CN218586253U - Battery cell, battery and power consumption device - Google Patents

Abstract

The application discloses battery monomer, battery and electric installation, this battery monomer include shell and insulating part, are equipped with pressure release mechanism on the shell, and the insulating part covers on one side that the shell is kept away from to pressure release mechanism, is equipped with a plurality of weak portions on the insulating part, and the distance between two adjacent weak portions in a plurality of weak portions is L, and wherein, 2mm is less than or equal to L and is less than or equal to 6mm. The insulating part is installed on the shell and covers the outer side of the pressure relief mechanism, and the insulating part is used for shielding the pressure relief mechanism. The interval distance between two adjacent weak portions is set in the [2mm,6mm ] interval, so that the structure of the insulating part has certain strength, the conditions that the processing weak portions and the insulating part are broken when the insulating part is used are reduced, when the single battery is out of control due to heat, when the pressure reaches the opening pressure of the pressure relief mechanism, the pressure relief mechanism is broken by high-temperature substances, the weak portions are broken, the insulating part is broken at the weak portions, normal opening of the pressure relief mechanism is achieved, and safety risks are reduced.

Description

Battery cell, battery and power consumption device

Technical Field

The application relates to the technical field of batteries, in particular to a battery monomer, a battery and an electric device.

Background

This section provides background information related to the present disclosure only and is not necessarily prior art.

With the development of new energy, new energy is adopted as power in more and more fields. The secondary battery has the advantages of high energy density, cyclic charging, safety, environmental protection and the like, so that the secondary battery is widely applied to the fields of new energy automobiles, consumer electronics, energy storage systems and the like.

In the structural design of a secondary battery, in order to improve the safety performance of the battery, a pressure relief mechanism is usually added on an end cover of a battery cell, and the battery is relieved by the pressure relief mechanism when the battery is in an abnormal state and is out of control due to heat. An insulator is typically attached to the end cap to protect the cells. The insulating part forms the shelter from pressure release mechanism, has blockked pressure release mechanism's normal opening and pressure release, has increased battery safety risk.

SUMMERY OF THE UTILITY MODEL

In view of above-mentioned problem, this application provides a battery monomer, battery and power consumption device, can guarantee the normal opening of pressure release mechanism, reduces the safety risk.

A first aspect of the present application provides a battery cell, including:

the shell is provided with a pressure relief mechanism;

the insulation piece covers one side, far away from the shell, of the pressure relief mechanism, a plurality of weak portions are arranged on the insulation piece, the distance between every two adjacent weak portions in the weak portions is L, and L is larger than or equal to 2mm and smaller than or equal to 6mm.

According to the battery monomer of this application, wherein, the insulating part is installed on the shell and is covered in pressure relief mechanism's the outside, utilizes the insulating part to shelter from pressure relief mechanism formation. When the distance between two adjacent weak portions is smaller than 2mm, the strength of the insulating part is weaker, the weak portions and the insulating part are easy to break when being processed, when the distance between two adjacent weak portions is larger than 6mm, the strength of the insulating part is larger, impact force generated on the insulating part when the pressure relief mechanism is opened cannot effectively guarantee that the insulating part at the weak portions is broken, and the pressure relief mechanism is easy to cause that pressure cannot be relieved smoothly. The interval distance between two adjacent weak parts is set in the interval of [2mm,6mm ], so that the structure of the insulating part has certain strength, the condition that the insulating part is broken when the weak parts are machined and the insulating part is used is reduced, meanwhile, when the single battery is out of control due to heat, the internal pressure inside the shell is increased, when the pressure reaches the opening pressure of the pressure relief mechanism, the high-temperature substance breaks through the pressure relief mechanism and breaks the insulating part, the insulating part is broken at the weak parts, the normal pressure relief of the pressure relief mechanism is realized, and the safety risk is reduced.

In some embodiments of the present application, the plurality of weak portions are provided in correspondence with the pressure relief mechanism. The pressure relief mechanism and the weak part are correspondingly arranged, so that the weak part is more easily broken in the process of opening the pressure relief mechanism for pressure relief, and the safety risk is further reduced.

In some embodiments of the present application, the plurality of weak portions are disposed at equal intervals. Through setting all weak parts to equidistant setting for the structural strength of weak part department insulating part is even, has guaranteed the fracture effect of the in-process insulating part that is broken away at pressure release mechanism, has avoided insulating part to produce to open pressure release mechanism to block to a certain extent, makes pressure release mechanism's opening operation go on smoothly.

In some embodiments of the present application, the weak portion is a through hole or a concave structure.

The through hole is formed in the weak portion, so that the strength of the insulating part located in the weak portion is effectively reduced, the insulating part can be broken at the position of the weak portion by small impact force when the pressure relief mechanism is opened, the insulating part is prevented from shielding the pressure relief mechanism to a certain extent, and smooth opening of the pressure relief mechanism is achieved.

The weak part is arranged into a concave structure, so that the adverse effect of external environmental factors on the pressure relief mechanism through the weak part is reduced.

In some embodiments of the present application, a pressure relief hole for installing the pressure relief mechanism is provided on the housing, and a projection of the pressure relief hole on the insulating member falls into an area surrounded by the plurality of weak portions.

Set the projection of pressure release hole at the insulating part to fall into the regional of a plurality of weak parts encircleing in, the regional pressure release hole that covers completely that a plurality of weak parts enclose, when battery monomer takes place thermal runaway, the free discharge of battery makes the regional other regional backs that break away from the insulating part that a plurality of weak parts enclose, and remaining insulating part can not shelter from the pressure release hole, has consequently reduced the influence of insulating part to the free pressure release of battery.

In some embodiments of the present application, the shortest distance between the plurality of weaknesses and the projected edge is D, where D ∈ [0mm,5mm ]. The distance between the weak part and the edge of the projection of the pressure relief hole on the insulating part is set to be [0mm,5mm ], so that the manufacturing difficulty of the insulating part is reduced while the normal opening of the pressure relief mechanism is ensured, and the processing efficiency of the insulating part is improved.

In some embodiments of the present application, the plurality of weak portions are formed in a shape of a straight line, a zigzag, a curved line, a cross, an X, a circle, an ellipse, or a Chinese character mi.

The shape of all the weak parts formed on the insulating part is set to be in a straight line shape, a broken line shape, a curve shape, a cross shape, an X shape, a circle shape, an oval shape or a rice shape, so that the diversity of the weak parts is improved, and the weak parts can meet the requirements of normal opening of different pressure relief mechanisms.

In some embodiments of the present application, a single said weakened portion is rectangular in shape, said rectangle having a width M, wherein M ∈ [0.5mm,2mm ]; and/or the length of the rectangle is N, wherein N belongs to [4mm,8mm ]. The shape of the weak part is set to be rectangular, so that the processing is convenient and fast, and the processing efficiency can be effectively improved. In addition, the weak part is rectangular, the width of the rectangle is set within the range of [0.5mm,2mm ], on the basis of ensuring the normal opening of the pressure relief mechanism, the insulating part is effectively ensured to have good structural strength, and the condition of fracture in the processing or using process is avoided to a certain extent. The single weak part is rectangular, the length of the rectangle is set within the interval of [4mm,8mm ], so that the weak part can be effectively broken in the opening process of the pressure relief mechanism by controlling the width of the weak part, the strength of the insulating part can be ensured, and the problems that the normal opening of the pressure relief mechanism is influenced due to the small length of the weak part and the structural strength of the insulating part is influenced due to the large length of the weak part are avoided to a certain extent.

In some embodiments of the present application, the insulation is one of a mica piece, a ceramic piece, and a fiberglass piece;

or the insulating part is a composite part formed by at least two of the mica part, the ceramic part and the glass fiber part.

Through setting up the insulating part into one of mica spare, ceramic member and glass fiber spare, perhaps set up the insulating part into the composite member of two kind at least formations in mica spare, ceramic member and the glass fiber spare, not only can improve the intensity of insulating part, also can make insulating part self have the heat-proof quality simultaneously, avoided external environment to a certain extent to the influence of pressure relief mechanism production badness.

A second aspect of the present application proposes a battery including: a battery cell as described above.

A third aspect of the present application proposes an electric device comprising a battery or a battery cell as described above, the battery or the battery cell being configured to provide electrical energy.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

Drawings

Fig. 1 schematically shows a structural schematic diagram of a vehicle according to an embodiment of the present application;

fig. 2 schematically shows a structural view of a battery pack according to an embodiment of the present application;

fig. 3 schematically shows a structural view of a battery module according to an embodiment of the present application;

fig. 4 is a schematic exploded view schematically showing a partial structure of a battery cell according to an embodiment of the present application (an insulating member is a first embodiment);

fig. 5 is a schematic structural view of an insulating member of the battery cell shown in fig. 4;

fig. 6 is a partial structural view of the battery cell shown in fig. 4 (the insulating member is not shown);

FIG. 7 is a schematic view of the insulator shown in FIG. 5 from another perspective;

FIG. 8 is an enlarged view of the portion A of the insulator shown in FIG. 7;

fig. 9 schematically shows a structural view of an insulating member according to an embodiment of the present application in a second embodiment;

fig. 10 schematically shows a structural view of an insulating member according to an embodiment of the present application in a third embodiment.

The reference numbers are as follows:

1000 is a vehicle;

100 is a battery, 200 is a controller, and 300 is a motor;

110 is a battery module, 120 is a box body, 121 is a first part, and 122 is a second part;

1 is a battery monomer;

10 is a shell;

20 is an end cover;

21 is a pressure relief hole;

30 is an electrode terminal;

40 is a pressure relief mechanism;

50 is an insulating part;

the reference numeral 51 denotes a weak portion, and 52 denotes a projection.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present application more clearly, and therefore are only used as 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 figures above, 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.

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 specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning 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, electric automobiles and the like, 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 the design of the pressure relief mechanism is added on the end cover of the battery cell, and the pressure of the battery is relieved through the pressure relief mechanism when the battery is in an abnormal state and is out of control due to heat. An insulator is typically attached to the end cap to protect the cells. The insulating part has formed sheltering from pressure release mechanism, has blockked the normal opening and the pressure release of pressure release mechanism, has increased battery safety risk, therefore how to realize the problem of the normal opening of pressure release mechanism of thermal runaway battery becomes the technical problem that technical staff in the field need to solve urgently.

In order to solve the problem of normal opening of a pressure relief mechanism of a thermal runaway battery, the applicant researches and discovers that when thermal runaway of a battery monomer occurs, the internal pressure inside a shell is increased by arranging a plurality of weak parts on an insulating member covering the outer side of the pressure relief mechanism and arranging the spacing distance between two adjacent weak parts in a range of [2mm,6mm ], and when the pressure reaches the opening pressure of the pressure relief mechanism, a high-temperature substance breaks the pressure relief mechanism and breaks the weak parts, so that the insulating member is effectively broken at the weak parts to realize normal opening and pressure relief of the pressure relief mechanism, and the safety risk is reduced.

The battery cell disclosed in the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but not limited thereto. A power supply system including the electric device composed of the battery cell, the battery, and the like disclosed in the present application may be used.

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, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to be applied to the above-described battery and electric equipment, but may be applied to all batteries including a box and electric equipment using the battery.

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 power requirements for operation during starting, navigation, and traveling of the vehicle 1000.

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.

In order to meet different power requirements, the battery 100 may include a plurality of battery cells 1, and the battery cell 1 refers to a minimum unit constituting the battery module 110 or the battery pack. A plurality of battery cells 1 may be connected in series and/or in parallel via the electrode terminals 30 to be applied to various applications. The battery 100 referred to in the present application includes a battery module 110 or a battery pack. The plurality of battery cells 1 may be connected in series, in parallel, or in series-parallel, where series-parallel refers to a mixture of series connection and parallel connection. The battery 100 may also be referred to as a battery pack. In the embodiment of the application, the plurality of battery cells 1 may directly form the battery pack, or the battery module 110 may be formed first, and then the battery module 110 forms the battery pack.

Fig. 2 shows a schematic structural diagram of the battery 100 according to an embodiment of the present application. In fig. 2, the battery 100 may include a plurality of battery modules 110 and a case 120, and the plurality of battery modules 110 are received inside the case 120. The case 120 is used to accommodate the battery cells 111 or the battery module 110 to prevent liquid or other foreign substances from affecting the charge or discharge of the battery cells 111. The box body 120 may be a single cuboid, a cylinder, a sphere, or other simple three-dimensional structure, or may be a complex three-dimensional structure formed by combining cuboid, cylinder, or sphere, which is not limited in the embodiment of the present application. The material of the box 120 may be an alloy material such as an aluminum alloy and an iron alloy, a polymer material such as polycarbonate and polyisocyanurate foam, or a composite material such as glass fiber and epoxy resin, which is not limited in the embodiment of the present application.

In some embodiments, the case 120 may include a first portion 121 and a second portion 122, the first portion 121 and the second portion 122 cover each other, and the first portion 121 and the second portion 122 together define a space for accommodating the battery cell 1. The second part 122 may be a hollow structure with an open end, the first part 121 may be a plate-shaped structure, and the first part 121 covers the open side of the second part 122, so that the first part 121 and the second part 122 jointly define a space for accommodating the battery cell 1; the first portion 121 and the second portion 122 may be both hollow structures with one side open, and the open side of the first portion 121 is covered on the open side of the second portion 122.

Fig. 3 shows a schematic structural diagram of the battery module 110 according to an embodiment of the present application. In fig. 3, the battery module 110 may include a plurality of battery cells 1, the plurality of battery cells 1 may be connected in series or in parallel or in series-parallel to form the battery module 110, and the plurality of battery modules 110 may be connected in series or in parallel or in series-parallel to form the battery 100. In the present application, the battery cell 1 may include a lithium ion battery 100, a sodium ion battery 100, a magnesium ion battery 100, or the like, which is not limited in the embodiments of the present application. The battery cell 1 may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells 1 are generally divided into three types in an encapsulated manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are not limited in the embodiment of the application. However, for the sake of brevity, the following embodiments are all described by taking a square battery cell as an example.

Fig. 4 is an exploded schematic view of a battery cell 1 according to some embodiments of the present disclosure. The battery cell 1 refers to the smallest unit constituting the battery 100. As shown in fig. 4, the battery cell 1 includes an end cap 20, a case, an electrode terminal 30, a pressure relief mechanism 40, and an insulator 50.

The housing includes an end cap 20 and a case 10.

The end cap 20 refers to a member that covers the opening of the case 10 to insulate the internal environment of the battery cell 1 from the external environment. Without limitation, the shape of the end cap 20 may be adapted to the shape of the housing 10 to fit the housing 10. Alternatively, the end cap 20 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 20 is not easily deformed when being extruded and collided, and the single battery 1 may have a higher structural strength and improved safety performance.

As shown in fig. 4 and 6, the case 10 is an assembly for fitting the end cap 20 to form an internal environment of the battery cell 1, wherein the formed internal environment can be used for accommodating a cell assembly (the cell assembly is a component in which electrochemical reaction occurs in the battery cell, one or more cell assemblies can be contained in the case 10. The cell assembly is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally disposed between the positive electrode sheet and the negative electrode sheet. The housing 10 and the end cap 20 may be separate components, and an opening may be formed in the housing 10, and the opening may be covered by the end cap 20 to form the internal environment of the battery cell 1. Without limitation, the end cap 20 and the housing 10 may be integrated, and specifically, the end cap 20 and the housing 10 may form a common connecting surface before other components are inserted into the housing, and when it is required to enclose the inside of the housing 10, the end cap 20 covers the housing 10. The housing 10 may be of various shapes and various sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, and the like. Specifically, the shape of the housing 10 may be determined according to the specific shape and size of the electric core assembly 113. The material of the housing 10 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment.

In the embodiment of the present application, the case 10 and the end cap 20 are independent components, and the case of the battery cell 1 is formed by assembling the two components as an example:

as shown in fig. 4 and 6, the electrode terminals 113 are disposed on the top of the end cap 20. The electrode terminal 30 may be used to electrically connect with the electric core assembly inside the battery cell 1 for outputting or inputting electric power of the battery cell. During the charge and discharge of the battery 100, the positive and negative active materials react with the electrolyte, and the tabs are connected to the electrode terminals 30 to form a current loop.

As shown in fig. 6, the pressure relief mechanism 40 is disposed on the end cap 20, when the internal pressure or temperature of the single battery 1 reaches a threshold value, the pressure inside the single battery will force the pressure relief mechanism 40 away, and the internal substance will be released from the position of the pressure relief mechanism 40, so as to implement the pressure relief of the single battery 1, thereby reducing the problems of explosion and the like of the single battery 1. Further, the pressure relief mechanism 40 may be a structure formed on the end cap 20 (for example, the end cap is thinned, and the thinned position is punched away by increasing the internal pressure to implement the pressure relief operation), and an independent component mounted on the end cap 20 is also provided, specifically, in this application, the end cap 20 is provided with the pressure relief hole 21, the pressure relief mechanism 40 is the pressure relief mechanism 40 (the pressure relief mechanism 40 may be a metal material, or may be a flame-retardant polymer material such as polyvinyl chloride, polyvinylidene chloride, and fluoroplastic), and is mounted on the pressure relief hole 21 to seal the pressure relief hole 21, the pressure relief mechanism 40 is a plate-shaped member, and a corresponding weakening structure (for example, a notch structure or the like) is provided on the plate-shaped member, when thermal runaway occurs in the battery cell 1, a high-temperature and high-pressure substance (gas and/or solid) is formed in the battery cell 1, after the high-temperature and high-pressure substance reaches a certain pressure, the weakening structure may be broken, and the high-position high-pressure substance may be ejected through the broken position, thereby implementing the pressure relief on the battery cell 1, and reducing the explosion of the battery cell 1.

As shown in fig. 5, the insulating member 50 is mounted on the top surface of the end cap 20, the insulating member 50 covers the pressure relief mechanism 40, the insulating member 50 is an insulating member (which may also have thermal insulation performance), the pressure relief mechanism 40 is protected by the insulating member 50, and impact of external thermal diffusion substances on the pressure relief mechanism 40 is reduced, so as to ensure safety of the battery cell 1.

In some embodiments of the present application, as shown in fig. 4 and 8, a battery cell 1 is provided, where the battery cell 1 includes a housing and an insulating member 50, the housing is provided with a pressure relief mechanism, the insulating member covers a side of the pressure relief mechanism away from an inside of the housing, the insulating member is provided with a plurality of weak portions 51, and a distance between two adjacent weak portions 51 in the plurality of weak portions 51 is L, where L is greater than or equal to 2mm and less than or equal to 6mm.

Specifically, the insulator 50 is mounted on the housing and covers the outside of the pressure relief mechanism 40, and the insulator 50 shields the pressure relief mechanism 40. When the distance between two adjacent weak portions 51 is less than 2mm, the strength of the insulating member 50 is weak, the weak portions 51 and the insulating member 50 are easy to break when being processed, and when the distance between two adjacent weak portions 51 is greater than 6mm, the strength of the insulating member 50 is large, so that impact force generated on the insulating member 50 when the pressure relief mechanism 40 is opened cannot effectively guarantee that the insulating member 50 at the weak portions 51 is broken, and the pressure relief mechanism 40 is easy to cause that the pressure relief mechanism 40 cannot smoothly relieve pressure.

In the application, the interval distance between two adjacent weak parts 51 is set in the interval of [2mm,6mm ], so that the structure of the insulating part 50 has certain strength, the fracture condition of the insulating part when the weak parts 51 and the insulating part 50 are processed is reduced, meanwhile, when the battery cell 1 is out of thermal runaway, the internal pressure inside the shell is increased, when the pressure reaches the opening pressure of the pressure relief mechanism 40, a high-temperature substance breaks the pressure relief mechanism 40 and breaks the insulating part, so that the insulating part 50 is effectively fractured at the position of the weak part 51, the normal pressure relief of the pressure relief mechanism 40 is realized, and the safety risk is reduced.

It should be understood that when the pressure relief mechanism 40 is opened, the insulating member 50 at the weak portion 51 is broken by the impact force to form a channel for ejecting the high-temperature and high-pressure substance in the battery cell 1, thereby ensuring the normal opening of the pressure relief mechanism 40.

It should be noted that, the end cap 20 of the battery cell 1 is located at the top of the battery cell 1, when the insulating member 50 is installed at the top of the battery cell 1, the insulating member 50 is connected and fixed with the end cap 20, and after the insulating member 50 is connected and fixed with the end cap 20, the projection of the pressure relief mechanism 40 located on the end cap 20 on the insulating member 50 is located on the insulating member 50, that is, the insulating member 50 can completely cover the pressure relief mechanism 40, so as to ensure the shielding effect of the insulating member 50 on the pressure relief mechanism 40.

In the embodiment of the present application, the distance between two adjacent weak portions 51 may be set to 2mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, or 6.0mm.

In some embodiments of the present application, a plurality of weaknesses 51 are provided in correspondence with the pressure relief mechanism 40.

Specifically, the plurality of weak portions 51 are provided in correspondence with the pressure relief mechanism 40, which means that, in the thickness direction of the insulator 50, a projection of the plurality of weak portions 51 or an area surrounded by the plurality of weak portions 51 on the housing at least partially covers the pressure relief mechanism 40.

When thermal runaway occurs in the single battery 1, the pressure inside the housing increases and reaches the opening pressure of the pressure relief mechanism 40, and then the pressure relief mechanism 40 is opened, so that high-temperature substances inside the housing are released. Through corresponding the setting with pressure relief mechanism 40 and weak part 51, pressure relief mechanism 40 is opening the back, and the high temperature material is more easily broken the weak part 51 of insulating part 50 to realize the quick discharge of high temperature material, make the safety risk obtain reducing.

In some embodiments of the present application, as shown in fig. 5 and 7, the plurality of weak portions 51 are provided at equal intervals.

Specifically, the weak portions 51 are formed on the insulating member 50, and all the weak portions 51 are set to be disposed at equal intervals on the insulating member 50, so that the structural strength of the insulating member 50 at the weak portions 51 is uniform, thereby ensuring the fracture effect of the insulating member 50 in the opening process of the pressure relief mechanism 40, further avoiding the blocking of the insulating member 50 against the normal opening of the pressure relief mechanism 40 to a certain extent, and enabling the opening action of the pressure relief mechanism 40 to be smoothly performed.

It should be noted that the plurality of weakened portions 51 are arranged at equal intervals, which means that the distances between any two adjacent weakened portions 51 are equal, and the plurality of weakened portions 51 are arranged at equal intervals, so that the weakened portions 51 can be conveniently machined in the manufacturing process, the convenience of machining is improved, and the manufacturing cost is reduced.

In addition, the plurality of weak portions 51 are arranged at equal intervals, so that the strength of all the weak portions 51 is uniform and stable, the breaking uniformity of the pressure relief mechanism 40 in the valve opening process is ensured, and the condition that the normal opening of the pressure relief mechanism 40 is influenced due to the fact that the local weak portions 51 are not broken is avoided to a certain extent.

In other embodiments of the present application, all the weakened portions 51 may be provided at equal intervals, may be provided at unequal intervals, or the like.

In some embodiments of the present application, the distance L =4mm between two adjacent weak portions 51.

Specifically, the plurality of weak portions 51 are formed on the insulating member 50, and the adjacent two weak portions 51 are arranged at equal intervals, when the distance between the adjacent two weak portions 51 is small, the impact force required for breaking the position of the weak portion 51 is small during the opening of the pressure relief mechanism 40, and when the distance between the adjacent two weak portions 51 is large, the impact force required for breaking the position of the weak portion 51 is large during the opening of the pressure relief mechanism 40, so how to select the distance between the adjacent two weak portions 51 is an important criterion for balancing the normally-opened state of the pressure relief mechanism 40 and the good structural strength of the insulating member 50.

Through design and repeated verification, the distance between two adjacent weak parts 51 is set to be 4mm, so that the insulating part 50 can be effectively broken at the weak parts 51 by the generated impact force in the opening process of the pressure relief mechanism 40, the insulating part 50 has good structural strength, and the condition that the insulating part 50 is broken in the processing or using process is reduced.

It should be noted that, in the present application, the distance between two adjacent weak portions 51 is 4mm, and for the current general battery cell 1, when the structure of the battery cell 1 changes, the distance between two adjacent weak portions 51 can be adaptively adjusted according to the distance structure of the battery cell 1 and the pressure relief mechanism 40, here, the present application is not repeated for the adjusted data, although the present application does not describe the distance between two adjacent weak portions 51 in detail, it should also be understood as belonging to the protection scope of the present application.

In some embodiments of the present application, the weak portion 51 is a through-hole or a recess structure formed on the insulating member.

In some implementation processes of the embodiment, the weak portion 51 is set to be a through hole, so that the strength of the insulating piece 50 located at the position of the weak portion 51 is effectively reduced, and further, when the pressure relief mechanism 40 is opened, the insulating piece 50 can be broken at the position of the weak portion 51 by a small impact force, so that shielding of the pressure relief mechanism 40 is avoided to a certain extent, and smooth opening of the pressure relief mechanism 40 is realized.

It should be noted that the through holes are formed in the insulating member 50 by stamping, which improves the convenience of processing and reduces the manufacturing cost of the insulating member 50.

In some implementations of the present embodiment, the weak portion 51 is configured as a concave structure, so that when the insulating member 50 is broken at the position of the weak portion 51, opposite sides of the insulating member 50 are prevented from penetrating, and adverse effects of external environmental factors on the pressure relief mechanism 40 through the weak portion 51 are reduced.

Note that the recessed structure is a structure formed by locally removing material in the thickness direction of the insulating member 50, and the thickness of the insulating member 50 at the position of the recessed structure is smaller than the thickness of the insulating member 50 at other positions (regions outside the recessed structure). This sunk structure accessible laser engraving mode such as processes, through setting weak part 51 to sunk structure, has avoided pressure relief mechanism 40 and external isolation to a certain extent, and then has reduced pressure relief mechanism 40 and has received the influence of external harmful factor.

In some embodiments of the present application, as shown in fig. 5 and 7, the housing is provided with a pressure relief hole 21 for installing the pressure relief mechanism 40, and the projection 52 of the pressure relief hole 21 on the insulating member 50 falls into an area surrounded by the plurality of weak portions 51.

When thermal runaway occurs in the battery cell 1, the pressure relief mechanism 40 of the housing needs to be opened due to increase of internal pressure, impact force generated in the opening process impacts the insulating member 50, and the insulating member 50 is broken at the position of the weak portion 51, so that the pressure relief mechanism 40 is prevented from being normally opened.

When the thermal runaway of the battery cell 1 occurs, after the area surrounded by the plurality of weak portions 51 is separated from other areas of the insulating member 50 by the discharge of the battery cell 1, the residual insulating member 50 does not shield the pressure relief hole 21, so that the influence of the insulating member 50 on the pressure relief of the battery cell 1 is reduced.

In addition, when the weak portion 51 is a through hole, the weak portion 51 needs to be disposed outside the projection 52 of the pressure relief mechanism 40 on the insulating member 50, so that the explosion of the pressure relief mechanism 40 caused by the external adverse factor (high-temperature substance sprayed by other thermal runaway battery cells 1) reaching the position of the pressure relief mechanism 40 through the through hole structure is reduced, the thermal diffusion phenomenon of the chain reaction is avoided to a certain extent, and the use safety of the battery 100 is ensured.

In some embodiments of the present application, as shown in fig. 7, the edge of the region surrounded by the plurality of weak portions 51 is disposed at equal intervals from the edge of the projection 52.

Specifically, when thermal runaway occurs in the battery cell 1, the pressure relief mechanism 40 is opened and impacts the insulating member 50, the insulating member 50 is broken at the position of the weak portion 51, a channel for spraying out high-temperature substances is formed, because the projection 52 is formed on the insulating member 50 by the pressure relief mechanism 40, the projection 52 of the pressure relief hole 21 on the insulating member 50 falls into an area surrounded by the weak portions 51, and the edge of the area surrounded by the weak portions 51 is arranged at equal intervals with the edge of the projection 52, the shape of the channel is matched with that of the pressure relief hole 21, and is equal to the edge distance of the pressure relief hole 21, so that the situation that the channel is relatively offset relative to the pressure relief hole 21 to block the spraying out of the high-temperature substances is reduced, and the normal opening of the pressure relief mechanism 40 is ensured.

It should be noted that, in the present application, the shape of the plurality of weak portions 51 formed on the insulating member 50 may correspond to the shape of the projection 52 of the pressure relief hole 21 on the insulating member, for example, the projection 52 is a racetrack shape, and the surrounding shape of the plurality of weak portions 51 formed on the insulating member 50 is a racetrack shape (disposed at intervals outside the projection 52); the projection 52 is circular, and the surrounding shape of the plurality of weak portions 51 formed on the insulating member 50 is circular (arranged at intervals outside the projection 52); the projection 52 is rectangular, and the surrounding shape of the plurality of weak portions 51 formed on the insulating member 50 is rectangular (arranged at intervals outside the projection 52), or the like.

In addition, as shown in fig. 7, the plurality of weak portions 51 are disposed outside the projection of the pressure relief hole 21 on the insulating member 50, so that a clearance in the opening process of the pressure relief mechanism 40 is increased, the clamping stagnation phenomenon of the corresponding structure is reduced in the opening process of the pressure relief mechanism 40, and the normal opening operation of the pressure relief mechanism 40 is further ensured.

In some embodiments of the present application, the shortest distance between the plurality of weakenings 51 and the edge of the projection 52 is D, where D e [0mm,5mm ].

Specifically, the weak portion 51 is a rectangular through hole, the plurality of weak portions 51 are arranged around the projection 52 formed on the insulating member 50 of the pressure relief hole 21, the surrounding shape formed by the plurality of weak portions 51 is consistent with the shape of the projection 52, meanwhile, the plurality of weak portions 51 are positioned outside the projection 52 and are arranged at intervals with the edge of the projection 52, and by arranging the plurality of weak portions 51, on the basis of ensuring the normal opening of the pressure relief mechanism 40, the difficulty in the manufacturing process of the weak portions 51 is reduced to a certain extent, and the efficiency in the processing process of the insulating member 50 is improved to a certain extent.

In the embodiment of the present application, the shortest distance D between the weak portion 51 and the edge of the projection 52 may be set to 0mm, 1mm, 1.5mm, 2.0mm, 2.5mm, 3.0mm, 3.5mm, 4.0mm, 4.5mm, or 5.0mm.

In some embodiments of the present application, the shortest distance D =0.5mm between the weak portion 51 and the edge of the projection 52.

When the shortest distance between the plurality of weak portions 51 and the edge of the projection 52 is large, the impact force required in the fracture process of the weak portions 51 is large, and when the shortest distance between the plurality of weak portions 51 and the edge of the projection 52 is small, the impact force required in the fracture process of the weak portions 51 is small, so through design and repeated experimental verification, the shortest distance between the plurality of weak portions 51 and the edge of the projection 52 is set to be 0.5mm, so that the insulation member 50 can be fractured at the position of the weak portion 51 by small pressure in the normal opening process of the pressure relief mechanism 40, and the normal opening of the pressure relief mechanism 40 can be realized. In addition, the manufacturing difficulty of the insulating member 50 is also reduced to a certain extent, so that the processing efficiency of the insulating member 50 is improved to a certain extent.

In some embodiments of the present application, the plurality of weak portions 51 are formed in a shape of a straight line, a zigzag line, a curved line, a cross (as shown in fig. 9), an X (as shown in fig. 10), a circle, an ellipse, or a meter.

Specifically, by setting the preset shape of the plurality of weak portions 51 to a straight shape, a zigzag shape, a curved shape, a cross shape, an X shape, a circular shape, an oval shape, or a rice shape, the diversity of the weak portions 51 is increased, so that the weak portions 51 can be adapted to the requirements of normal opening of different pressure relief mechanisms 40.

It should be understood that the more complicated the shape structure formed by the plurality of weak portions 51 in the projection 52, the lower the strength of the insulating member 50 in the projection 52, and the smaller the impact force required for the insulating member 50 to break at the positions of the plurality of weak portions 51, therefore, the preset shape types formed by the plurality of weak portions 51 in the projection 52 are specifically set according to different requirements, and the detailed description of the specific types of the shapes formed by the plurality of weak portions 51 is omitted in this application.

In some embodiments of the present application, the shape of the single weakened portion 51 is rectangular, circular, triangular or diamond.

Specifically, by providing the shape of the weak portion 51 as a rectangle, a circle, a triangle, or a diamond, the variety of the weak portion 51 is increased, so that the structure formed by the plurality of weak portions 51 can satisfy the requirements for normal opening of different pressure relief mechanisms 40.

In some embodiments of the present application, as shown in FIGS. 5 and 7, the single weakened portion 51 is rectangular in shape, having a width M, where M ∈ [0.5mm,2mm ].

Specifically, providing the shape of the single weak portion 51 in a rectangular shape facilitates the processing and manufacturing of the weak portion 51 in the manufacturing process, so that the efficiency of the processing is improved.

When the width of the rectangle is large, the strength of the insulating piece 50 at the position of the weak part 51 is weak, the impact force required for fracture is small, when the width of the rectangle is small, the strength of the shoe body at the position of the weak part 51 is strong, the impact force required for fracture is large, the width of the rectangular weak part 51 is set within the interval of [0.5mm,2mm ], on the basis of ensuring the normal opening of the pressure relief mechanism 40, the insulating piece 50 is effectively ensured to have good structural strength, and the fracture condition in the processing or using process is avoided to a certain extent.

It should be understood that when the weak portion 51 is a through hole, the larger the width of the weak portion 51 is, the more the end cap 20 is exposed to the outside through the through hole of the insulating member 50, and the external environment is liable to cause adverse effects on the end cap 20 and the structure (the pressure relief mechanism 40, etc.) on the end cap 20 through the through hole.

It should be noted that, in the embodiment of the present application, the width M of the rectangle may be 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.7mm, 1.9mm … … 2.0.0 mm.

In some embodiments of the present application, the single weakened portion 51 is rectangular, having a width M =1.5mm.

Specifically, when the weak portion 51 is rectangular, the width of the rectangular weak portion 51 is set to 1.5mm and the width of the 1.5mm weak portion 51, so that the insulation member 50 can be kept at the best structural strength while the insulation member 50 can be effectively broken during normal opening of the pressure relief mechanism 40, and the situation that the insulation member 50 is broken at the position of the weak portion 51 during processing and use is avoided to a certain extent.

In some embodiments of the present application, as shown in FIG. 7, the single weakened portion 51 is rectangular, having a length N, where N e [4mm,8mm ].

Specifically, the shape of the single weak portion 51 is a rectangle, the width dimension and the length dimension of the rectangle are defined, and when the width of the rectangle is 1.5mm, the rectangular length of the rectangular weak portion 51 is set within a range of [4mm,8mm ], so that the weak portion 51 can be effectively broken during the opening process of the pressure relief mechanism 40 by controlling the width of the weak portion 51, the strength of the insulating member 50 can be ensured, and the problems that the normal opening of the pressure relief mechanism 40 is influenced due to the small length of the weak portion 51, and the structural strength of the insulating member 50 is influenced due to the large length of the weak portion 51 are avoided to a certain extent.

It should be understood that when the weak portion 51 is a through hole, the greater the length of the weak portion 51, the more the end cap 20 is exposed to the outside through the through hole of the insulating member 50, and the external environment is liable to cause adverse effects on the end cap 20 and the structure (the pressure relief mechanism 40, etc.) on the end cap 20 through the through hole.

It should be noted that, the area of the pressure relief hole 21 is determined by the battery cell 1 according to a chemical system, capacity and the like, the length and the width of the weak portion 51 are determined according to the area, the length and the width of the weak portion 51 need to be referred to the length and the width of the electrode assembly, generally, in the width direction, in order to reduce the influence of other factors on the opening pressure of the pressure relief mechanism 40, it is defined that the distance from the edge of the pressure relief hole 21 to the edge of the battery cell 1 is greater than or equal to 4mm in the width direction, and after the width is determined, the length of the pressure relief hole 21 can be calculated according to the area (in an actual situation, the existing pressure relief mechanism 40 is selected according to the size of the battery cell 1, and a large area is selected as much as possible on the basis of space satisfaction).

In the embodiment of the present application, the length N of the rectangle may be 4mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm, 7.0mm, 7.5mm … … 8.0.0 mm.

In some embodiments of the present application, the area of the projection 52 of the pressure relief vent in the insulator 50 is greater than 1000mm ² The length N =7mm of the rectangle.

Specifically, the length of the weak portion 51 which is rectangular is set according to the area of the projection 52 of the pressure relief hole 21 on the insulating member 50, the length of the weak portion 51 is set by comparing the area of the projection 52 with a preset value, and when the area of the projection 52 is larger than the preset value, the length of the rectangle is 7mm, so that the normal opening requirement of the large-size pressure relief mechanism 40 is ensured.

In some embodiments of the present application, the area of the projection 52 of the pressure relief vent in the insulator 50 is less than 1000mm ² The length of the rectangle N =5mm.

Specifically, the length of the rectangular weak portion 51 is set according to the area of the projection 52 of the pressure relief hole 21 on the insulating member 50, and the length of the weak portion 51 is set by comparing the area of the projection 52 with a preset value, and when the projection 52 is smaller than or equal to the preset area, the rectangular length is 5mm, so as to ensure the normal opening requirement of the small-sized pressure relief mechanism 40.

It should be understood that the structure and the size of the weak portion 51 are set by the structure and the size of the pressure relief hole 21, so that the weak portion 51 can be better adapted to the pressure relief mechanism 40, thereby ensuring that the pressure relief mechanism 40 can be normally opened to reduce the safety risk of the battery cell 1.

It should be noted that the insulating member 50 is a rectangular plate with a width B and a projection 52 with a width B, wherein B/B is greater than or equal to 50%.

The insulating member 50 covers the pressure relief mechanism 40, so that the situation that high-temperature substances sprayed by the battery cell 1 with thermal runaway penetrate through the pressure relief mechanism 40 of the battery cell 1 without thermal runaway to cause thermal diffusion is avoided to a certain extent. Through set up weak part 51 on insulating part 50, when battery monomer 1 thermal runaway appears, the internal pressure of battery 100 inside increases, and when pressure reached the opening pressure of pressure relief mechanism 40, high temperature material broke pressure relief mechanism 40 and broken weak part 51 for insulating part 50 is cracked at weak part 51's position, with the normal opening that realizes pressure relief mechanism 40, thereby has reduced the safety risk.

In some embodiments of the present application, the insulation 50 is one of a mica piece, a ceramic piece, and a fiberglass piece.

Through setting up insulating part 50 into one of mica spare, ceramic member and glass fiber spare, not only can improve the intensity of insulating part, also can make insulating part 50 self have insulating and heat-proof quality simultaneously, avoided external environment to a certain extent to produce bad influence to pressure release mechanism.

In some embodiments of the present application, the insulation 50 is a composite of at least two of mica, ceramic, and fiberglass.

Through setting up insulating part 50 into the composite member of two kinds at least formation in mica part, ceramic member and the glass fiber spare, not only can improve the intensity of insulating part, also can make insulating part 50 self have insulating and heat-proof quality simultaneously, avoided external environment to a certain extent to produce bad influence to pressure release mechanism.

A second aspect of the present application proposes a battery 100 comprising: the battery cell 1 described above.

A third aspect of the present application proposes an electrical device comprising a battery 100 as described above, the battery 100 being configured to provide electrical energy.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

In the embodiment of the present application, as shown in fig. 4 to 8, the plurality of weak portions 51 are annularly provided outside the projection of the pressure relief hole 21 on the insulator 50 and formed in a raceway shape, wherein a region surrounded by the plurality of weak portions 51 is provided at equal intervals from the edge of the projection 52, the interval is 5mm (preferably 0.5 mm) or less, the interval between two adjacent weak portions 51 of the plurality of weak portions 51 is 2 to 6mm (preferably 4 mm), and the single weak portion 51 has a rectangular shape, and the width thereof has a width interval of [0.5mm,2mm [ ]](preferably 1.5 mm), and the length of the weak portion 51 is within a range of [4mm,8mm ]]The specific value is set according to the size of the pressure relief hole 21, and when the area of the projection 52 of the pressure relief hole 21 on the insulating member 50 is larger than 1000mm ² The length of the weak portion 51 is 7mm, and the area of the projection 52 of the pressure relief hole 21 on the insulator 50 is 1000mm or less ² The length of the weak portion 51 is 5mm.

By providing the plurality of weak portions 51 on the insulating member 50, and setting the spacing distance between two adjacent weak portions 51 and the length and width of the weak portions 51, when thermal runaway occurs in the battery cell 1, the internal pressure inside the case is increased, and when the pressure reaches the opening pressure of the pressure relief mechanism 40, the high-temperature substance breaks the pressure relief mechanism 40 and breaks the weak portions 51, so that the insulating member 50 is effectively broken at the weak portions 51 to realize normal opening of the pressure relief mechanism 40, thereby reducing the safety risk.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present disclosure, and the present disclosure should be construed as being covered by the claims and the specification. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims (11)

1. A battery cell, comprising:

the shell is provided with a pressure relief mechanism;

the insulation piece covers one side, far away from the shell, of the pressure relief mechanism, a plurality of weak portions are arranged on the insulation piece, the distance between every two adjacent weak portions in the weak portions is L, and L is larger than or equal to 2mm and smaller than or equal to 6mm.

2. The battery cell as recited in claim 1, wherein the plurality of weak portions are disposed in correspondence with the pressure relief mechanism.

3. The battery cell as recited in claim 1, wherein the plurality of weak portions are disposed at equal intervals.

4. The battery cell as recited in claim 1 wherein the weak portion is a through-hole or a recessed structure.

5. The battery cell as claimed in claim 1, wherein the housing is provided with a pressure relief hole for installing the pressure relief mechanism, and a projection of the pressure relief hole on the insulating member falls into an area surrounded by the plurality of weak portions.

6. The battery cell of claim 5, wherein a shortest distance between the plurality of weaknesses and the projected edge is D, wherein D e [0mm,5mm ].

7. The battery cell as recited in claim 1, wherein the plurality of weak portions are formed in a shape of a straight line, a zigzag, a curved line, a cross, an X, a circle, an ellipse, or a meter.

8. The battery cell of claim 1, wherein a single one of the weakened portions is rectangular in shape, the rectangle having a width M, wherein M e [0.5mm,2mm ]; and/or

The length of each rectangle is N, wherein N belongs to [4mm,8mm ].

9. The battery cell of claim 1, wherein the insulating member is one of a mica member, a ceramic member, and a fiberglass member;

or the insulating part is a composite part formed by at least two of the mica part, the ceramic part and the glass fiber part.

10. A battery, comprising: a battery cell according to any one of claims 1 to 9.

11. An electrical device comprising the battery of claim 10 or the cell of claim 9, wherein the battery or the cell is configured to provide electrical energy.

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