CN210576159U

CN210576159U - Laminate polymer battery structure with explosion-proof function

Info

Publication number: CN210576159U
Application number: CN201921270096.8U
Authority: CN
Inventors: 叶敏华; 叶嘉慧
Original assignee: Chung Pak Guangdong Battery Industrial Co ltd; CHUNG PAK INVESTMENT Ltd
Current assignee: Chung Pak Guangdong Battery Industrial Co ltd; CHUNG PAK INVESTMENT Ltd
Priority date: 2019-08-06
Filing date: 2019-08-06
Publication date: 2020-05-19
Anticipated expiration: 2029-08-06

Abstract

The utility model provides a soft package battery structure with explosion-proof function, which comprises a shell and a wrapping battery cell arranged in the shell, wherein the shell comprises an upper layer aluminum-plastic film and a lower layer aluminum-plastic film, an upper groove formed into a whole with the upper layer aluminum-plastic film is arranged on the upper layer aluminum-plastic film, a lower groove formed into a whole with the lower layer aluminum-plastic film is arranged on the lower layer aluminum-plastic film, and the battery cell is placed in a closed accommodating cavity formed by the upper groove and the lower groove; the lower groove is provided with a bottom wall and an annular side wall, and at least one explosion-proof indentation is arranged on the annular side wall. The utility model discloses meetting overdischarge or short circuit, the inside gas expansion of battery, battery case produces the bulge outward, and then extrudes explosion-proof indentation for explosion-proof indentation department at first breaks, and the gas in the battery is let out and is realized explosion-proofly.

Description

Laminate polymer battery structure with explosion-proof function

Technical Field

The utility model belongs to the technical field of small-size soft packet of lithium cell, concretely relates to soft packet of battery structure with explosion-proof function.

Background

With the diversification of life and the progress of science and technology, the demand for a rechargeable small battery is increasing day by day, in the field of rechargeable small batteries, rechargeable lithium ion batteries and soft-package lithium batteries are widely applied to sustainable battery equipment and small light-emitting equipment, such as mobile cards, wireless earphones, noctilucent floats, hearing aids and the like, in the extremely small equipment, the capacity of the battery is also highly required, the volumetric specific energy density is a key factor, and due to the requirement on the volume and the capacity of the rechargeable lithium ion battery, in order to reduce the volume of the battery and ensure the application function of the battery, a spiral winding battery core is generally adopted at present, the volumetric energy density of the battery is increased, the battery is wrapped by a steel shell, and the sealing performance and the long-term use performance of the battery are difficult to ensure.

Along with wearing equipment wide application, the requirement to small-size lithium cell is coming more and more, the present wearing equipment built-in power supply is mainly for chargeable button lithium cell, but current button cell shell is the steel-shelled parcel, chinese patent application CN201611086886.1 for example discloses a novel coiling formula button cell, battery case includes casing and upper cover down, install insulating cement between casing and the upper cover down, the upper surface of aluminium foil passes through the fixed connection upper cover of mode spot welding, the below of aluminium foil is equipped with insulating gasket and winding, the winding is installed in battery case's inside, the winding includes positive plate, the negative pole piece, barrier film and winding core, the upper surface of casing down is connected to insulating gasket's base.

For another example, CN201710663558.1 discloses a button lithium battery with an open-cell type pole piece, which comprises a negative electrode cover, a positive electrode shell, an insulating sealing ring arranged between the outer edge of the negative electrode cover and the upper closing-in of the positive electrode shell, a lithium ion negative electrode piece, a battery diaphragm and a positive electrode piece sequentially arranged in the positive electrode shell from top to bottom, a pole piece steel ring arranged between the positive electrode piece and the positive electrode shell, an electrolyte filled in the positive electrode shell, and at least one open cell arranged on the positive electrode piece.

The button cell in the prior art has high requirements for the package of the cell, the lead welding of the cell is easy to weld through the shell to cause liquid leakage, the steel shell material is not corrosion-resistant to the electrolysis of the lithium cell, the welding spot is corroded to fall off to cause the failure of the cell, the liquid leakage or explosion of the cell is easy to occur, and the personal safety is seriously influenced.

Because wearable equipment needs to improve continuation of the journey, can add to the at utmost to the active material of battery to can accomplish more and more thin with the shell, in order to adapt to miniaturized design, so need solve the explosion-proof problem under the small-size button lithium cell overdischarge or the short circuit condition.

SUMMERY OF THE UTILITY MODEL

To prior art's defect, the utility model provides a laminate polymer battery structure with explosion-proof function meets overdischarge or short circuit, and the inside gas expansion of battery, battery case produce the bulge, and then extrude explosion-proof indentation for explosion-proof indentation department is at first broken, and gas in the battery is let out and is realized explosion-proofly.

In order to achieve the purpose, the utility model provides a soft package battery structure with explosion-proof function, which comprises a shell and a package battery cell arranged inside the shell, wherein the shell comprises an upper layer aluminum-plastic film and a lower layer aluminum-plastic film, an upper groove formed integrally with the upper layer aluminum-plastic film is arranged on the upper layer aluminum-plastic film, a lower groove formed integrally with the lower layer aluminum-plastic film is arranged on the lower layer aluminum-plastic film, and the battery cell is placed in a closed accommodating cavity formed by the upper groove and the lower groove; the lower groove is provided with a bottom wall and an annular side wall, and at least one explosion-proof indentation is arranged on the annular side wall.

According to another specific embodiment of the present invention, the thickness of the upper aluminum-plastic film is 0.07mm to 0.15mm, and the thickness of the lower aluminum-plastic film is 0.07mm to 0.15 mm;

preferably, the thickness of the upper aluminum plastic film and the lower aluminum plastic film is the same, and the thickness of the upper aluminum plastic film and the lower aluminum plastic film is 0.10mm to 0.12mm, for example, the thickness of the upper aluminum plastic film and the lower aluminum plastic film is 0.11 mm.

According to the utility model discloses a another concrete implementation way, the degree of depth of explosion-proof indentation is 10% to 50% of lower floor's plastic-aluminum composite film thickness, and the degree of depth of specific for example explosion-proof indentation is 30% of lower floor's plastic-aluminum composite film thickness.

According to another embodiment of the present invention, the height of the explosion-proof indentation is 10% to 90% of the annular side wall, and the height of the explosion-proof indentation is 40% of the annular side wall, preferably, the explosion-proof indentation is located in the central region of the annular side wall in the height direction.

According to another embodiment of the present invention, the depth of the lower groove is set to be not less than the depth of the upper groove.

Preferably, the depth of the lower groove is 3 times the depth of the upper groove.

As an extension of the present invention, the number of the explosion-proof indentations is 2-4, for example 3.

The projection shape of the explosion-proof indentation can be selected to be cross-shaped, straight-line-shaped, field-shaped or well-shaped, and other similar shapes.

Further, the cross section of the explosion-proof indentation is rectangular, V-shaped, conical or U-shaped.

As another extension of the utility model, the upper layer of aluminum plastic film is positioned on the upper groove and has an upper sealing edge, the lower layer of aluminum plastic film is positioned on the lower groove and has a lower sealing edge, the upper sealing edge and the lower sealing edge after packaging are bent to the outer side of the annular side wall in the lower groove, and the upper sealing edge, the lower sealing edge and the annular side wall are in contact or not in contact, wherein, explosion-proof indentations are also arranged on the upper sealing edge and/or the lower sealing edge; it should be noted that only one explosion-proof indentation needs to be arranged at the same position.

The utility model discloses possess following beneficial effect:

the utility model adopts the soft package shell, has excellent sealing performance, has larger capacity under the same volume and has the advantage of light weight;

the utility model discloses in be provided with explosion-proof indentation, meetting overdischarge or the short circuit condition, the inside gas inflation of battery, battery case produces the bulge outward, and then extrudes explosion-proof indentation for explosion-proof indentation department breaks at first, and gas in the battery is let out and is realized explosion-proofly, and battery fail safe nature is high.

The present invention will be described in further detail with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic diagram of the structure of the soft package battery of the present invention;

FIG. 2 is a schematic structural view of the lower aluminum-plastic film of the present invention before heat sealing;

FIG. 3 is a schematic cross-sectional view of an explosion-proof indentation;

FIG. 4 is a schematic view of the expanded state of the annular sidewall in the lower groove;

wherein the reference numbers are as follows:

housing 1

Upper layer aluminum plastic film 11

Lower aluminum plastic film 12

Upper groove 13

Lower groove 14

Explosion-proof indentation 2

Detailed Description

As shown in fig. 1-4, a pouch battery structure with an explosion-proof function includes a housing 1 and a wrapping cell.

The shell 1 adopts the soft packet of casing of plastic-aluminum complex film, and it includes upper aluminium-plastic film 11, lower floor's plastic-aluminum membrane 12, has the upper groove 13 rather than forming an organic whole on upper aluminium-plastic film 11, has the lower groove 14 rather than forming an organic whole on lower floor's plastic-aluminum membrane 12, and upper groove 13, lower groove 14 coincide each other, form airtight holding chamber after the two encapsulates, and the package electricity core is located airtight holding intracavity.

Wherein, the thickness of the upper aluminum-plastic film 11 is the same as that of the lower aluminum-plastic film 12, and both are 0.11 mm; further, the depth of the upper groove 13 is smaller than the depth of the lower groove 14, for example, the depth of the lower groove 14 is 3 times the depth of the upper groove 13, and specifically, the depth of the lower groove 14 is preferably not more than 5 mm.

Upper groove 13 is the cylindricality recess with lower groove 14, and it has diapire and annular side wall, wherein is provided with at least one explosion-proof indentation 2 on lower groove 14, and wherein explosion-proof indentation 2's shape can be for cross, a font, field font or groined type etc. the utility model discloses explain for the example with be provided with three explosion-proof indentation 2 of cross on lower groove 14's annular side wall:

fig. 4 shows the lower groove 14 in an expanded state with three cross-shaped explosion-proof indentations 2 spaced on the annular sidewall of the lower groove 14;

referring to fig. 1 and 2, in the height direction, the height of the explosion-proof indentation 2 is 40% of the annular side wall on the lower groove 14, and the explosion-proof indentation 2 is located in the central upper region of the annular side wall, and further, the depth of the explosion-proof indentation 2 is 30% of the thickness of the lower aluminum-plastic composite film.

Referring to fig. 3, the cross-sectional shape of the explosion-proof indentation 2 can be rectangular, V-shaped, conical, U-shaped, U-like, etc., and is selected according to actual design.

The utility model discloses an in other preferred examples, it has the upper seal edge to be located upper groove 13 at upper strata plastic-aluminum membrane 11, lower floor's plastic-aluminum membrane 12 is located lower groove 14 and has lower seal edge, the upper seal edge after the encapsulation is accomplished, the outside of lower seal edge bending to the annular lateral wall in the lower groove 14, the upper seal edge, contact between lower seal edge and the annular lateral wall, wherein, also can set up explosion-proof indentation 2 on upper seal edge or lower seal edge, at this moment, on the inside and outside each layer packaging film of same position, only need set up an explosion-proof indentation 2 can.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the scope of the invention. Any person skilled in the art can make some modifications without departing from the scope of the invention, i.e. all equivalent modifications made according to the invention are intended to be covered by the scope of the invention.

Claims

1. A soft package battery structure with an explosion-proof function comprises a shell and a winding battery cell arranged in the shell, and is characterized in that the shell comprises an upper layer aluminum-plastic film and a lower layer aluminum-plastic film, wherein the upper layer aluminum-plastic film is provided with an upper groove formed into a whole with the upper layer aluminum-plastic film, the lower layer aluminum-plastic film is provided with a lower groove formed into a whole with the lower layer aluminum-plastic film, and the battery cell is placed in a closed accommodating cavity formed by the upper groove and the lower groove; the lower groove is provided with a bottom wall and an annular side wall, and at least one explosion-proof indentation is arranged on the annular side wall.

2. The pouch cell structure having an explosion-proof function according to claim 1, wherein the thickness of the upper aluminum-plastic film is 0.07mm to 0.15mm, and the thickness of the lower aluminum-plastic film is 0.07mm to 0.15 mm.

3. The pouch cell structure having an explosion-proof function according to claim 1, wherein the depth of the explosion-proof indentation is 10 to 50% of the thickness of the lower aluminum-plastic composite film.

4. The pouch cell structure having an explosion-proof function according to claim 1, wherein the height of the explosion-proof indentation is 10 to 90% of the annular sidewall.

5. An explosion proof pouch cell structure according to claim 1, wherein the depth of said lower groove is set to be not less than the depth of said upper groove.

6. An explosion proof pouch cell structure as defined in claim 5, wherein the depth of said lower groove is 3 times the depth of said upper groove.

7. The pouch cell structure with explosion-proof function according to any one of claims 1 to 6, wherein the number of the explosion-proof indentations is 2 to 4.

8. The structure of the pouch battery with the explosion-proof function according to claim 7, wherein the projection shape of the explosion-proof indentation is a cross shape, a straight line shape, a field shape or a well shape.

9. The pouch cell structure with the explosion-proof function according to claim 8, wherein the cross-sectional shape of the explosion-proof indentation is rectangular, V-shaped, conical or U-shaped.

10. The explosion-proof pouch cell structure as claimed in any one of claims 1 to 6, wherein the upper aluminum-plastic film layer is located in the upper groove and has an upper sealing edge, the lower aluminum-plastic film layer is located in the lower groove and has a lower sealing edge, the upper and lower sealing edges after packaging are bent to the outer side of the annular sidewall in the lower groove, and the upper and lower sealing edges are in contact with or not in contact with the annular sidewall, wherein the explosion-proof indentations are also provided on the upper and/or lower sealing edges.