CN220420810U - Explosion-proof device, end cover and battery - Google Patents

Abstract

The utility model discloses an explosion-proof device, an end cover and a battery, wherein the explosion-proof device comprises a device main body and a phase change material, and the device main body is configured to be arranged on the end cover of the battery; the phase change material is used for changing into a gaseous state after being heated, is arranged in the device main body, and is a solid phase change material which is solid at normal temperature. According to the utility model, the explosion-proof device can be accelerated to reach the gas pressure required by opening by the aid of the phase-change gas, so that the explosion-proof device can quickly react to open the exhaust when the battery fails. And the phase change material can absorb heat in the phase change process, so that the temperature of the battery cell is reduced. From this can effectively avoid the local high temperature department in electric core middle part to appear bursting phenomenon to avoid electric core explosion, reach the explosion-proof effect of pressure release, improved the security of battery greatly.

Description

Explosion-proof device, end cover and battery

Technical Field

The utility model relates to the technical field of batteries, in particular to an explosion-proof device, an end cover and a battery.

Background

In order to avoid safety problems caused by temperature rise, such as fire, explosion and other safety accidents, the battery is provided with an explosion-proof valve. The explosion-proof valve is generally arranged at the end part of the battery and needs to reach a certain pressure to be opened.

Because the battery end has a certain distance from the inside of the battery cell, gas needs a certain time to flow from the inside of the battery cell to the battery end, so that the high temperature of the middle part of the battery cell can occur, the explosion-proof valve can not be opened in time due to insufficient pressure, and the explosion phenomenon can occur at the local high temperature of the middle part of the battery cell.

Accordingly, there is a need for an explosion protection device, end cap, and battery that at least partially address the above issues.

Disclosure of Invention

A series of concepts in a simplified form are introduced in the summary of the utility model, which will be described in further detail in the detailed description. The summary of the utility model is not intended to limit the critical and essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

To at least partially solve the above problems, the present utility model provides an explosion-proof apparatus for a battery, the explosion-proof apparatus comprising:

a device body configured to be disposed at an end cap of the battery; and

the phase change material is used for changing into a gaseous state after being heated, the phase change material is arranged in the device main body, and the phase change material is a solid phase change material which is solid at normal temperature.

Optionally, the solid phase change material sublimates in a temperature range of 80 ℃ to 300 ℃.

Optionally, the solid phase change material is configured as particles, which are packed within a covering having a gas permeable structure.

Optionally, the phase change material comprises a solid state hydrofluoroether.

Optionally, the device body is provided with a mounting hole, and the phase change material is disposed in the mounting hole.

Optionally, the explosion-proof device further includes a snap-fit cover openably connected to the first side of the device body and covering the device body, the device body having a first side and a second side in a first direction parallel to a thickness direction of the end cap, the mounting hole being open at least at the first side.

Optionally, the mounting hole is open at both the first side and the second side, and the explosion-proof device further comprises a sealing member disposed at the second side and sealing the mounting hole; or the mounting hole is a blind hole closed at the second side.

Optionally, the explosion-proof device further comprises a snap-fit cover connected to the first side of the device body and covering the device body, the mounting hole being open at least at the first side.

Optionally, the device body is provided with an exhaust hole, the exhaust hole penetrates through the device body in a direction perpendicular to the end cover, the exhaust hole has a first projection area S1 on a plane where the end cover is located, and the phase change material has a second projection area S2, s2= (20% -25%) S1 on the plane where the end cover is located.

Optionally, the number of the exhaust holes is more than two, and more than two exhaust holes are arranged around the phase change material.

Optionally, the phase change material is centrally disposed on the device body in a second direction perpendicular to a thickness direction of the end cap.

According to another aspect of the present utility model there is provided an end cap for a battery, the end cap comprising an anti-explosion device according to any one of the above aspects, the anti-explosion device being embedded in the end cap.

Optionally, the end cap has an end cap opening, and at least a device body of the explosion proof device is located within the end cap opening and does not protrude from the end cap.

According to another aspect of the present utility model, there is provided a battery including:

a battery case formed with a cavity;

an end cap covering to at least one end of the battery case;

the battery cell is positioned in the containing cavity; and

an explosion proof device according to any one of the preceding claims, the explosion proof device being disposed on and embedded in the end cap.

According to the explosion-proof device and the battery with the same, the phase-change material which can be changed from a solid state to a gas state after being heated is arranged in the explosion-proof device, when the battery breaks down to generate a large amount of heat, the heat can be quickly transferred to the end cover and the explosion-proof device, so that the phase-change material is quickly heated to be subjected to phase change, the phase-change gas is relatively close to the buckling cover, and a part of gas generated in the battery core and the phase-change gas can jointly act on the buckling cover, so that the buckling cover is opened, and the explosion-proof device is opened.

The phase-change gas generated by the phase-change material can increase the gas pressure at the explosion-proof device, and is matched with the gas generated in the battery cell to promote the opening of the explosion-proof device. By means of the aid of the phase-change gas, the explosion-proof device can be accelerated to reach the gas pressure required for opening, so that the explosion-proof device can quickly react to open the exhaust when the battery fails. From this can effectively avoid the local high temperature department in electric core middle part to appear bursting phenomenon to avoid electric core explosion, reach the explosion-proof effect of pressure release, improved the security of battery greatly.

And the phase change material can absorb heat in the phase change process, so that the temperature of the battery cell is reduced, the explosion of the battery cell is further avoided, and the safety of the battery is higher.

Drawings

The following drawings are included to provide an understanding of the utility model and are incorporated in and constitute a part of this specification. Embodiments of the present utility model and their description are shown in the drawings to explain the principles of the utility model.

In the accompanying drawings:

fig. 1 is a perspective view of a battery according to the prior art;

fig. 2 is a perspective view of a portion of the battery shown in fig. 1;

fig. 3 is a side view of an end cap of a battery according to the present utility model, wherein the snap cap is not shown;

FIG. 4 is a cross-sectional view of the end cap taken along line A-A of FIG. 3;

fig. 5 is an enlarged view of a portion of the explosion-proof apparatus shown in fig. 4.

Reference numerals illustrate:

1 cell

2 outer casing

3 end cap

4 explosion-proof valve

5 device body

6 exhaust holes

7 buckling cover

10 end cap

11 end cap mouth

20 explosion-proof device

21 device body

22 snap-fit cover

23 exhaust holes

24 phase change material

25 mounting holes

26 seal

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present utility model. It will be apparent, however, to one skilled in the art that the utility model may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the utility model.

In the following description, a detailed description will be given for the purpose of thoroughly understanding the present utility model. It will be apparent that embodiments of the utility model may be practiced without limitation to the specific details that are familiar to those skilled in the art. Preferred embodiments of the present utility model are described in detail below, however, the present utility model may have other embodiments in addition to these detailed descriptions.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present utility model. As used herein, the singular is intended to include the plural unless the context clearly indicates otherwise. Furthermore, it will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Ordinal numbers such as "first" and "second" cited in the present utility model are merely identifiers and do not have any other meaning, such as a particular order or the like. Also, for example, the term "first component" does not itself connote the presence of "second component" and the term "second component" does not itself connote the presence of "first component".

It should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and the like are used herein for illustrative purposes only and are not limiting.

Exemplary embodiments according to the present utility model will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It should be appreciated that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art.

As shown in fig. 1 and 2, an existing battery 1 generally includes a case 2, an end cap 3, and a battery cell. An end cap 3 is provided at the end of the housing 2, and the battery cell is provided in the housing 2 and covered by the end cap 3. The temperature rise can appear in the battery cell in a short time because of the fault, and the heat can not be timely outwards diffused by the heat insulation of the shell 2, and particularly, the heat insulation is more obvious when the shell 2 is an aluminum shell. The battery 1 is provided with an explosion-proof valve 4 to avoid safety problems caused by temperature increases.

The explosion-proof valve 4 is arranged on the end cover 3. The explosion-proof valve 4 may include a valve body 5 with a vent hole 6 and a valve cover 7, the valve cover 7 covering the valve body 5 to avoid air leakage.

As shown in fig. 3 and 4, the present utility model provides an explosion-proof apparatus 20 and also provides an end cap 10 and a battery having the explosion-proof apparatus 20. The explosion-proof device 20 can be turned on to timely discharge a large amount of gas generated inside when the battery fails. The gas is typically a flammable gas. Along with the gas discharge, the heat in the battery is diffused outwards, so that the safety problems caused by temperature rise, such as fire, explosion and other safety accidents, can be avoided.

The battery includes a battery case, an end cap 10, and an electrical cell. The battery shell is provided with a containing cavity, and the battery core can be positioned in the containing cavity. The battery case has opposite ends, and an end cap 10 covers at least one end of the battery case. For example, in one embodiment, one end of the battery case is formed with an opening, and the end cap 10 is disposed in the opening of the end of the battery case; in another embodiment, both ends of the battery are formed with openings, and the end caps 10 are respectively disposed in the openings of both ends of the battery case.

As shown in fig. 3 and 4, an explosion-proof device 20 can be provided to the end cap 10. In embodiments where the cell is provided with one end cap 10, the explosion protection means 20 is provided to the end cap 10; in embodiments where the cell is provided with two end caps 10, the explosion proof means 20 is provided to at least one of the two end caps 10. To install the explosion protection device 20, the end cap 10 has an end cap opening 11 therethrough, and the explosion protection device 20 is located within the end cap opening 11 and does not protrude from the end cap 10. Thereby, the explosion-proof device 20 can be fitted into the end cap 10.

The explosion-proof device 20 may include a device body 21 and a snap-fit cover 22, the device body 21 being configured to be disposed at the end cap 10 of the battery. For example, the device body 21 may be provided on the end cap 10 by any suitable means, such as clamping, adhesive, plugging, threaded connection, fastener connection such as screws, and the like. Preferably, the device body 21 is bonded into the end cap port 11, which can overcome space limitations and facilitate battery miniaturization. The device body 21 has a first side and a second side in a first direction parallel to the thickness direction of the end cap 10, specifically, the first side of the device body 21 is a side facing away from the battery cell, and the second side of the device body 21 is a side facing toward the battery cell. The snap-fit cover 22 can be openably and closably connected to the first side of the apparatus body 21 and cover the apparatus body 21. For example, the snap-fit cover 22 may be pivotally connected to the device body 21.

The device body 21 is provided with an exhaust hole 23, and the exhaust hole 23 penetrates the device body 21 in a direction perpendicular to the end cap 10. When a large amount of gas is generated inside the battery due to the failure of the battery, the gas can flow from the gas vent 23 further toward the snap cap 22 when flowing to the end of the battery. The closing cover 22 at the closing position can be pushed by the pressure of the gas to move away from the device main body 21, and at this time, the closing cover 22 is opened to allow the exhaust. The opening of the snap-in cover 22 may also be referred to as the opening of the explosion proof device 20.

The size and shape of the device body 21 is adapted to the size and shape of the end cap 11. For example, the end cap 11 may have a rectangular shape with rounded corners, and the outer peripheral shape of the device body 21 may have a rectangular shape with rounded corners.

In order to solve the problem that a certain time is required for the gas to flow from the inside of the battery cell to the end cap 10, so that the explosion-proof device 20 cannot be opened in time, the explosion-proof device 20 of the present embodiment further includes a phase change material 24, and the phase change material 24 is disposed in the device body 21. The phase change material 24 may be a solid phase change material that is solid at ordinary temperatures. The phase change material 24 is capable of changing from a solid state to a gaseous state upon heating, thereby producing a phase change gas. When the battery fails to generate a large amount of heat, the heat can be quickly transferred to the end cover 10 and the explosion-proof device 20, so that the phase-change material 24 is quickly heated to generate phase change, the phase-change gas is closer to the buckling cover 22, and a part of gas generated in the battery core and the phase-change gas can jointly act on the buckling cover 22, so that the buckling cover 22 is opened, and the explosion-proof device 20 is opened.

The phase change gas generated by the phase change material 24 can increase the gas pressure at the explosion-proof device 20, and is matched with the gas generated inside the battery cell to promote the opening of the explosion-proof device 20. The assistance of the phase change gas can accelerate the explosion-proof device 20 to reach the gas pressure required for opening, so that the explosion-proof device 20 can quickly react to open the exhaust when the battery fails. The explosion phenomenon at the local high temperature part in the middle of the battery cell can be effectively avoided, so that the explosion of the battery cell is avoided, and the safety of the battery is greatly improved.

And the phase change material 24 can absorb heat in the phase change process, so that the temperature of the battery cell is reduced, the explosion of the battery cell is further avoided, and the safety of the battery is higher.

The solid phase change material sublimates in a temperature range of 80 to 300 ℃, and the sublimation temperature is, for example, 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 140 ℃, 160 ℃, 180 ℃, 200 ℃, 220 ℃, 240 ℃, 260 ℃, 270 ℃, 280 ℃, 290 ℃, 300 ℃, or the like. At sublimation temperatures, solid phase change materials are capable of sublimating from a solid state to a gaseous state. The battery fault can cause the temperature inside the battery cell, especially the middle part of the battery cell, to be generally raised to more than 100 ℃, and the phase change material 24 with the sublimation temperature between 80 ℃ and 300 ℃ is selected, so that the battery fault detection device is more suitable for general faults of the battery. Optionally, the solid phase change material sublimates in a temperature range of 85 ℃ to 220 ℃.

To facilitate rapid formation of more phase change gas upon heating, the solid phase change material may be configured as particles that are packed within a covering having a gas permeable structure. The ventilation structure may for example comprise ventilation holes. The use of the cladding not only facilitates the assembly of the phase change material 24, but also prevents the battery cell from being contaminated by the phase change material 24, affecting the battery performance.

Phase change material 24 may include a solid state hydrofluoroether. The solid hydrofluoroether is capable of sublimating to a gaseous state when the temperature reaches above 200 ℃. When the temperature inside the battery cell rises and is transferred to the end cover 10 and the explosion-proof device 20, the solid hydrofluoroether is quickly sublimated from the solid state to the gas state, so that the gas pressure at the explosion-proof device 20 is increased, the explosion-proof device 20 is promoted to reach the opened gas pressure, the exhaust is opened, and the explosion of the battery cell is avoided. Of course, the phase change material 24 may also include other solid phase change materials having sublimation temperatures of 120 ℃ or greater.

As shown in fig. 5, the device body 21 is provided with a mounting hole 25, and the phase change material 24 is disposed in the mounting hole 25, specifically, a clad member filled with a solid phase change material is disposed in the mounting hole 25. Through the spacing of mounting hole 25, can make phase change material 24 keep in device main part 21 steadily, simple structure, assembly efficiency is high to space utilization has been promoted. The mounting hole 25 is open at least at a first side facing away from the cell. The phase change gas generated by the phase change material 24 is able to escape from the aperture of the mounting hole 25 at the first side.

In one embodiment, as in the illustrated embodiment, the mounting holes 25 are open on both the first and second sides, i.e., the mounting holes 25 are through holes. As shown in fig. 5, the explosion-proof device 20 further includes a seal 26, the seal 26 being disposed on the second side and sealing the mounting hole 25. The seal 26 may be adhered to the second side of the device body 21, and may be formed of any suitable material such as a sealing film. Alternatively, the mounting hole 25 may be a blind hole closed at the second side. The blind hole is integrally formed with the device body 21. Specifically, the device body 21 is perforated to form a blind hole integrally formed with the device body 21 when the explosion-proof device is manufactured. The mounting hole 25 is not communicated with the space where the battery cell is located at the second side, so that the battery cell is prevented from being polluted by the phase change material 24, and the battery performance is prevented from being influenced.

The exhaust hole 23 has a first projection area S1 on the plane of the end cover 10, and the phase change material 24 has a second projection area S2, s2= (20% -25%) S1 on the plane of the end cover 10. For example, S2 is 20% S1, 21% S1, 22% S1, 23% S1, 24% S1, 25% S1, and the like. The second projection area S2 is within this range, and the phase change gas can be made to more effectively promote the opening of the explosion-proof apparatus 20. Further, the second projected area of the phase change material 24 may also refer to the projected area of the mounting hole 25 on the plane of the end cap 10.

The number of the exhaust holes 23 may be more than two, for example, two, three, four, five, etc., and the number of the exhaust holes 23 may be set based on the size of the battery and the size of the end cap 10. Thus, the first projected area indicates the total projected area of the two or more exhaust holes 23. More than two vents 23 can be provided around the phase change material 24. That is, the phase change material 24 is disposed between the two or more exhaust holes 23, and accordingly, the mounting hole 25 is also disposed between the two or more exhaust holes 23.

The phase change material 24 is centrally disposed in the device body 21 in a second direction perpendicular to the thickness direction of the end cap 10. The phase change material 24 is arranged in the middle, so that the gas pressure born by the buckling cover 22 under the assistance of phase change gas can be balanced, and the buckling cover 22 can be opened quickly. For the illustrated embodiment, the end cap 10 is rectangular, and the phase change material 24 is centrally disposed in the device body 21 in a second direction parallel to the length direction of the end cap 10; and the phase change material 24 is centrally disposed in the device body 21 in a second direction parallel to the width direction of the end cap 10. That is, the second direction may be the length direction and the width direction of the end cap 10. Of course, the location of the phase change material 24 is not limited and may not be centered, such as around more than two vents. And the phase change material 24 may be disposed at different positions of the device body 21 in a dispersed manner.

According to the present utility model, the explosion-proof device 20 can be accelerated to reach the gas pressure required for opening by the aid of the phase-change gas, so that the explosion-proof device 20 can quickly react to open the exhaust when the battery fails. And the phase change material 24 can absorb heat in the phase change process, so that the temperature of the battery cell is accelerated. From this can effectively avoid the local high temperature department in electric core middle part to appear bursting phenomenon to avoid electric core explosion, reach the explosion-proof effect of pressure release, improved the security of battery greatly.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model pertains. The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the utility model. Features described herein in one embodiment may be applied to another embodiment alone or in combination with other features unless the features are not applicable or otherwise indicated in the other embodiment.

The present utility model has been described by way of the above embodiments, but it should be understood that the above embodiments are for illustrative and explanatory purposes only and that the utility model is not limited to the above embodiments, but is capable of numerous variations and modifications in accordance with the teachings of the utility model, all of which fall within the scope of the utility model as claimed.

Claims (13)

1. An explosion-proof device for a battery, the explosion-proof device comprising:

a device body configured to be disposed at an end cap of the battery;

a snap-fit cover that can be opened and closed, the snap-fit cover covering the device body; and

the phase change material is used for changing into a gaseous state after being heated, the phase change material is arranged in the device main body, and the phase change material is a solid phase change material which is solid at normal temperature.

2. The explosion-proof apparatus according to claim 1, wherein the solid phase change material sublimates in a temperature range of 80 ℃ to 300 ℃.

3. The explosion-proof device according to claim 1, wherein the solid phase change material is configured as particles, the particles being packed in a covering having a gas-permeable structure.

4. The explosion-proof device of claim 1, wherein the phase change material comprises a solid state hydrofluoroether.

5. The explosion-proof device according to any one of claims 1 to 4, wherein the device body is provided with a mounting hole, the phase change material being provided in the mounting hole.

6. The explosion-proof device according to claim 5, wherein the device main body has a first side and a second side in a first direction parallel to a thickness direction of the end cap, the snap cap is openably and closably connected to the first side of the device main body, and the mounting hole is opened at least at the first side.

7. An explosion-proof device according to claim 6, wherein,

the mounting hole is open at the first side and the second side, and the explosion-proof device further comprises a sealing element which is arranged at the second side and seals the mounting hole; or alternatively

The mounting hole is a blind hole closed at the second side.

8. The explosion-proof device according to any one of claims 1 to 4, wherein the device body is provided with a vent hole penetrating the device body in a direction perpendicular to the end cap, the vent hole having a first projected area S1 on a plane in which the end cap lies, the phase change material having a second projected area S2, s2= (20% -25%) S1 on a plane in which the end cap lies.

9. The explosion-proof apparatus according to claim 8, wherein the number of the vent holes is two or more, and two or more of the vent holes are provided around the phase change material.

10. The explosion-proof device according to any one of claims 1 to 4, wherein the phase change material is provided centrally to the device body in a second direction perpendicular to a thickness direction of the end cap.

11. An end cap for a battery, characterized in that the end cap is provided with an explosion proof device according to any one of claims 1 to 10, which is embedded in the end cap.

12. The end cap of claim 11, wherein the end cap has an end cap opening, at least a device body of the explosion proof device being located within the end cap opening and not protruding from the end cap.

13. A battery, the battery comprising:

a battery case formed with a cavity;

an end cap covering to at least one end of the battery case;

the battery cell is positioned in the containing cavity; and

the explosion proof device of any one of claims 1 to 10, disposed on and embedded in the end cap.