangements and substitutions will now occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. 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 claims of the present invention.

Claims

1. A battery cell, comprising:

the device comprises a shell (100), wherein a mounting hole (110) is formed in the shell (100);

explosion-proof valve (200), explosion-proof valve (200) including all install in explosion-proof piece (210) and interior protection film (220) of mounting hole (110), interior protection film (220) are located being close to of explosion-proof piece (210) one side of casing (100) internal wall face, just interior protection film (220) can with explosion-proof piece (210) with electrolyte in casing (100) is kept apart, explosion-proof piece (210) with interior protection film (220) are in can break and the pressure release when casing (100) internal pressure reachs the default.

2. The electrical core of claim 1, wherein the explosion-proof valve (200) further comprises an outer protective film (230) mounted to the mounting hole (110), and the outer protective film (230) is located on a side of the explosion-proof sheet (210) away from an inner wall surface of the housing (100).

3. The electrical core of claim 2, wherein the outer protective film (230) covers the mounting hole (110), and the inner protective film (220) covers the rupture disc (210).

4. The electrical core of any of claims 1 to 3, wherein the thickness of the inner protective film (220) is not greater than the thickness of the rupture disc (210).

5. The battery cell of any one of claims 1 to 3, wherein the explosion-proof sheet (210) and the inner protective film (220) are both provided with a notch (211), and the notch (211) is in a curve shape.

6. The cell of claim 5, wherein the score (211) has a depth D1, D1 being 0.01mm ≦ D1 ≦ 0.5mm.

7. The electrical core according to any of claims 1 to 3, wherein the mounting hole (110) opens in a bottom wall and/or a side wall of the casing (100).

8. The battery cell of any of claims 1 to 3, wherein a gap between the explosion-proof sheet (210) and the inner protective film (220) is D2, and D2 is greater than or equal to 0.01mm and less than or equal to 0.5mm.

9. The battery cell of any one of claims 1 to 3, wherein a plurality of the mounting holes (110) and the explosion-proof valves (200) are provided, the plurality of mounting holes (110) are distributed at intervals, and the plurality of explosion-proof valves (200) are mounted on the plurality of mounting holes (110) in a one-to-one correspondence manner.

10. A battery module comprising the battery cell of any one of claims 1-9.