CN217134589U - Pressure relief mechanism, end cover, battery monomer, battery and power consumption device - Google Patents

Abstract

The utility model relates to a pressure release mechanism, end cover, battery monomer, battery and power consumption device, including pressure release main part and at least a set of pressure release group, seted up at least one trompil in the pressure release main part, every pressure release group of group covers and locates on every trompil, and every pressure release group of group outward flange and current cover keep sealed the setting between the trompil of establishing. Wherein each pressure relief set is configured to change its volume under the influence of gas vented through the aperture. Through setting up the pressure release group, increase self volume when pressure release mechanism does not satisfy the pressure release condition but trompil discharge excess gas to increase battery inner volume alleviates battery internal pressure, makes each aspect performance such as battery inside atmospheric pressure can not receive the influence, guarantees that the battery stable performance. Compared with alloy materials, the battery with the pressure relief group has small internal pressure increment and has beneficial effect on the performance of the battery under the condition of the same gas production.

Description

Pressure relief mechanism, end cover, battery monomer, battery and power consumption device

Technical Field

The application relates to the technical field of batteries, in particular to a pressure relief mechanism, an end cover, a single battery, a battery and an electric device.

Background

Energy conservation and emission reduction are the key points of sustainable development of the automobile industry, and electric vehicles become important components of the sustainable development of the automobile industry due to the advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in its development.

In the prior art, in order to improve the safety performance of the battery, a pressure relief mechanism is arranged on a shell of the battery. The pressure relief mechanism is generally made of alloy materials, and a pressure relief channel is formed when the internal pressure of the battery is high to relieve the pressure of the battery so as to reduce the pressure difference between the inside and the outside of the battery and further reduce the probability of thermal failure of the battery.

However, when excessive gas (e.g., high-temperature gas) is generated inside the battery case but the internal pressure of the battery case does not satisfy the opening condition of the pressure relief mechanism, the pressure relief mechanism does not perform any pressure relief operation, and the overheated gas may cause the internal pressure of the battery to increase, thereby affecting the performance of the battery before the pressure relief mechanism is opened.

SUMMERY OF THE UTILITY MODEL

Based on the above problem, the application provides a pressure release mechanism, end cover, battery monomer, battery and power consumption device, can alleviate before pressure release mechanism opens, and the inside gas production of battery leads to the problem that battery internal pressure risees excessively.

In a first aspect, the application provides a pressure relief mechanism, including pressure relief main part and at least one set of pressure relief group, seted up at least one trompil in the pressure relief main part, every pressure relief group of group covers and locates on every trompil, and the outward flange of every pressure relief group of group and current cover keep sealed setting between the trompil of establishing. Wherein each pressure relief set is configured to change its volume under the influence of gas vented through the aperture.

So, through setting up the pressure release group, increase self volume when pressure release mechanism does not satisfy the pressure release condition but trompil discharge excess gas to increase battery internal volume alleviates battery internal pressure, makes each aspect performance such as battery internal pressure can not receive the influence, guarantees that the battery stable performance. Compared with an alloy material pressure relief mechanism, the battery with the pressure relief set has small internal pressure increment and has beneficial effect on the performance of the battery when the same gas production rate is achieved.

In some embodiments, each pressure relief set includes a first pressure relief member capable of deforming and changing its volume under the action of gas vented through the opening. So, through setting up the first pressure release spare that can produce the deformation, alleviate battery internal pressure increment before pressure release mechanism opens pressure release channel, avoid battery internal pressure too big to cause the influence to the battery performance.

In some embodiments, each pressure relief group comprises at least one second pressure relief member, all the second pressure relief members are stacked along the gas discharging direction in the opening and cover the opening where the second pressure relief member is located, and the first pressure relief member is arranged on the topmost layer of all the second pressure relief members.

In some embodiments, each second pressure relief element is capable of forming an exhaust path for the gas to exit when exposed to temperatures above its melting point and/or pressures above its limiting pressure.

Through establish the second pressure release piece on the basis upper strata of first pressure release piece for the second pressure release piece can carry out primary treatment, carries out primary protection to first pressure release piece. And through the stack of establishing of second pressure release piece, can make the volume that the pressure release group increases under the gas effect of trompil exhalant bigger to hold more gas volume and then balanced battery inside atmospheric pressure.

In some embodiments, the first and/or second pressure relief members are formed by one or more layers of flexible material that are laminated to ensure that the pressure relief assembly can change shape or state with the environment and impact force to increase or decrease its volume.

In some embodiments, the pressure relief body is made of a rigid material, and the pressure relief set is formed by laminating a plurality of layers of soft films. So as to ensure that the pressure relief main body has certain strength and corrosion resistance and can also deform under set conditions. The pressure relief group is a multi-layer soft adhesive film to ensure that the softness of the pressure relief group is kept under repeated deformation.

In some embodiments, the thickness of the first pressure relief member is in the range of 0.3mm to 5mm to avoid a situation where the first pressure relief member is too thin to rupture prematurely during deformation, or a situation where the first pressure relief member is too thick to relieve pressure.

In some embodiments, the amount of deformation of the first pressure relief increases as the thickness of the first pressure relief increases. In practical application, the thickness of the first pressure relief piece can be reasonably set according to the capacity of the battery and the requirement on the thermal reaction control speed of the battery, so that the internal pressure of the battery can be quickly adjusted.

In some embodiments, the pressure relief body further comprises a weak portion recessed in a thickness direction of the pressure relief body, the weak portion being configured as a second pressure relief opening of the pressure relief body. Through the setting of local weak part, can guarantee the structural strength of pressure release main part, can realize quick open valve when it satisfies the valve opening condition simultaneously again.

In some embodiments, the pressure relief body and the first pressure relief member are in a bonded or snap-fit connection to ensure that a seal is maintained between the outer edge of the pressure relief body and the currently covered opening.

In a second aspect, the present application provides an end cap comprising a top cover sheet and the pressure relief mechanism of the above embodiments, wherein the pressure relief mechanism is disposed on the top cover sheet.

In a third aspect, the present application provides a battery cell, which includes a housing having an opening at one end thereof and an end cap covering the opening of the housing in the above embodiment.

In a fourth aspect, the present application provides a battery including the battery cell of the above embodiment.

In a fifth aspect, the present application provides an electric device, which comprises the battery in the above embodiments, wherein the battery is used for providing electric energy.

Above-mentioned pressure release mechanism can be applied to the battery field and be used for carrying out the pressure release to the battery. Specifically, a pressure relief main body and pressure relief groups are arranged, holes are formed in the pressure relief main body, and each pressure relief group is arranged on each hole in a covering mode. When the pressure release group received the effect by the trompil combustion gas, the pressure release group can change self volume under this gaseous effect to increase self volume when pressure release mechanism did not satisfy the pressure release condition but the inside excessive gas that produces of battery, with increase battery internal volume, alleviate battery internal pressure, make all aspects performances such as the inside atmospheric pressure of battery can not receive the influence, guarantee battery stable performance.

Drawings

Various additional advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Moreover, like reference numerals are used to refer to like elements throughout. In the drawings:

FIG. 1 is a schematic illustration of a vehicle according to an embodiment of the present application;

fig. 2 is an exploded view of a battery according to an embodiment of the present application;

fig. 3 is an exploded view of a battery cell according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of a pressure relief mechanism according to an embodiment of the present disclosure;

FIG. 5 is a schematic view of a pressure relief mechanism according to another embodiment of the present application;

FIG. 6 is a schematic view of a pressure relief mechanism according to another embodiment of the present application;

FIG. 7 is a schematic view of a pressure relief mechanism according to another embodiment of the present application;

fig. 8 is a graph of gas production inside a battery versus pressure increase inside the battery for different first pressure relief member materials in another embodiment of the present application.

Reference numerals:

1000. a vehicle; 100. a battery; 200. a controller; 300. a motor; 10. a box body; 11. a first portion; 12. a second portion; 20. a battery cell; 21. an end cap; 22. a housing; 23. an electrode assembly; 25. a pressure relief mechanism; 251. a pressure relief body; 2511. a weakened portion; 252. a pressure relief group; 2521. a first pressure relief member.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are merely used to more clearly illustrate the technical solutions of the present application, and therefore are only examples, and the protection scope of the present application is not limited thereby.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first", "second", and the like are used only for distinguishing different objects, and are not to be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary-secondary relationship of the technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is only one kind of association relationship describing an associated object, and means that three relationships may exist, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural pieces" refers to two or more (including two).

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the directions or positional relationships indicated in the drawings, and are only for convenience of description of the embodiments of the present application and for simplicity of description, but do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are used in a broad sense, and for example, may be fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

At present, the application of the power battery is more and more extensive from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles and electric automobiles, and a plurality of fields such as military equipment and aerospace. With the continuous expansion of the application field of the power battery, the market demand is also continuously expanding.

The applicant notices that along with the continuous expansion of the application field of the battery, the safety of the battery becomes more important, when the battery monomer is out of control due to heat, high temperature and high pressure are discharged from the battery monomer, and at the moment, high temperature and high pressure gas breaks through the pressure relief mechanism, so that the pressure relief mechanism can discharge the high temperature and high pressure gas.

The lithium cell mainly adopts modes such as nick on the metal as the pressure release mechanism of lithium cell, and the inside gas expansion of battery, pressure increase are the trace desolder constantly to certain degree when the battery heaies up, and the pressure release of gassing to avoid the battery explosion, improve the security performance of lithium cell. The pressure relief mechanism has a large starting pressure value for releasing gas and relieving pressure, and if a large amount of gas is generated in the battery shell but the pressure does not meet the valve opening condition of the pressure relief mechanism, the gas cannot be released and the pressure relief is carried out, so that the internal gas pressure and various performances of the battery are negatively influenced, and the performance of the battery is influenced.

In order to alleviate the influence of the excessive gas generated in the battery before the pressure relief mechanism is opened on the internal pressure of the battery, the applicant researches and discovers that when the excessive gas generated in the battery shell does not meet the pressure relief condition of the pressure relief mechanism, the volume in the battery can be properly increased by arranging a corresponding structure so as to accommodate the generated excessive gas, so that the pressure change in the battery shell is avoided, and the internal structure of the battery is protected.

The pressure relief mechanism may be provided with a corresponding area structure capable of adjusting the volume of the battery when the battery is in different states, and when a large amount of gas is generated in the battery case, the area structure may change itself to easily accommodate the gas and increase the volume of the battery.

Based on the above consideration, in order to alleviate the influence of a large amount of gas generated inside the battery on the internal pressure of the battery before the pressure relief mechanism is opened, the applicant has conducted intensive research to design a pressure relief mechanism, in which two different pressure relief mechanisms are formed by a structure, wherein the volume of the pressure relief mechanism itself is variable, so that the volume inside the battery is increased when excessive gas is generated inside the battery.

Can use the pressure release mechanism that this application embodiment disclosed, locate on the free end cover of battery. The battery cell manufactured by the pressure relief mechanism disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but not limited to the electric devices. Can use and possess this power system with electric installation of constitution such as battery monomer, battery that this application discloses, like this, be favorable to alleviating pressure release mechanism before opening, the problem of the influence battery performance that the battery is inside overheated or the pressure is too high to promote battery performance and battery life.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be but is not limited to a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, and the like, and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, and the like.

For convenience of description, the following embodiments take an example in which a power consuming apparatus according to an embodiment of the present application is a vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present disclosure. The vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or a range-extended automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

In some embodiments of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure. The battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a receiving space for the battery cells 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 cover each other, and the first portion 11 and the second portion 12 together define a receiving space for receiving the battery cell 20. The second part 12 may be a hollow structure with one open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and second portions 11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100, the number of the battery cells 20 may be multiple, and the multiple battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the multiple battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 100 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery module, and then connecting a plurality of battery modules in series, in parallel, or in series-parallel to form a whole, and the whole is accommodated in the box 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but is not limited to, a lithium sulfur battery, a sodium ion battery, or a magnesium ion battery. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shape.

Referring to fig. 3, fig. 3 is an exploded schematic view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery. As shown in fig. 3, the battery cell 20 includes an end cap 21, a case 22, an electrode assembly 23, and other functional components.

The end cap 21 refers to a member that covers an opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 22 to fit the housing 22. Alternatively, the end cap 21 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 21 is not easily deformed when being impacted, and the battery cell 20 may have a higher structural strength and improved safety. The end cap 21 may be provided with functional components such as electrode terminals. The electrode terminals may be used to electrically connect with the electrode assembly 23 for outputting or inputting electric energy of the battery cell 20. In some embodiments, the end cap 21 may further include a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value, i.e., the pressure relief mechanism mentioned in the above description. The material of the end cap 21 may also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate the electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The case 22 is an assembly for mating with the end cap 21 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to house the electrode assembly 23, electrolyte, and other components. The housing 22 and the end cap 21 may be separate components, and an opening may be formed in the housing 22, and the opening may be covered by the end cap 21 to form the internal environment of the battery cell 20. Without limitation, the end cap 21 and the housing 22 may be integrated, and specifically, the end cap 21 and the housing 22 may form a common connecting surface before other components are inserted into the housing, and when it is necessary to enclose the inside of the housing 22, the end cap 21 covers the housing 22. The housing 22 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 22 may be determined according to the specific shape and size of the electrode assembly 23. The material of the housing 22 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in the embodiments of the present invention.

The electrode assembly 23 is a part in which electrochemical reactions occur in the battery cell 20. One or more electrode assemblies 23 may be contained within the case 22. The electrode assembly 23 is mainly formed by winding or stacking an anode sheet and a cathode sheet, and a separator is generally provided between the anode sheet and the cathode sheet. The portions of the anode and cathode plates having active materials constitute the main body of the electrode assembly, and the portions of the anode and cathode plates having no active materials constitute tabs, respectively. The anode tab and the cathode tab may be located at one end of the main body portion together or at both ends of the main body portion, respectively. During the charge and discharge of the battery, the anode active material and the cathode active material react with the electrolyte, and the tabs are connected with the electrode terminals to form a current loop.

According to some embodiments of the present disclosure, referring to fig. 4 to 7, the pressure relief mechanism 25 provided in the present disclosure includes a pressure relief body 251 and at least one pressure relief group 252, the pressure relief body 251 is provided with at least one opening, each pressure relief group 252 is disposed on each opening, and an outer edge of each pressure relief group 252 and the currently disposed opening are sealed. Wherein each pressure relief set 252 is configured to change its volume under the influence of gas vented through the openings.

The pressure relief body 251 is generally configured to be a sheet, and may be in any shape or made of any material, and serves as a mounting base of the pressure relief group 252, for fixing the pressure relief group 252 on the end cap 21, and the pressure relief body 251 and the pressure relief group 252 may serve as a pressure relief channel of the pressure relief mechanism 25, which will be described in detail below.

The pressure relief group 252 may have a single-layer or multi-layer structure, an outer edge of the pressure relief group 252 is an outermost portion of the pressure relief group 252 relative to the pressure relief body 251, and the outermost portion may be hermetically connected to any position of the pressure relief body 251 or to an aperture wall of the opening where the pressure relief group is located, so that a communication channel for gas cannot be formed between the outer edge of the pressure relief group 252 and the opening, and it is ensured that all gas exhausted from the pressure relief group 252 acts on the pressure relief group 252 to change its own volume.

It can be understood that the pressure relief body 251 needs to have certain rigidity and can effectively support the outer edge of the pressure relief set 252 when the pressure relief set 252 changes its volume, so as to ensure that the gas exhausted from the pressure relief set 252 is completely contained in its volume.

For example, when a large amount of superheated gas or high-temperature gas is generated inside the battery 100, the superheated gas or the high-temperature gas impacts the pressure relief set 252 through the opening to increase the volume of the pressure relief set, so as to relieve the pressure change caused by the superheated gas or the high-temperature gas inside the battery 100, thereby avoiding the influence of the superheated gas or the high-temperature gas on the performance of the internal pressure of the battery 100 before the pressure relief mechanism 25 relieves the pressure.

So, through setting up pressure release group 252, increase self volume when pressure release mechanism 25 does not satisfy the pressure release condition but trompil discharge excess gas to increase battery 100 internal volume, alleviate battery 100 internal pressure, make each aspect performance such as battery 100 internal pressure can not receive the influence, guarantee battery 100 stable performance. Compared with alloy materials, the battery 100 provided with the pressure relief set 252 has small pressure increment inside the battery 100 at the same gas production rate, and has beneficial effects on the performance of the battery 100.

According to some embodiments of the present application, each set of pressure relief sets 252 optionally includes a first pressure relief member 2521, and the first pressure relief member 2521 can deform and change its volume under the action of the gas exhausted from the openings.

The first pressure relief element 2521 can be deformed, and the material thereof needs to be made of a flexible material, and when the first pressure relief element 2521 is deformed under the action of the gas discharged from the opening, the space formed inside the first pressure relief element 2521 is the volume of the first pressure relief element itself, so that the first pressure relief element is superposed with the volume of the housing 22 in the cell 100 to increase the internal volume of the cell 100.

For example, referring to fig. 2 and fig. 6 to fig. 7, the first pressure relief element 2521 of the pressure relief mechanism 25 is shown from before deformation to after deformation, when the pressure relief mechanism 25 is in the state shown in fig. 6, the first pressure relief element 2521 is impacted by the gas inside the battery 100, the gas is exhausted through the opening and impacts on the first pressure relief element 2521, and the first pressure relief element 2521 is driven to protrude towards the side away from the inside of the battery 100, so as to form the hemispherical convex shape in fig. 7, where the hemispherical structure inside is the self volume of the pressure relief set 252.

Referring to fig. 2 to 4 and further referring to fig. 8, a relationship diagram of the gas production rate inside the battery 100 and the internal pressure of the battery 100 is provided, D1 is the deformable first pressure relief element 2521 provided by the present application, D2 is made of a conventional alloy material, and the abscissa is the gas production rate inside the battery 100 and the ordinate is the internal pressure of the battery 100.

It can be seen that, compared to the alloy material, when the gas production rate inside the battery 100 is the same, i.e., the abscissa is the same, the increase of the pressure inside the battery 100 equipped with the first pressure relief member 2521 is small, i.e., the ordinate is relatively small, thereby alleviating the increase of the pressure inside the battery 100.

Thus, by providing the first pressure relief element 2521 capable of deforming, the increase in the internal pressure of the battery 100 is relieved before the pressure relief mechanism 25 opens the pressure relief channel, thereby avoiding the influence on the performance of the battery 100 caused by the excessive internal pressure of the battery 100.

Optionally, according to some embodiments of the present application, the deformation of the first pressure relief 2521 is an elastic deformation.

Elastic deformation refers to the change of the relative position between points caused by the action of external force, and when the external force is removed, the solid is restored to its original shape, which is called elastic deformation. First pressure relief member 2521 is deformed by the internal gas of battery 100, and after the deformation occurs, the increase in internal pressure of battery 100 is relieved. If the inside of the battery 100 returns to normal, the gas expansion force disappears, and the first pressure relief member 2521 can also return to the original shape.

Thus, the first pressure relief element 2521 can be automatically adjusted according to different states, and the internal performance of the battery 100 is kept stable. When the gas inside the battery 100 is discharged through the opening, the battery is deformed, and when no gas is normally discharged through the opening inside the battery 100, the battery returns to a non-deformed state.

According to some embodiments of the present application, each set of pressure relief groups 252 optionally includes at least one second pressure relief member, all of which are stacked in the direction of air discharge from the openings and cover the openings where they are located, and the first pressure relief member 2521 is disposed at the topmost layer of all of the second pressure relief members.

The second pressure relief piece may be made of a material having the same structure and material as the first pressure relief piece 2521, or a material having a different structure and material, and the second pressure relief piece located at the bottommost layer among the plurality of second pressure relief pieces is covered on the opening where the second pressure relief piece is currently located, and the outer edge of the second pressure relief piece and the currently covered opening are sealed.

According to some embodiments of the present application, each second pressure relief element is optionally capable of forming an exhaust channel (not shown) for gas to exhaust when exposed to a temperature above its melting point and/or a pressure above its limiting pressure.

The melting point is the temperature at which the solid changes (melts) the state of the solid from solid to liquid, when the second pressure relief piece is impacted by high-temperature gas, the temperature brought by the high-temperature gas is higher than the melting point temperature of the second pressure relief piece, the second pressure relief piece generates state change, and the solid is changed into the liquid to form an exhaust channel.

The ultimate pressure is the highest pressure that the system or device can achieve under normal operating conditions. When the second pressure relief piece is impacted by high-pressure gas, the pressure brought by the high-pressure gas is greater than the limit pressure which can be borne by the second pressure relief piece, and the second pressure relief piece is cracked, holed or changed in other forms to form an exhaust channel.

It is understood that, when the condition for forming the vent passage is satisfied by one of the second vents located at the lowermost layer of all the second vents, the vent passage is communicated between the opening and the remaining second vents of the upper layer to allow the gas to be discharged. When any one of the second pressure relief members located in the middle layers of all the second pressure relief members meets the condition for forming the exhaust passage, the exhaust passage is communicated between the opening and the second pressure relief member located in the upper layer for exhausting gas. When the second pressure relief members located at the top layer of all the second pressure relief members satisfy the condition of forming the exhaust passage, the exhaust passage is communicated between the first pressure relief member 2521 and the opening for exhausting the gas.

When the first pressure relief element 2521 is stacked, the projection of the first pressure relief element 2521 facing the second pressure relief element needs to cover at least part of the second pressure relief element attached to the second pressure relief element, so that after the exhaust passage is formed, the gas can be smoothly exhausted into the first pressure relief element 2521 and the volume of the gas can be changed. The other part of the second pressure relief part, which does not form the exhaust passage, can be deformed simultaneously with the first pressure relief element 2521 to increase the upper limit of the increased volume of the pressure relief set 252 under the action of the gas exhausted from the opening.

In this way, the second pressure relief element is layered on the first pressure relief element 2521, so that the second pressure relief element can be disposed once to protect the first pressure relief element 2521 once. And through the overlapping of the second pressure relief member, the adjustable range of the increased volume of the pressure relief group 252 under the action of the gas exhausted from the opening is larger, so as to accommodate more gas quantity and further balance the internal gas pressure of the battery 100.

It is understood that the melting point and the ultimate pressure of the second pressure relief element are set to be as small as possible to avoid that the gas inside the battery 100 cannot form a gas exhaust channel for exhausting the gas when the gas is too much.

According to some embodiments of the present application, optionally, the first pressure relief element 2521 has a predetermined melting point, and when the first pressure relief element 2521 is at a temperature higher than the predetermined melting point, the first pressure relief element 2521 forms a first pressure relief opening communicating with the outside.

This application produces deformation in order to alleviate battery 100 internal pressure through setting up first pressure release 2521, if battery 100 is inside to produce gas excessively or pressure lasts to rise to being greater than second utmost point voltage limiting force this moment, then first pressure release 2521 can't the original state, can produce the change of fracture, trompil or other forms to produce first pressure release opening, open the valve pressure release fast.

When the first pressure relief element 2521 is impacted by the gas exhausted from the opening, all the second pressure relief elements have been broken to form a gas channel, and the first pressure relief element 2521 is deformed to increase the volume thereof. When the temperature of the first pressure relief element 2521 is higher than the predetermined melting point, the temperature inside the battery 100 is too high, and in order to avoid explosion of the battery 100, the first pressure relief element 2521 generates a state change, and is changed from a solid state to a liquid state to generate a first pressure relief opening, so that the pressure relief mechanism 25 opens the valve to relieve pressure.

The outside is an atmospheric environment, and under normal conditions, the internal temperature of the battery 100 is equal to the atmospheric environment, and when the internal temperature of the battery 100 is too high, the internal temperature of the battery 100 needs to be reduced by pressure relief through the first pressure relief opening, so that the battery 100 is ensured not to generate further safety accidents.

Thus, with the above arrangement, when the temperature inside the battery 100 is too high, and the increase of the volume of the pressure relief set 252 itself cannot be controlled, the valve is opened to release the pressure to the outside, so as to ensure the safety of the battery 100.

According to some embodiments of the present application, optionally, the first pressure relief element 2521 has a first limit pressure, and when the first pressure relief element 2521 is located at a pressure higher than the first limit pressure, the first pressure relief element 2521 forms a first pressure relief opening communicating with the outside.

The first limit pressure is the highest pressure that the system or device can achieve under normal operating conditions. This application produces deformation increase self volume in order to alleviate battery 100 internal pressure through setting up first pressure release 2521, if battery 100 is inside to be produced gas too much or pressure continuously risees to being greater than first ultimate pressure this moment, and first pressure release 2521 can't the original state, can produce the change of fracture, trompil or other forms to produce first pressure release opening, carry out relief mechanism 25's the pressure release of opening the valve.

When the first pressure relief element 2521 is impacted by the gas exhausted from the opening, all the second pressure relief elements have been broken to form a gas channel, and the first pressure relief element 2521 is deformed to increase its volume. When the pressure of the first pressure relief element 2521 is higher than the first limit pressure, the internal pressure of the battery 100 is too high to be out of control at this time, and in order to avoid explosion of the battery 100, the first pressure relief element 2521 serves as a pressure relief channel of the pressure relief mechanism 25, and is opened to relieve pressure.

Thus, with the above arrangement, when the internal pressure of the battery 100 is too high, and the increase of the volume of the pressure relief set 252 itself cannot be controlled, the valve is opened to relieve the pressure, so as to ensure the safety of the battery 100.

Moreover, the preset melting point and the first limit pressure form a double insurance of the pressure relief mechanism 25, and when any parameter of the temperature and/or the pressure inside the battery 100 is greatly abnormal, the pressure relief mechanism 25 can be opened quickly to relieve the pressure, so that the safety of the battery 100 is improved.

It can be understood that, when the first pressure relief element 2521 is deformed to increase its volume, the bulging volume of the first pressure relief element 2521 may reflect the internal pressure of the battery 100 in real time, the greater the bulging of the first pressure relief element 2521, the greater the internal pressure of the battery 100, and when the first pressure relief element 2521 is not deformed, the normal internal pressure of the battery 100 is indicated, so that the internal pressure of the battery 100 is monitored in real time through a simple structure, and in this scheme, the abnormal change of the internal pressure can be known without placing a pressure sensor inside the battery 100.

Referring to fig. 2 to 4 and further to fig. 8, it can be seen that, under the same limit pressure (i.e., P2 value in the figure), the first pressure relief element 2521 provided by the present application can bear a gas production rate generated inside the battery 100 that is greater than that of a conventional alloy material, so that before the pressure relief mechanism 25 opens the valve to relieve the pressure, if the gas is abnormally produced inside the battery 100, the first pressure relief element 2521 provided by the present application can effectively control the internal pressure of the battery 100, thereby ensuring the stability of the internal performance of the battery 100.

According to some embodiments of the present application, optionally, the first pressure relief 2521 and/or the second pressure relief are formed by one or more layers of a flexible material laminate.

The flexible material is a material with softness and flexibility, and can be a material which is stressed to stretch, bend, twist and deform without losing performance, or a material which is heated to melt, and also can have the two characteristics.

In this way, the first pressure relief element 2521 and/or the second pressure relief element are formed by laminating flexible materials, so as to ensure that the pressure relief set 252 can change its shape or state according to the environment and the impact force applied thereto, so as to perform the operation of increasing its volume or opening the first pressure relief opening as described in the above embodiments.

According to some embodiments of the present application, optionally, the pressure relief body 251 is made of a rigid material, and the pressure relief group 252 is formed by laminating a plurality of layers of soft films.

Rigid material, as used herein, refers to a material having a certain structural strength and corrosion resistance relative to the flexible material, which is capable of undergoing an unrecoverable deformation, such as a local rupture, under a sufficiently high pressure or a sufficiently high temperature. The pressure relief body 251 is preferably made of a metal sheet, which is a thin sheet structure made of metal and may be circular, square or any other shape, and the metal material is preferably an aluminum alloy, so as to ensure that the pressure relief body 251 has certain strength and corrosion resistance and can deform under a set condition.

The soft rubber film is made of one of polyvinyl chloride, polyvinyl alcohol, rubber or thermoplastic polyurethane rubber, and elements such as F (fluorine), Cl (chlorine), S (sulfur), Pb (lead) and the like are added to increase the strength and corrosion resistance of the soft rubber film, so that the softness of the soft rubber film under repeated deformation is maintained.

Alternatively, in one embodiment, the pressure relief assembly 252 includes a first pressure relief member 2521 formed by stacking one or more layers of flexible films, wherein the predetermined melting point of the first pressure relief member is 150 ° to 180 °, and the flexible films melt to open the first pressure relief opening when the internal temperature of the battery 100 is within this range.

Further, in the pressure relief pack 252 configuration with a second relief member, the melting point and ultimate pressure of the second relief member is less than the melting point and ultimate pressure of the first relief member 2521.

According to some embodiments of the present application, optionally, the first pressure relief 2521 has a thickness in the range of 0.3mm to 5 mm.

The thickness range defined in the above embodiments includes the total thickness range of the first pressure relief element 2521 during the deformation and the non-deformation, and it can be understood that, when the first pressure relief element 2521 is deformed to increase its volume, its thickness decreases gradually to approach 0.3 mm.

Further, the thickness of the first pressure relief element 2521 when not deformed ranges from 2mm to 5mm, so as to avoid the situation that the first pressure relief element 2521 is too thin and is broken in advance during the deformation process, or the situation that the first pressure relief element 2521 cannot be relieved due to too thick first pressure relief element 2521.

Within this thickness range, when the pressure relief mechanism provided by the present application is used in a lithium iron phosphate battery, the ultimate pressure (i.e., P2) that the pressure relief set 252 can withstand is in the range of 0.4MPa to 0.8MPa, and when the pressure relief mechanism provided by the present application is used in a lithium ternary battery, the ultimate pressure that the pressure relief set 252 can withstand is in the range of 0.75MPa to 1.05 MPa. It will be appreciated that the particular ultimate pressure is also related to other performance parameters of the battery being used.

According to some embodiments of the present application, optionally, the amount of deformation of first relief 2521 increases with increasing thickness of first relief 2521.

Specifically, the protrusion generated by the deformation of the first pressure relief element 2521 is approximately regarded as a circumference, and measured in a certain amount relationship as r = x/β, where r is the circumferential radius generated by the deformation of the first pressure relief element 2521, x is the thickness of the first pressure relief element 2521, and β is the coefficient of material of the pressure relief body 251, and is a certain value. As the first pressure relief member 2521 is thicker, the circumferential radius generated by deformation thereof is larger, so that the first pressure relief member 2521 can accommodate more gas production of the battery 100.

As such, the thicker the first pressure relief element 2521, the stronger the durability thereof, the greater the deformation amount of the first pressure relief element 2521, and the material and structural strength of the first pressure relief element 2521 itself also affect the first limit pressure.

Further, as shown, the relationship between the internal pressure of the battery 100 and the thickness of the first pressure relief element 2521 provided herein is of an amount:

；

wherein, the bulge generated by the deformation of the first pressure relief element 2521 is approximately regarded as a circumference, p1 is the internal pressure of the battery 100, v ₁ Is the battery 100 in a normal stateInternal volume, T is temperature, n is the amount of material of the gas, and R is the molar gas constant.

It is understood that as x becomes larger, the radius r of the circumference generated by the deformation of the first relief 2521 becomes larger and p decreases. In this way, the increase in the thickness of the first pressure relief element 2521 can effectively control the increase rate of the internal pressure of the battery 100.

In practical application, the thickness of the first pressure relief element 2521 can be reasonably set according to the capacity of the battery 100 and the requirement on the thermal response control speed of the battery 100, so that the internal pressure of the battery 100 can be rapidly adjusted. According to some embodiments of the present application, optionally, the pressure relief body 251 has a second limit pressure, when the pressure relief body 251 is under a pressure higher than the second limit pressure, the pressure relief body 251 forms a second pressure relief opening, and the first limit pressure is smaller than the second limit pressure.

That is, the pressure relief body 251 itself may also be used as a pressure relief channel of the pressure relief mechanism 25, and if the first pressure relief element 2521 is failed, fatigue, or other abnormal conditions, which causes the internal pressure of the battery 100 to exceed the first limit pressure but the first pressure relief opening is not opened, the pressure relief body 251 serves as a dual protection, and opens the second pressure relief opening to realize the valve opening pressure relief of the pressure relief mechanism 25.

The second pressure relief opening can be opened by the pressure relief body 251 itself to be cracked, holed, or other changes, which is not limited herein.

So, through setting up second pressure release opening, realize duplicate protection together with first pressure release opening, can also realize the pressure release through pressure release main part 251 when first pressure release 2521 is out of order for pressure release mechanism 25's pressure release effect is better, and battery 100's security is higher.

It can be understood that the pressure relief mechanism 25 provided in the present application has three pressure relief valve opening conditions:

(1) when the internal temperature of battery 100 is higher than the predetermined melting point, first pressure relief element 2521 melts to open the first pressure relief opening;

(2) when the internal pressure of battery 100 is higher than the first limit pressure, first pressure relief element 2521 is ruptured to open the first pressure relief opening;

(3) first pressure relief element 2521 fails, the internal pressure of battery 100 is higher than the second limit pressure, and pressure relief body 251 ruptures to open the second pressure relief opening.

According to some embodiments of the present application, optionally, the pressure relief body 251 further includes a weak portion 2511, the weak portion 2511 is concavely provided to the pressure relief body 251 in a thickness direction of the pressure relief body 251, and the weak portion 2511 is configured as a second pressure relief opening of the pressure relief body 251.

The weak portion 2511 is recessed, which means that the thickness of the weak portion 2511 is smaller than the thickness of the other portions of the pressure relief body 251 in the thickness direction of the pressure relief body 251, and if the internal pressure of the battery 100 is greater than the second limit pressure at this time, the pressure relief body 251 is first broken from the weak portion 2511, thereby forming a second pressure relief opening.

As described above, the local weak portion 2511 can provide a quick valve opening when the pressure relief body 251 satisfies the valve opening condition while ensuring the structural strength.

According to some embodiments of the present application, optionally, the pressure relief body 251 and the first pressure relief element 2521 are in a sticking connection or a snap-fit connection.

By adhering, it is meant that the first pressure relief element 2521 is attached to the pressure relief body 251 by adhesive, wherein the adhesive may be adhesive tape, glue, etc.

The pressure relief body 251 is sleeved on the periphery of the first pressure relief element 2521.

It should be noted that, in the above two connection manners, it is necessary to ensure that the outer edge of the pressure relief main body 251 and the currently covered opening are kept in a sealing arrangement, so as to avoid air leakage from the gap position where the two are connected, and further disable the pressure regulation function of the pressure relief group 252.

In other embodiments, the pressure relief body 251 and the first pressure relief element 2521 may be connected in other suitable manners, which are not limited herein.

According to some embodiments of the present application, there is also provided an end cap 21, comprising a top cover sheet and the pressure relief mechanism 25 described in any of the above aspects, so as to form a pressure relief channel of the battery 100 on the end cap 21.

According to some embodiments of the present application, there is also provided a battery cell 20 including a housing 22 having an opening at one end and an end cap 21 covering the opening of the housing 22.

According to some embodiments of the present application, there is also provided a battery 100 including the battery cell 20 according to the above aspects.

According to some embodiments of the present application, there is also provided an electric device, including the battery 100 according to the above aspects, wherein the battery 100 is used for providing electric energy.

According to some embodiments of the present application, referring to fig. 4 to 7, the present application provides a pressure relief mechanism 25, wherein the pressure relief body 251 is a metal sheet and is disposed in a two-sided waist-shaped circumference, and a square opening is opened in the center of the pressure relief body. The pressure relief set 252 is a first pressure relief member 2521 formed of a soft plastic film and attached to the square opening. The pressure relief body 251 has a weak portion 2511, and the weak portion 2511 surrounds the outer circumference of the first pressure relief member 2521 to configure a second pressure relief opening of the pressure relief body 251. When gas is generated inside the battery 100, the first pressure relief member 2521 is deformed to one side and protrudes, thereby increasing the gas inside the battery 100 to relieve the pressure inside the battery 100, so as to protect the battery 100. When the internal temperature of the battery 100 is higher than the preset melting point temperature or the pressure is higher than the first limit pressure, the soft adhesive film is melted or broken to generate a first pressure relief opening, and when the internal pressure of the battery 100 is higher than the second limit pressure, a second pressure relief opening is generated. Thereby protecting the internal performance of the battery 100 before the valve opening of the pressure release mechanism 25 and realizing rapid pressure release after the valve opening condition is satisfied.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (14)

1. A pressure relief mechanism, comprising:

the pressure relief main body is provided with at least one opening;

each group of pressure relief groups covers each opening, and the outer edge of each group of pressure relief groups and the currently covered opening are sealed;

wherein each of said pressure relief groups is configured to change its volume under the influence of gas vented from said aperture.

2. The pressure relief mechanism of claim 1 wherein each of said pressure relief sets includes a first pressure relief member capable of deforming and changing its volume under the action of gas vented through said opening.

3. The pressure relief mechanism according to claim 2, wherein each of said pressure relief groups includes at least one second pressure relief member, all of said second pressure relief members being stacked in a direction of gas discharge from said openings and overlapping said opening where said first pressure relief member is currently located, said first pressure relief member being provided at a topmost layer of all of said second pressure relief members.

4. The pressure relief mechanism of claim 3, wherein each of said second pressure relief elements is capable of forming an exhaust path for the gas to exit when exposed to temperatures above its melting point and/or pressures above its limiting pressure.

5. The pressure relief mechanism of claim 3, wherein the first pressure relief member and/or each second pressure relief member is formed from one or more layers of a flexible material laminate.

6. The pressure relief mechanism of claim 5 wherein said pressure relief body is made of a rigid material and said pressure relief assembly is formed by laminating a plurality of layers of flexible films.

7. The pressure relief mechanism of claim 2, wherein the first pressure relief member has a thickness in a range of 0.3mm to 5 mm.

8. The pressure relief mechanism of claim 7, wherein the amount of deformation of the first pressure relief member increases as the thickness of the first pressure relief member increases.

9. The pressure relief mechanism of claim 1 wherein said pressure relief body further comprises a weakened portion recessed in said pressure relief body along a thickness direction of said pressure relief body;

the weak portion is configured as a second pressure relief opening of the pressure relief body.

10. The pressure relief mechanism of claim 1 wherein said pressure relief body is adhesively or snap-fit attached to the outer edge of each said pressure relief set.

11. An end closure comprising a top closure flap and a pressure relief mechanism as claimed in any of claims 1 to 10, said pressure relief mechanism being provided on said top closure flap.

12. A battery cell, comprising: a housing having an opening at one end and the end cap of claim 11 covering the opening of the housing.

13. A battery comprising the cell of claim 12.

14. An electrical device comprising the battery of claim 13, wherein the battery is configured to provide electrical energy.

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