CN212136567U

CN212136567U - Battery pack box, battery pack and electric vehicle

Info

Publication number: CN212136567U
Application number: CN202021211080.2U
Authority: CN
Inventors: 曲凡多; 任荣彬; 贾鹏; 金花; 瓮百川
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2020-06-24
Filing date: 2020-06-24
Publication date: 2020-12-11
Anticipated expiration: 2030-06-24

Abstract

The utility model relates to a battery package box, battery package and electric vehicle, battery package box is including main part (10) that is used for holding electric core, be formed with a plurality of pressure release holes (101) on main part (10), battery package box still establishes including pasting be used for covering a plurality ofly on main part (10) flexible rete (11) of pressure release hole (101). Like this, when electric core in the box takes place a large amount of exhaust of thermal runaway and even produces the detonation, the pressure accessible pressure release hole in the battery package box releases to the intermediate layer between flexible rete and the main part, then changes the increase accommodation space through the shape of flexible rete, slows down pressure increase rate, prevents effectively that the box from breaking because of pressure deformation, and can not increase the weight of battery package box, accords with lightweight design principle. In addition, can cancel the ventilative device that is equipped with on the current battery package box, avoid the box inside to receive outside moisture to influence, avoid the condensation risk.

Description

Battery pack box, battery pack and electric vehicle

Technical Field

The disclosure relates to the technical field of power batteries, in particular to a battery pack box body, a battery pack and an electric vehicle.

Background

Power batteries, especially ternary system lithium ion batteries, have higher energy density and endurance mileage, but can produce a large amount of combustible gas and heat when it takes place thermal runaway, and the detonation phenomenon takes place in the battery package, leads to the battery package box to crack because of gas pressure to burn through the battery package box. Among the correlation technique, set up explosion-proof valve, pressure balance valve etc. on the battery package box, nevertheless the effect is not good in practical application, and the pressure that inside detonation gas inflation produced can't in time be released, leads to the battery package box to break, and the flame in the battery package is along the outside burning of crack, leads to dangerous aggravation.

SUMMERY OF THE UTILITY MODEL

The first purpose of this disclosure is to provide a battery package box, this battery package box can solve the cracked technical problem of battery package box when electric core takes place thermal runaway.

A second object of the present disclosure is to provide a battery pack including the battery pack case provided by the present disclosure.

A third object of the present disclosure is to provide an electric vehicle including the battery pack provided by the present disclosure.

In order to achieve the above object, the present disclosure provides a battery pack case, including a main body for accommodating an electric core, a plurality of pressure relief holes are formed in the main body, and the battery pack case further includes a flexible film layer attached to the main body and used for covering the plurality of pressure relief holes.

Optionally, the flexible film layer is fixed to the main body in a sticking mode, and the battery pack box body further comprises a sticking fixing layer located between the flexible film layer and the side wall of the main body.

Optionally, the flexible film layer is configured as a stacked structure with multiple folds, and folds are provided between adjacent stacked structures.

Optionally, a weak area is formed on the flexible film layer, a plurality of pressing lines are arranged on the weak area, and the weak area has a thickened edge.

Optionally, the battery pack case further comprises a thermal insulation layer between the main body and the flexible film layer.

Optionally, the battery pack case further comprises a waterproof vent valve on the side wall of the main body.

Optionally, the gas in the battery pack case is a non-combustible gas, and the water content of the gas is less than 300 ppm.

Optionally, the battery pack box further comprises a fire filtering layer attached to the inner wall of the main body and used for sealing the pressure relief hole, and a plurality of air holes are formed in the fire filtering layer.

According to a second aspect of the present disclosure, a battery pack is further provided, which includes a battery core and a box body for accommodating the battery core, where the box body is the above battery pack box body.

According to a third aspect of the present disclosure, there is also provided an electric vehicle including the battery pack provided by the present disclosure.

Through above-mentioned technical scheme, when electric core in the box takes place a large amount of exhaust of thermal runaway and even produces the detonation, the intermediate layer between flexible rete and the main part is released to the accessible pressure release hole of pressure in the battery package box, then the shape through flexible rete changes the increase accommodation space, slows down pressure increase rate, prevents effectively that the box from breaking because of pressure deformation, and can not increase the weight of battery package box, accords with lightweight design principle. In addition, can cancel the ventilative device that is equipped with on the current battery package box, avoid the box inside to receive outside moisture to influence, avoid the condensation risk.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is an exploded view of a battery pack case provided in an exemplary embodiment of the present disclosure;

fig. 2 is a schematic structural view of a battery pack case body provided in an exemplary embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a flexible film layer of a battery pack case provided in an exemplary embodiment of the present disclosure;

fig. 4 is a schematic structural view of a weak area on a flexible film layer of a battery pack case provided by an exemplary embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a battery pack case provided in an exemplary embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of section A-A of FIG. 5;

FIG. 7 is an enlarged view of a portion of the structure of FIG. 6;

fig. 8 is an assembly view of a fire filter of a battery pack case according to an exemplary embodiment of the present disclosure;

fig. 9 is an exploded view of the installation of a fire filter of a battery pack case according to an exemplary embodiment of the present disclosure.

Description of the reference numerals

10-main body, 100-pressure relief cavity, 101-pressure relief hole, 11-flexible film layer, 111-crease, 112-weak area, 113-pressing line, 12-sticking fixed layer, 13-fire filtering layer, 130-air hole, 14-heat insulating layer and 2-waterproof ventilation valve.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, unless otherwise specified, the use of the terms of orientation such as "upper", "lower", "top" and "bottom" generally means that they are defined in the case of normal use of the battery pack case provided in the present disclosure, and specifically, reference may be made to the direction of the drawing shown in the drawings. "inner" and "outer" refer to the inner and outer of the contours of the corresponding elements, and moreover, where the following description refers to the accompanying drawings, like numerals in different drawings represent the same or similar elements, unless otherwise indicated.

The existing battery pack case is generally made of a plastic material such as SMC (thermosetting reinforced plastic) in order to achieve a lightweight design. When electric core takes place thermal runaway in the battery package, take place the detonation phenomenon, lead to battery package internal pressure to increase rapidly, battery package box takes place to warp under the pressure effect, when exceeding the deformation limit of box, leads to the box fracture. In order to solve the problem, two approaches are mainly used in the design process of the battery pack box body, one is to strengthen the structural strength of the box body to ensure that the box body has enough strength to bear pressure, but the weight of the box body is correspondingly increased, and the requirement on a strengthening structure is higher due to higher detonation pressure; secondly, a specific channel is designed to quickly release pressure, for example, an explosion-proof valve is additionally arranged, but the response speed of the explosion-proof valve is delayed, so that the cracking of the box body cannot be effectively prevented.

To solve the above problem, as shown in fig. 1 and fig. 2, the present disclosure provides a battery pack case, which includes a main body 10 for accommodating a battery core, a plurality of pressure relief holes 101 formed in the main body 10, and a flexible film layer 11 attached to the main body 10 for covering the plurality of pressure relief holes 101. Here, it should be noted that a plurality of pressure relief holes 101 may be formed in the top wall of the main body 10, and have a larger effective area, and the number of the pressure relief holes 101 may be increased as needed, and the pressure relief holes 101 are formed in the top wall as an example, which will be described in detail below. The flexible film layer 11 has good deformability, that is, has a flexible deformation space, and can reduce or delay the generation of pressure difference in the tank body. In addition, the pressure in the battery pack case can be adjusted by the deformation of the flexible film layer 11, for example, when the pressure in the battery pack case is greater than the external pressure, the flexible film layer 11 bulges outwards, the internal space is increased to reduce the pressure in the battery pack case, and the internal pressure and the external pressure are kept the same; when pressure in the battery package box is less than external pressure, flexible rete 11 is inwards shrink, reduces the pressure of inner space in order to increase battery package box, makes inside and outside pressure keep the same, and flexible rete 11 can not lead to fatigue failure because of the deformation, consequently, the battery package box that this disclosure provided need not to set up extra ventilative device.

Through above-mentioned technical scheme, when electric core in the box takes place a large amount of exhaust of thermal runaway and even produces the detonation, the pressure accessible pressure release hole 101 in the battery package box releases to the intermediate layer between flexible rete 11 and the main part 10, then changes the increase accommodation space through the shape of flexible rete 11, slows down pressure increase rate, prevents effectively that the box from breaking because of pressure deformation, and can not increase the weight of battery package box, accords with lightweight design principle. In addition, can cancel the ventilative device that is equipped with on the current battery package box, avoid the box inside to receive outside moisture to influence, avoid the condensation risk.

Specifically, the main body 10 may be configured as a rectangular structure, a side wall of the main body 10, on which a plurality of pressure relief holes 101 are formed, is recessed inward, the periphery of the flexible film 11 is attached to the side wall, and a pressure relief cavity 100 is formed between the flexible film 11 and the side wall. The gas exhausted from the pressure relief hole 101 enters the pressure relief cavity 100 to be relieved, and then acts on the flexible film 11 after the pressure relief cavity 100 is filled with the gas, so that the flexible film is deformed.

As shown in fig. 5 to 7, the flexible film 11 is adhesively fixed on the main body 10, and the battery pack case further includes an adhesive fixing layer 12 between the flexible film 11 and the side wall of the main body 10. The flexible film layer 11 may be a waterproof film, and the adhesive fixing layer 12 may be a butyl tape, which can stably fix the flexible film layer 11 on the main body 10. The body 10 may be a plastic plate or a metal plate, for example, an aluminum alloy or a steel plate.

The flexible film layer 11 itself is very ductile and can increase the surface area several times without breaking. Further, in the present disclosure, as shown in fig. 3, the flexible film 11 may be configured as a stacked structure that is folded many times, and a fold 111 is formed between adjacent stacked structures, that is, the flexible film 11 is subjected to a stacking and folding process, similar to the folding process of the disposable mask, the stacked structure of the flexible film can be unfolded under pressure to have a larger covering space, and can be unfolded in time to release pressure under the action of the deflagration gas, so as to prevent the rupture.

The volume of the accumulated gas generated in the battery pack box body far exceeds the bearing capacity of the deformation of the flexible film layer 11, the accumulated gas is broken, and in order to make the flexible film layer 11 directionally broken, as shown in fig. 4, a weak area 112 is formed on the flexible film layer 11, a plurality of pressing lines 113 are arranged on the weak area 112, the weak area 112 is provided with a thickened edge, the flexible film layer 11 is locally thinned through the design of the pressing lines 113, the pressing lines 113 can be cracked under the action of pressure, the outer contour of the weak area 112 is thickened, infinite cracking can be avoided, and the blasting area is controlled within a certain range. In other embodiments, be formed with the trompil on the flexible rete 11, additional extra waterproof ventilated membrane is in order to seal this trompil, has waterproof ventilative function, can balance internal and external pressure differential through waterproof ventilated membrane simultaneously under the battery package box normal use condition, when electric core emergence thermal runaway, can tear waterproof ventilated membrane down under the effect of pressure, carry out the pressure release.

In addition, when considering that the electric core is out of control thermally, the box body can be burnt, in order to prevent the flame from igniting the flexible film layer 11 through the pressure relief hole 101, as shown in fig. 8 and 9, the battery pack box body further comprises a fire filtering layer 13 attached to the inner wall of the main body 10 and used for sealing the pressure relief hole 101, and a plurality of air holes 130 are formed in the fire filtering layer 13. Thus, a fire filtering structure is added at the pressure relief hole 101, so that the fire can be prevented from spreading to the outside of the main body 10.

Further, as shown in fig. 1, the battery pack case provided by the present disclosure further includes a thermal insulation layer 14 located between the main body 10 and the flexible film layer 11, so that the influence of high temperature in the case on the components located above the case can be reduced. In other embodiments, the thermal insulation layer 14 is an insulation material filled in the pressure relief cavity described above, such as a ceramic fiber sheet, a fire blanket, and the like, and the thermal insulation layer 14 can also play a certain role in thermal insulation under normal operation of the battery pack.

In addition, the gas in the battery pack box body provided by the disclosure is dilute oxygen or oxygen-free, the water content of the gas is less than 300ppm, and the gas composition in the battery pack box body can be controlled in a ventilation mode before the battery pack box body is finally packaged, so that the gas in the box body is dry, and the gas in the box body can not generate condensation when the battery pack box body is subjected to damp and hot environment change or high and low temperature change, so that the danger of short circuit caused by insulation failure of electric connection in the battery pack box body due to condensed water vapor is avoided; the oxygen content of gas in the box is reduced, for example, the gas in the box is mainly non-combustible gas such as carbon dioxide, nitrogen, argon and the like, oxygen generated by the battery cell can be diluted, so that the gas in the box is not fully combusted, the heat production is reduced, and the damage to the box and other parts in the box is reduced.

The battery pack box that this disclosure provided can with the explosion-proof valve or waterproof breather valve that traditional battery pack box was equipped with or have explosion-proof valve of waterproof ventilative function etc. and use jointly, as an exemplary embodiment of this disclosure, as shown in fig. 4, the battery pack box that this disclosure provided still includes waterproof breather valve 2 that is located main part 10 lateral wall, under normal use operating mode, can guarantee that the internal and external pressure of battery pack box is balanced, guarantee reliable sealed, when the battery pack is unusual, avoid plus the unable rapid pressure release of valve through the deformation of flexible rete 11, lead to the battery pack box to break.

According to the second aspect of the present disclosure, there is also provided a battery pack, which includes a battery cell and a case for accommodating the battery cell, wherein the case is the above-described battery pack case.

According to a third aspect of the present disclosure, there is also provided an electric vehicle including the battery pack provided by the present disclosure. The electric vehicle and the battery pack have all the advantages of the battery pack box introduced above, and redundant description is not repeated here.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. The utility model provides a battery package box, is including main part (10) that is used for holding electric core, its characterized in that, be formed with a plurality of pressure release holes (101) on main part (10), battery package box still including paste establish be used for covering a plurality ofly on main part (10) flexible rete (11) of pressure release hole (101).

2. The battery pack case according to claim 1, wherein the flexible film layer (11) is adhesively fixed to the main body (10), and the battery pack case further comprises an adhesive fixing layer (12) between the flexible film layer (11) and the side wall of the main body (10).

3. The battery pack case according to claim 1, wherein the flexible film layer (11) is constructed in a stacked structure with a plurality of folds, and folds (111) are formed between adjacent stacked structures.

4. The battery pack case according to claim 1, wherein a weak area (112) is formed on the flexible film layer (11), a plurality of pressing lines (113) are provided on the weak area (112), and the weak area (112) has a thickened edge.

5. The battery pack case according to claim 1, further comprising a thermal insulation layer (14) between the main body (10) and the flexible film layer (11).

6. The battery pack case according to claim 1, further comprising a waterproof vent valve (2) on a side wall of the main body (10).

7. The battery pack case according to claim 1, wherein the gas in the battery pack case is a non-combustible gas, and the water content of the gas is less than 300 ppm.

8. The battery pack case according to any one of claims 1 to 7, further comprising a fire filter layer (13) attached to an inner wall of the main body (10) for closing the pressure relief hole (101), wherein a plurality of air holes (130) are formed in the fire filter layer (13).

9. A battery pack comprising a battery cell and a case for housing the battery cell, wherein the case is a battery pack case according to any one of claims 1 to 8.

10. An electric vehicle comprising a battery pack, characterized in that the battery pack is the battery pack according to claim 9.