CN117242624A

CN117242624A - Pressure release mechanism, battery monomer, battery and electric equipment

Info

Publication number: CN117242624A
Application number: CN202280032499.7A
Authority: CN
Inventors: 陈小波; 白静峰; 顾明光
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-03-18
Filing date: 2022-03-18
Publication date: 2023-12-15
Also published as: WO2023173416A1

Abstract

The embodiment of the application provides a pressure release mechanism, a battery monomer, a battery and electric equipment, and belongs to the technical field of batteries. The pressure release mechanism comprises a pressure release body and a pressure release structure. The pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, and the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part which is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value. The second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove. The structure effectively avoids stress concentration of each pressure relief groove in the intersecting area, improves the anti-damage capability of the pressure relief mechanism, reduces the risk that the pressure of the pressure relief mechanism in the battery monomer begins to relieve pressure when the pressure in the battery monomer does not reach the detonation pressure, and improves the service life of the battery monomer.

Description

Pressure release mechanism, battery monomer, battery and electric equipment

Technical Field

The application relates to the technical field of batteries, in particular to a pressure release mechanism, a battery monomer, a battery and electric equipment.

Background

With the development of new energy technology, the battery is increasingly widely applied, for example, to mobile phones, notebook computers, battery cars, electric automobiles, electric airplanes, electric ships, electric toy automobiles, electric toy ships, electric toy airplanes, electric tools and the like.

In the battery technology, both the safety of the battery cell and the service life of the battery cell need to be considered, so how to improve the service life of the battery cell is a problem to be solved in the battery technology.

Disclosure of Invention

The embodiment of the application provides a pressure release mechanism, a battery monomer, a battery and electric equipment, which can effectively prolong the service life of the battery monomer.

In a first aspect, an embodiment of the present application provides a pressure relief mechanism for a battery cell, where the pressure relief mechanism includes a pressure relief body and a pressure relief structure; the pressure relief body is provided with a pressure relief part; the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and positioned in different directions, the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define the pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature in the battery cell reaches a threshold value so as to relieve the pressure in the battery cell; the second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.

Among the above-mentioned technical scheme, the second relief groove neither intersects with first relief groove, also does not intersect with the third relief groove, avoids each relief groove to produce stress concentration in crossing region, improves pressure release mechanism's vandalism ability, reduces pressure release mechanism and does not reach the risk that the detonation pressure just begins the pressure release in the inside pressure of battery monomer, improves battery monomer's life.

In some embodiments, the first pressure relief groove, the second pressure relief groove, and the third pressure relief groove together define two pressure relief portions, and the two pressure relief portions are respectively located at two sides of the second pressure relief groove. In the pressure relief process, two pressure relief portions can be opened fast in a split mode, and when guaranteeing to have enough pressure relief area, the opening efficiency of the pressure relief portions is improved, so that quick pressure relief is realized.

In some embodiments, the two pressure relief portions are symmetrically distributed on two sides of the second pressure relief groove. Like this, the size, the shape of two pressure release portions are the same, are favorable to two pressure release portions to open simultaneously, are difficult for appearing that one pressure release portion opens earlier, and the condition of opening after another pressure release portion does not open even.

In some embodiments, the distance between the first relief groove and the third relief groove increases gradually along the direction from the second relief groove to both ends of the first relief groove. When the pressure release, after the pressure release body splits along the second pressure release groove, the pressure release body will split along first pressure release groove and third pressure release groove for the pressure release portion opens with the mode of outside upset, because the distance between first pressure release groove and the third pressure release groove is the gradual increase from the position of second pressure release groove to first pressure release groove both ends, the pressure release portion is opening the in-process, and the open area of pressure release portion increases gradually, has increased the open area of pressure release portion on the one hand, and on the other hand makes pressure release portion open more smoothly.

In some embodiments, the first pressure relief groove, the second pressure relief groove and the third pressure relief groove together define one pressure relief portion, and the first pressure relief groove, the second pressure relief groove and the third pressure relief groove are respectively located at three adjacent edges of the pressure relief portion in different directions. The first pressure relief groove, the second pressure relief groove and the third pressure relief groove are only provided with one pressure relief part, the structure is simpler, and the forming cost of the pressure relief structure is reduced.

In some embodiments, the second relief groove has a first end facing the first relief groove, a gap between the first end and the first relief groove being no more than one third of a distance between the first relief groove and the third relief groove; and/or the second pressure relief groove has a second end facing the third pressure relief groove, and a gap between the second end and the third pressure relief groove is not more than one third of a distance between the first pressure relief groove and the third pressure relief groove. The gap between the first end and the first pressure relief groove is set in a reasonable range, so that after the pressure relief body is cracked along the second pressure relief groove, the crack can more easily extend to the first pressure relief groove, and the pressure relief body can be cracked along the first pressure relief groove smoothly; likewise, set up the clearance between second end and the third pressure release groove at reasonable within range, guarantee that the pressure release body splits the back along the second pressure release groove, the crack can spread to the third pressure release groove more easily to make the pressure release body split along the third pressure release groove smoothly afterwards, make pressure release portion can open more easily after the inside pressure of battery monomer reaches detonation pressure.

In some embodiments, the first relief groove is parallel to the third relief groove and perpendicular to the second relief groove. The pressure release portion shape that makes first pressure release groove, second pressure release groove and third pressure release groove define jointly is more regular, and during the pressure release, the pressure release body can open in step along first pressure release groove and third pressure release groove for pressure release portion opens more regularly, realizes more that pressure release portion opens completely.

In some embodiments, the first pressure relief groove includes a plurality of first groove portions, the plurality of first groove portions being sequentially disposed along a depth direction of the first pressure relief groove, and a plurality of first groove portions being gradually reduced in width along the depth direction of the first pressure relief groove. The first pressure release groove adopts multistage groove structure, can reduce the shaping power that the pressure release body received when shaping every stage groove, reduces the risk that the pressure release body produced the crackle at the in-process in shaping first pressure release groove, improves pressure release mechanism's long-term reliability.

In some embodiments, the second pressure relief groove includes a plurality of second groove portions, the plurality of second groove portions being sequentially disposed along a depth direction of the second pressure relief groove, and a plurality of second groove portions being gradually reduced in width along the depth direction of the second pressure relief groove. The second pressure release groove adopts multistage groove structure, can reduce the shaping power that the pressure release body received when shaping every stage groove, reduces the risk that the pressure release body produced the crackle at the in-process in shaping second pressure release groove, improves pressure release mechanism's long-term reliability.

In some embodiments, the third pressure relief groove includes a plurality of third groove portions, the plurality of third groove portions are sequentially disposed along a depth direction of the third pressure relief groove, and a width of the plurality of third groove portions gradually decreases along the depth direction of the third pressure relief groove. The third pressure release groove adopts multistage groove structure, can reduce the shaping power that the pressure release body received when shaping every stage groove, reduces the risk that the pressure release body produced the crackle at the in-process in shaping third pressure release groove, improves pressure release mechanism's long-term reliability.

In some embodiments, the pressure relief body is internally formed with a receiving space for receiving an electrode assembly, the pressure relief body having a plurality of walls that collectively define the receiving space, at least one of the walls being provided with the pressure relief structure. Thus, the pressure relief mechanism is a shell capable of accommodating the electrode assembly, and the pressure relief mechanism integrates an accommodating function and a pressure relief function.

In a second aspect, an embodiment of the present application provides a battery monomer, including the pressure relief mechanism provided in any one of the embodiments of the first aspect.

In a third aspect, an embodiment of the present application provides a battery, including a case and a battery cell provided in any one of the embodiments of the second aspect; the box is used for accommodating the battery cells.

In a fourth aspect, an embodiment of the present application provides an electric device, including a battery provided in any one of the embodiments of the third aspect.

In a fifth aspect, an embodiment of the present application provides a method for manufacturing a pressure relief mechanism, including: providing a pressure relief body; processing a pressure relief structure on the pressure relief body; the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value so as to relieve the pressure inside the battery cell; the second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.

In a sixth aspect, an embodiment of the present application further provides a manufacturing apparatus for a pressure relief mechanism, where the manufacturing apparatus includes a providing device and a processing device; the providing device is used for providing the pressure relief body; the processing device is used for processing the pressure relief structure on the pressure relief body; the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value so as to relieve the pressure inside the battery cell; the second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;

fig. 2 is an exploded view of a battery provided in some embodiments of the present application;

fig. 3 is an exploded view of a battery cell according to some embodiments of the present application;

FIG. 4 is an enlarged view of a portion of a pressure relief mechanism provided in some embodiments of the present application;

FIG. 5 is an enlarged view of a portion of a pressure relief mechanism according to further embodiments of the present application;

FIG. 6 is an enlarged view of a portion of a pressure relief mechanism provided in accordance with further embodiments of the present application;

FIG. 7 is a cross-sectional view A-A of the pressure relief mechanism shown in FIG. 4;

FIG. 8 is a B-B cross-sectional view of the pressure relief mechanism shown in FIG. 4;

FIG. 9 is a C-C cross-sectional view of the pressure relief mechanism shown in FIG. 4;

FIG. 10 is a schematic diagram of a pressure relief mechanism according to still other embodiments of the present application;

FIG. 11 is a flow chart of a method of manufacturing a pressure relief mechanism according to some embodiments of the present application;

fig. 12 is a schematic block diagram of a manufacturing apparatus for a pressure relief mechanism provided in some embodiments of the present application.

Icon: 10-a box body; 11-a first part; 12-a second part; 20-battery cells; 21-a housing; 22-electrode assembly; 221-positive electrode tab; 222-a negative electrode tab; 23-end caps; 231-positive electrode terminal; 232-a negative electrode terminal; 24-current collecting member; 25-a pressure release mechanism; 251-decompression body; 2511—a pressure relief section; 252-pressure relief structure; 2521-a first pressure relief tank; 2521 c-a first slot section; 2522-a second pressure relief tank; 2522 a-first end; 2522 b-second end; 2522 c-a second slot section; 2523-a third pressure relief tank; 2523 c-a third slot section; 100-cell; 200-a controller; 300-motor; 1000-vehicle; 2000-manufacturing equipment; 2100-providing means; 2200-a processing device; z-depth direction.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

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 in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases 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.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.

In the embodiments of the present application, the same reference numerals denote the same components, and detailed descriptions of the same components are omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width, etc. dimensions of the various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length, width, etc. dimensions of the integrated device, are merely illustrative and should not be construed as limiting the application in any way.

The term "plurality" as used herein refers to two or more (including two).

In the present application, the battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited in the embodiment of the present application. The battery cell may be in a cylindrical shape, a flat shape, a rectangular parallelepiped shape, or other shapes, which is not limited in this embodiment of the application. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited in this embodiment.

Reference to a battery in accordance with an embodiment of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, or the like. The battery generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly consists of a positive electrode plate, a negative electrode plate and a separation film. The battery cell mainly relies on metal ions to move between the positive pole piece and the negative pole piece to work. The positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the positive electrode current collector without the positive electrode active material layer protrudes out of the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector without the positive electrode active material layer is used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate or the like. The negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, the negative electrode current collector without the negative electrode active material layer protrudes out of the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector without the negative electrode active material layer is used as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the high current is passed without fusing, the number of positive electrode lugs is multiple and stacked together, and the number of negative electrode lugs is multiple and stacked together. The material of the separator may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may be a roll-to-roll structure or a lamination structure, and embodiments of the present application are not limited thereto.

The development of battery technology is taking into consideration various design factors such as energy density, cycle life, discharge capacity, charge-discharge rate and other performance parameters, and the safety of the battery.

The pressure release mechanism on the battery monomer has an important influence on the safety of the battery. For example, when a short circuit, overcharge, or the like occurs, thermal runaway may occur inside the battery cell, and thus pressure or temperature rises. In this case, the pressure and temperature inside the battery can be released outwards through the pressure release mechanism, so that the explosion and the ignition of the battery cell can be prevented.

The inventor notes that for a general pressure relief mechanism, after a period of use, the pressure relief mechanism is easy to start to relieve pressure when the internal pressure of the battery monomer does not reach the detonation pressure, so that the battery monomer is invalid, and the service life of the battery monomer is short.

The inventor finds that for a general pressure relief mechanism, a plurality of pressure relief grooves positioned in different directions are generally arranged on a pressure relief body, a pressure relief part is defined by the plurality of pressure relief grooves, two adjacent pressure relief grooves are intersected, and the pressure relief part is opened when the pressure or the temperature in the battery cell reaches a threshold value so as to relieve the pressure in the battery cell. In an actual working environment, the internal pressure of the battery cell changes along with the change of the ambient temperature, when the temperature rises, the internal pressure of the battery cell rises, and when the temperature falls, the internal pressure of the battery cell falls. Because two adjacent pressure release grooves in the pressure release mechanism intersect, the intersecting region easily produces stress concentration, and the pressure inside the battery monomer changes back along with the change of temperature is long-term alternately, and fatigue phenomenon appears in the region that two pressure release grooves intersect most easily, leads to pressure release mechanism not enough in the regional vandalism ability of two pressure release grooves intersection, and is easiest to split, appears the pressure release mechanism in the inside pressure of battery monomer and does not reach the condition that the detonation pressure just begins the pressure release easily, influences the free life of battery.

In view of this, an embodiment of the present application provides a pressure relief mechanism, which includes a pressure relief body and a pressure relief structure. The pressure release body is provided with a pressure release part. The pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value so as to relieve the pressure inside the battery cell. The second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.

In such relief mechanism, the second relief groove neither intersects with first relief groove, also does not intersect with the third relief groove, avoids each relief groove to produce stress concentration in crossing region, improves relief mechanism's vandalism ability, reduces relief mechanism and does not reach the risk that the detonation pressure just begins the pressure release at the inside pressure of battery monomer, improves battery monomer's life.

The pressure relief mechanism described by the embodiment of the application is suitable for a battery monomer, a battery and electric equipment using the battery.

The electric equipment can be vehicles, mobile phones, portable equipment, notebook computers, ships, spacecrafts, electric toys, electric tools and the like. The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the application does not limit the electric equipment in particular.

For convenience of explanation, the following embodiments take electric equipment as an example of a vehicle.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application, a battery 100 is disposed in the vehicle 1000, and the battery 100 may be disposed 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 be used as an operating power source of the vehicle 1000.

The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

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

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present application, where the battery 100 includes a case 10 and a battery cell 20, and the case 10 is used for accommodating the battery cell 20.

The case 10 is a component for accommodating the battery cell 20, the case 10 provides an accommodating cavity for the battery cell 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 being overlapped with each other to define a receiving chamber for receiving the battery cell 20. The first portion 11 and the second portion 12 may be of various shapes, such as a rectangular parallelepiped, a cylinder, or the like. The first portion 11 may be a hollow structure with one side opened, and the second portion 12 may be a hollow structure with one side opened, and the open side of the second portion 12 is closed to the open side of the first portion 11, so as to form the case 10 having the accommodating cavity. The first portion 11 may be a hollow structure with one side open, the second portion 12 may be a plate-like structure, and the second portion 12 may be covered on the open side of the first portion 11 to form the case 10 having the accommodating chamber. The first portion 11 and the second portion 12 may be sealed by a sealing element, which may be a sealing ring, a sealant or the like.

In the battery 100, the number of the battery cells 20 may be one or a plurality. If there are multiple battery cells 20, the multiple battery cells 20 may be connected in series or parallel or a series-parallel connection, where a series-parallel connection refers to that there are both series connection and parallel connection among the multiple battery cells 20. The plurality of battery cells 20 may be connected in series or parallel or in series-parallel to form a battery module, and then connected in series or parallel or in series-parallel to form a whole and be accommodated in the case 10. All the battery cells 20 may be directly connected in series, parallel or series-parallel, and then the whole body formed by all the battery cells 20 is accommodated in the case 10.

In some embodiments, the battery 100 may further include a bus member through which electrical connection between the plurality of battery cells 20 may be achieved to enable serial or parallel connection or series-parallel connection of the plurality of battery cells 20. The bus member may be a metal conductor such as copper, iron, aluminum, stainless steel, aluminum alloy, or the like.

Referring to fig. 3, fig. 3 is an exploded view of a battery cell 20 according to some embodiments of the present application, and the battery cell 20 includes a case 21, an electrode assembly 22, and an end cap 23.

The case 21 is a member for accommodating the electrode assembly 22, and the case 21 may be a hollow structure having one end formed to be open, and the case 21 may be a hollow structure having opposite ends formed to be open. The housing 21 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or the like. The material of the housing 21 may be various, such as copper, iron, aluminum, steel, aluminum alloy, etc.

The number of the electrode assemblies 22 in the case 21 may be one or more. For example, as shown in fig. 3, the case 21 has a rectangular parallelepiped structure, and a plurality of electrode assemblies 22 are provided, and a plurality of electrode assemblies 22 are stacked.

The electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell 20. The electrode assembly 22 may include a positive electrode tab, a negative electrode tab, and a separator. The electrode assembly 22 may be a wound structure formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, or may be a laminated structure formed by stacking a positive electrode sheet, a separator, and a negative electrode sheet. The electrode assembly 22 has a positive electrode tab 221 and a negative electrode tab 222, the positive electrode tab 221 may be a portion of the positive electrode sheet on which the positive electrode active material layer is not coated, and the negative electrode tab 222 may be a portion of the negative electrode sheet on which the negative electrode active material layer is not coated.

The end cap 23 is a member that covers the opening of the case 21 to isolate the internal environment of the battery cell 20 from the external environment. The end cap 23 is covered on the opening of the case 21, and the end cap 23 and the case 21 together define a sealed space for accommodating the electrode assembly 22, the electrolyte, and other components. The shape of the end cover 23 may be adapted to the shape of the housing 21, for example, the housing 21 is a cuboid structure, the end cover 23 is a rectangular plate structure adapted to the housing 21, for example, the housing 21 is a cylindrical structure, and the end cover 23 is a circular plate structure adapted to the housing 21. The material of the end cap 23 may be various, such as copper, iron, aluminum, steel, aluminum alloy, etc.

In the battery cell 20, the end caps 23 may be one or two. If the housing 21 is a hollow structure having one end formed with an opening, the end caps 23 are provided one for each. If the housing 21 has a hollow structure with openings formed at both ends, two end caps 23 are provided, and the two end caps 23 cover the two openings of the housing 21, respectively.

Electrode terminals may be provided on the end caps 23, and the electrode terminals are electrically connected to the tabs to output the electric power of the battery cells 20. The electrode terminals may be divided into a positive electrode terminal 231 for electrically connecting with the positive electrode tab 221 and a negative electrode terminal 232 for electrically connecting with the negative electrode tab 222. The positive electrode terminal 231 and the negative electrode terminal 232 may be provided on the same end cap 23, or may be provided on different end caps 23. For example, the case 21 has a hollow structure with openings formed at both ends, two end caps 23 in the battery cell 20 are provided, the two end caps 23 are correspondingly covered on the two openings of the case 21, the negative electrode terminal 232 is provided on one end cap 23, and the positive electrode terminal 231 is provided on the other end cap 23. As another example, as shown in fig. 3, the case 21 has a hollow structure with one end opened, one end cap 23 in the battery cell 20, and the negative electrode terminal 232 and the positive electrode terminal 231 may be disposed on the same end cap 23.

The positive electrode terminal 231 and the positive electrode tab 221 may be directly connected or indirectly connected, and the negative electrode terminal 232 and the negative electrode tab 222 may be directly connected or indirectly connected. Illustratively, the positive electrode terminal 231 is indirectly connected to the positive electrode tab 221 through one current collecting member 24, and the negative electrode terminal 232 is indirectly connected to the negative electrode tab 222 through the other current collecting member 24.

To ensure the safety of the battery cell 20, a pressure relief mechanism 25 (not shown in fig. 3) may be provided in the battery cell 20, and when the pressure or temperature inside the battery cell 20 reaches a threshold value, the pressure inside the battery cell 20 is relieved through the pressure relief mechanism 25. The specific structure of the pressure release mechanism 25 is described in detail below with reference to the drawings.

Referring to fig. 4, fig. 4 is a partial enlarged view of a pressure release mechanism 25 according to some embodiments of the present application, and the embodiment of the present application provides a pressure release mechanism 25 for a battery cell 20, where the pressure release mechanism 25 includes a pressure release body 251 and a pressure release structure 252. The relief body 251 has a relief portion 2511. The pressure relief structure 252 includes a first pressure relief groove 2521, a second pressure relief groove 2522, and a third pressure relief groove 2523 disposed on the pressure relief body 251 and located in different orientations, where the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 together define a pressure relief portion 2511, and the pressure relief portion 2511 is configured to be opened with the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 as boundaries when the pressure or the temperature inside the battery cell 20 reaches a threshold value, so as to relieve the pressure inside the battery cell 20. Wherein the second pressure relief groove 2522 is located between the first pressure relief groove 2521 and the third pressure relief groove 2523, and is not intersected with the first pressure relief groove 2521 and the third pressure relief groove 2523.

In the battery cell 20, the pressure release body 251 may be a separate component mounted on the case 21 or the end cap 23, for example, the pressure release body 251 is a plate-shaped structure mounted on the end cap 23, and in particular, the pressure release body 251 may be a rupture disk mounted on the end cap 23; the housing 21 or the end cap 23 itself may be used as the pressure relief body 251.

The first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 may be formed in various manners, such as engraving, stamping, milling, etc., to which the embodiment of the present application is not particularly limited. The first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 are three pressure relief grooves located in different orientations, and the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 may be linear grooves extending along a linear track, or may be non-linear grooves, such as arc grooves. If the first pressure relief groove 2521, the second pressure relief groove 2522 and the third pressure relief groove 2523 are straight grooves, the first pressure relief groove 2521 and the third pressure relief groove 2523 may be arranged in parallel or may be arranged in non-parallel; the first pressure relief groove 2521 and the second pressure relief groove 2522 may be vertically arranged or non-vertically arranged; the third pressure relief groove 2523 and the second pressure relief groove 2522 may be vertically arranged or may be vertically arranged.

The relief portion 2511 is an area of the relief body 251 defined by the first relief groove 2521, the second relief groove 2522 and the third relief groove 2523, but this does not mean that the first relief groove 2521 and the third relief groove 2523 are connected to the second relief groove 2522, and it is understood that the first relief groove 2521, the second relief groove 2522 and the third relief groove 2523 are respectively located at three adjacent edge positions of the relief portion 2511. The pressure relief portion 2511 defined by the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 may be one or two.

When the pressure or temperature inside the battery cell 20 reaches a threshold value, the relief portion 2511 opens with the first relief groove 2521, the second relief groove 2522, and the third relief groove 2523 as boundaries. It may be that the pressure release body 251 is first cracked along the second pressure release groove 2522, and after the crack generated by cracking the second pressure release groove 2522 propagates to the first pressure release groove 2521 and the third pressure release groove 2523, the pressure release body 251 is cracked along the first pressure release groove 2521 and the third pressure release groove 2523, so that the pressure release portion 2511 is finally opened. After the pressure relief portion 2511 is opened, the pressure relief body 251 forms an opening at a position corresponding to the pressure relief portion 2511, and the exhaust (gas, electrolyte, etc.) inside the battery cell 20 can be discharged through the opening, thereby achieving the purpose of relieving the pressure inside the battery cell 20. The pressure relief portion 2511 is turned outwardly in the flow direction of the exhaust inside the battery cell 20 during the opening process of the pressure relief portion 2511.

The second pressure relief groove 2522 is not intersected with the first pressure relief groove 2521, that is, the second pressure relief groove 2522 is not connected with the first pressure relief groove 2521, and a gap exists between one end, close to the first pressure relief groove 2521, of the second pressure relief groove 2522 and the first pressure relief groove 2521. The second pressure relief groove 2522 is not intersected with the third pressure relief groove 2523, that is, the second pressure relief groove 2522 and the third pressure relief groove 2523 are not connected together, and a gap exists between one end of the second pressure relief groove 2522 close to the third pressure relief groove 2523 and the third pressure relief groove 2523.

In the embodiment of the application, the second pressure release groove 2522 does not intersect with the first pressure release groove 2521 or the third pressure release groove 2523, so that stress concentration of each pressure release groove in an intersecting area is avoided, the anti-damage capability of the pressure release mechanism 25 is improved, the risk that the pressure of the pressure release mechanism 25 in the battery cell 20 begins to release pressure when the pressure does not reach the detonation pressure is reduced, and the service life of the battery cell 20 is prolonged.

In some embodiments, referring to fig. 4, the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 together define two pressure relief portions 2511, and the two pressure relief portions 2511 are respectively located at two sides of the second pressure relief groove 2522.

The two pressure relief portions 2511 are located on two sides of the second pressure relief groove 2522, respectively, and it is understood that the two pressure relief portions 2511 are bounded by the second pressure relief groove 2522. The two pressure release portions 2511 may be equal in size or different in size. The first pressure relief groove 2521 and the third pressure relief groove 2523 may be arranged at equal intervals, for example, the first pressure relief groove 2521 is parallel to the third pressure relief groove 2523; of course, the first pressure relief groove 2521 and the third pressure relief groove 2523 may also be arranged with a variable pitch. For example, in fig. 4, the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 are all straight grooves, the first pressure relief groove 2521 is parallel to the third pressure relief groove 2523, and the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 have a substantially "H" shape structure.

In the pressure relief process, the two pressure relief portions 2511 can be opened rapidly in a split manner, so that the opening efficiency of the pressure relief portions 2511 is improved while the sufficient pressure relief area is ensured, and rapid pressure relief is realized.

In some embodiments, the two pressure relief portions 2511 are symmetrically distributed on both sides of the second pressure relief slot 2522.

The second relief groove 2522 may be considered as an axis of symmetry for the two relief portions 2511, with the two relief portions 2511 being symmetrical about the second relief groove 2522. As shown in fig. 4, taking the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 as linear grooves, the first pressure relief groove 2521 may be parallel to the third pressure relief groove 2523, the first pressure relief groove 2521 is perpendicular to the second pressure relief groove 2522, and the second pressure relief groove 2522 is disposed at a midpoint position of the first pressure relief groove 2521 and the third pressure relief groove 2523, so as to realize that the pressure relief portions 2511 are symmetrically distributed on two sides of the second pressure relief groove 2522.

In this embodiment, the two pressure relief portions 2511 are symmetrically distributed on two sides of the second pressure relief groove 2522, and the two pressure relief portions 2511 have the same size and shape, so that the two pressure relief portions 2511 are opened simultaneously, and the situation that one pressure relief portion 2511 is opened first, the other pressure relief portion 2511 is opened after, and even is not opened is avoided.

In some embodiments, referring to fig. 5, fig. 5 is a partially enlarged view of a pressure relief mechanism 25 according to another embodiment of the application, wherein a distance between the first pressure relief groove 2521 and the third pressure relief groove 2523 gradually increases along a direction from the second pressure relief groove 2522 to both ends of the first pressure relief groove 2521.

For example, the first pressure relief groove 2521 and the third pressure relief groove 2523 are polygonal grooves extending along a V-shaped track, and the first pressure relief groove 2521 and the third pressure relief groove 2523 are symmetrically arranged, so that the pressure relief portions 2511 located at two sides of the second pressure relief groove 2522 are in an isosceles trapezoid structure.

During pressure relief, after the pressure relief body 251 is split along the second pressure relief groove 2522, the pressure relief body 251 will split along the first pressure relief groove 2521 and the third pressure relief groove 2523, so that the pressure relief portion 2511 is opened in an outwards turned manner, and as the distance between the first pressure relief groove 2521 and the third pressure relief groove 2523 is gradually increased from the position of the second pressure relief groove 2522 to the two ends of the first pressure relief groove 2521, the opening area of the pressure relief portion 2511 is gradually increased in the opening process of the pressure relief portion 2511, on one hand, the opening area of the pressure relief portion 2511 is increased, and on the other hand, the pressure relief portion 2511 is opened more smoothly.

In some embodiments, referring to fig. 6, fig. 6 is a partially enlarged view of a pressure relief mechanism 25 according to still other embodiments of the present application, where a first pressure relief groove 2521, a second pressure relief groove 2522 and a third pressure relief groove 2523 together define a pressure relief portion 2511, and the first pressure relief groove 2521, the second pressure relief groove 2522 and the third pressure relief groove 2523 are respectively located at three adjacent edges of the pressure relief portion 2511 in different orientations.

The first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 are linear grooves, and the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 have a substantially "" shape.

In this embodiment, the first pressure relief groove 2521, the second pressure relief groove 2522 and the third pressure relief groove 2523 define only one pressure relief portion 2511, which is simpler in structure and reduces the molding cost of the pressure relief structure 252.

In some embodiments, referring to fig. 4-6, the second pressure relief groove 2522 has a first end 2522a facing the first pressure relief groove 2521, and a gap L1 between the first end 2522a and the first pressure relief groove 2521 is not greater than one third of a distance D between the first pressure relief groove 2521 and the third pressure relief groove 2523; and/or, the second relief groove 2522 has a second end 2522b facing the third relief groove 2523, the gap L2 between the second end 2522b and the third relief groove 2523 being no more than one third of the distance D between the first relief groove 2521 and the third relief groove 2523.

The distance D between the first pressure release groove 2521 and the third pressure release groove 2523 is the distance between the positions of the first pressure release groove 2521 and the third pressure release groove 2523 corresponding to the second pressure release groove 2522. As shown in fig. 5, in the embodiment in which the distance between the first pressure release groove 2521 and the second pressure release groove 2522 gradually increases from the position of the second pressure release groove 2522 to the two ends of the first pressure release groove 2521, the distance D between the first pressure release groove 2521 and the third pressure release groove 2523 is the distance between the positions of the first pressure release groove 2521 and the third pressure release groove 2523 corresponding to the second pressure release groove 2522, that is, the minimum distance between the first pressure release groove 2521 and the third pressure release groove 2523.

In actual measurement, the gap L1 between the first end 2522a and the first pressure relief groove 2521 and the distance D between the first pressure relief groove 2521 and the third pressure relief groove 2523 may be measured in the same direction, and similarly, the gap L2 between the second end 2522b and the third pressure relief groove 2523 and the distance D between the first pressure relief groove 2521 and the third pressure relief groove 2523 may be measured in the same direction.

In the present embodiment, the gap L1 between the first end 2522a and the first pressure relief groove 2521 is set within a reasonable range, so that after the pressure relief body 251 is cracked along the second pressure relief groove 2522, the crack can more easily linger to the first pressure relief groove 2521, and the pressure relief body 251 can then be cracked along the first pressure relief groove 2521 smoothly; also, setting the gap L2 between the second end 2522b and the third pressure relief groove 2523 within a reasonable range ensures that the crack can more easily propagate to the third pressure relief groove 2523 after the pressure relief body 251 is ruptured along the second pressure relief groove 2522, so that the pressure relief body 251 can be subsequently ruptured along the third pressure relief groove 2523 smoothly, and the pressure relief portion 2511 can be opened more easily after the internal pressure of the battery cell 20 reaches the detonation pressure.

In some embodiments, referring to fig. 4 and 6, the first pressure relief groove 2521 is parallel to the third pressure relief groove 2523, and the first pressure relief groove 2521 is perpendicular to the second pressure relief groove 2522.

Illustratively, the first, second, and third relief slots 2521, 2522, and 2523 are all linear slots.

In this embodiment, the shape of the pressure relief portion 2511 defined by the first pressure relief groove 2521, the second pressure relief groove 2522 and the third pressure relief groove 2523 is more regular, and when pressure relief is performed, the pressure relief body 251 can be synchronously split along the first pressure relief groove 2521 and the third pressure relief groove 2523, so that the pressure relief portion 2511 is more regularly opened, and the pressure relief portion 2511 is easier to be completely opened.

In some embodiments, referring to fig. 7, fig. 7 is a cross-sectional view of A-A of the pressure relief mechanism 25 shown in fig. 4, the first pressure relief groove 2521 includes a plurality of first groove portions 2521c, the plurality of first groove portions 2521c are sequentially arranged along a depth direction Z of the first pressure relief groove 2521, and the width of the plurality of first groove portions 2521c is gradually reduced along the depth direction Z of the first pressure relief groove 2521.

The extending directions of the first groove portions 2521c in the first pressure release groove 2521 are the same, and if the first pressure release groove 2521 extends along a straight line trajectory, the first groove portions 2521c also extend along a straight line trajectory. The depth of each first pressure release groove 2521 may be equal or different, for example, the depth of each first groove portion 2521c gradually decreases along the depth direction Z of the first pressure release groove 2521.

The number of first groove portions 2521c in the first pressure release groove 2521 may be two, three, four or more. For example, in fig. 7, three first grooves 2521c in the first pressure relief groove 2521 are formed by punching, and in the forming, the first groove 2521c may be punched on the surface of the pressure relief body 251, then the second first groove 2521c may be punched on the bottom surface of the first groove 2521c, and finally the third first groove 2521c may be punched on the bottom surface of the second first groove 2521c. It is appreciated that the width of the first slot 2521c is greater than the width of the second first slot 2521c, and that the width of the second first slot 2521c is greater than the width of the third first slot 2521c.

In this embodiment, the first pressure relief groove 2521 adopts a multi-stage groove structure, so that the molding force applied to the pressure relief body 251 during molding each stage of groove can be reduced, the risk of cracking of the pressure relief body 251 during molding the first pressure relief groove 2521 is reduced, and the long-term reliability of the pressure relief mechanism 25 is improved.

In some embodiments, referring to fig. 8, fig. 8 is a B-B cross-sectional view of the pressure release mechanism 25 shown in fig. 4, the second pressure release groove 2522 includes a plurality of second groove portions 2522c, the plurality of second groove portions 2522c are sequentially arranged along a depth direction Z of the second pressure release groove 2522, and the width of the plurality of second groove portions 2522c is gradually reduced along the depth direction Z of the second pressure release groove 2522.

The extending directions of the second groove portions 2522c in the second pressure release groove 2522 are the same, and if the second pressure release groove 2522 extends along a straight line trajectory, the second groove portions 2522c also extend along a straight line trajectory. The depth of each second pressure release groove 2522 may be equal or may be different, for example, the depth of each second groove portion 2522c gradually decreases along the depth direction Z of the second pressure release groove 2522.

The number of second groove portions 2522c in the second pressure release groove 2522 may be two, three, four or more. For example, in fig. 8, three second grooves 2522c in the second pressure relief groove 2522 are exemplified by the second pressure relief groove 2522 being formed by punching, in which a first second groove 2522c may be punched on the surface of the pressure relief body 251, then a second groove 2522c may be punched on the bottom surface of the first second groove 2522c, and finally a third second groove 2522c may be punched on the bottom surface of the second groove 2522c. It is understood that the width of the first second groove 2522c is greater than the width of the second groove 2522c, and the width of the second groove 2522c is greater than the width of the third second groove 2522c.

In this embodiment, the second pressure relief groove 2522 adopts a multi-stage groove structure, so that the molding force applied to the pressure relief body 251 during molding each stage of groove can be reduced, the risk of cracking of the pressure relief body 251 during molding the second pressure relief groove 2522 is reduced, and the long-term reliability of the pressure relief mechanism 25 is improved.

In some embodiments, referring to fig. 9, fig. 9 is a C-C cross-sectional view of the pressure release mechanism 25 shown in fig. 4, the third pressure release groove 2523 includes a plurality of third groove portions 2523C, the plurality of third groove portions 2523C are sequentially arranged along a depth direction Z of the third pressure release groove 2523, and the width of the plurality of third groove portions 2523C is gradually reduced along the depth direction Z of the third pressure release groove 2523.

The extending directions of the third groove portions 2523c in the third pressure release groove 2523 are the same, and if the third pressure release groove 2523 extends along a straight line trajectory, the third groove portions 2523c also extend along a straight line trajectory. The depth of each third pressure release groove 2523 may be equal or may be different, for example, the depth of each third groove portion 2523c gradually decreases along the depth direction Z of the third pressure release groove 2523.

The number of third groove portions 2523c in the third pressure release groove 2523 may be two, three, four or more. For example, in fig. 8, three third grooves 2523c in the third pressure relief groove 2523 are formed by punching, and in the forming, a first third groove 2523c may be punched on the surface of the pressure relief body 251, then a second third groove 2523c may be punched on the bottom surface of the first third groove 2523c, and finally a third groove 2523c may be punched on the bottom surface of the second third groove 2523c. It is appreciated that the width of the first third groove 2523c is greater than the width of the second third groove 2523c, and that the width of the second third groove 2523c is greater than the width of the third groove 2523c.

In this embodiment, the third pressure relief groove 2523 has a multi-stage groove structure, so that the molding force applied to the pressure relief body 251 during molding each stage of groove can be reduced, the risk of cracking of the pressure relief body 251 during molding the third pressure relief groove 2523 is reduced, and the long-term reliability of the pressure relief mechanism 25 is improved.

In some embodiments, referring to fig. 10, fig. 10 is a schematic structural diagram of a pressure relief mechanism 25 according to still other embodiments of the present application, a containing space for containing an electrode assembly 22 is formed inside a pressure relief body 251, the pressure relief body 251 has a plurality of walls that together define the containing space, and at least one wall is provided with a pressure relief structure 252.

The pressure release body 251 may serve as the housing 21 of the battery cell 20. It will be appreciated that only one wall may be provided with the relief structure 252, or that multiple walls may each be provided with the relief structure 252. The pressure relief structure 252 may be provided on the outer surface of the wall or on the inner surface of the wall.

The pressure relief body 251 can be of various shapes, such as a cuboid, a cylinder. Taking the pressure relief body 251 as a cuboid for example, the pressure relief body 251 may have five walls, a bottom wall and four side walls enclose together to form an accommodating space with one open end, and the bottom wall and/or the side walls may be provided with a pressure relief structure 252. Taking the pressure release body 251 as a cylinder as an example, the pressure release body 251 may have two walls, a bottom wall and a circumferential wall, the circumferential wall encloses the edge of the bottom wall, the circumferential wall and the bottom wall enclose together to form an accommodating space with one open end, and the bottom wall and/or the side wall may be provided with a pressure release structure 252.

Illustratively, in fig. 10, the pressure relief body 251 has a rectangular parallelepiped structure, and the pressure relief structure 252 is disposed on an outer surface of the bottom wall.

In the present embodiment, the pressure relief mechanism 25 is a case capable of accommodating the electrode assembly 22, and the pressure relief mechanism 25 integrates an accommodating function and a pressure relief function.

An embodiment of the present application provides a battery cell 20, including the pressure release mechanism 25 provided in any one of the embodiments above.

An embodiment of the present application provides a battery 100, including a case 10 and the battery cells 20 provided in any one of the embodiments above, where the case 10 is used to accommodate the battery cells 20.

An embodiment of the present application provides an electric device, including the battery 100 provided in any one of the embodiments above.

The powered device may be any of the devices described above that employ battery 100.

Referring to fig. 10, an embodiment of the present application further provides a housing for accommodating the electrode assembly 22, and a pressure relief structure 252 is provided on the housing. The pressure relief structure 252 includes a first pressure relief groove 2521, a second pressure relief groove 2522, and a third pressure relief groove 2523 disposed on an outer surface of the casing and located in different orientations, the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 jointly define two pressure relief portions 2511, the two pressure relief portions 2511 are respectively located at two sides of the second pressure relief groove 2522, and the pressure relief portions 2511 are configured to be opened with the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 as boundaries when the pressure or the temperature inside the battery cell 20 reaches a threshold value, so as to relieve the pressure inside the battery cell 20. Wherein the second pressure relief groove 2522 is located between the first pressure relief groove 2521 and the third pressure relief groove 2523, and is not intersected with the first pressure relief groove 2521 and the third pressure relief groove 2523.

In such a case, the second pressure release groove 2522 does not intersect with the first pressure release groove 2521 or the third pressure release groove 2523, so that stress concentration of each pressure release groove in an intersecting region is avoided, the anti-damage capability of the case is improved, the risk that the case starts to release pressure when the pressure inside the battery cell 20 does not reach the detonation pressure is reduced, and the service life of the battery cell 20 is prolonged.

Referring to fig. 11, fig. 11 is a flowchart of a method for manufacturing a pressure release mechanism 25 according to some embodiments of the present application, where the method for manufacturing a pressure release mechanism 25 includes:

s100: providing a pressure relief body 251;

s200: a relief structure 252 is machined into the relief body 251.

The pressure relief structure 252 includes a first pressure relief groove 2521, a second pressure relief groove 2522, and a third pressure relief groove 2523 disposed on the pressure relief body 251 and located in different orientations, where the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 together define a pressure relief portion 2511, and the pressure relief portion 2511 is configured to be opened with the first pressure relief groove 2521, the second pressure relief groove 2522, and the third pressure relief groove 2523 as boundaries when the pressure or the temperature inside the battery cell 20 reaches a threshold value, so as to relieve the pressure inside the battery cell 20. The second relief groove 2522 is located between the first relief groove 2521 and the third relief groove 2523 and is non-intersecting with the first relief groove 2521 and the third relief groove 2523.

It should be noted that, the related structure of the pressure release mechanism 25 manufactured by the manufacturing method provided by the above embodiments can be referred to the pressure release mechanism 25 provided by each of the above embodiments, and will not be described herein again.

Referring to fig. 12, fig. 12 is a schematic block diagram of an apparatus 2000 for manufacturing a pressure relief mechanism 25 according to some embodiments of the present application, and an apparatus 2000 for manufacturing a pressure relief mechanism 25 according to an embodiment of the present application is further provided, where the apparatus 2000 includes a providing device 2100 and a processing device 2200. The providing device 2100 is used to provide the pressure relief body 251. The processing device 2200 is used for processing the pressure relief structure 252 on the pressure relief body 251.

It should be noted that, regarding the structure of the pressure relief mechanism 25 manufactured by the manufacturing apparatus 2000 provided in the foregoing embodiments, reference may be made to the pressure relief mechanism 25 provided in each of the foregoing embodiments, and the description thereof is omitted herein.

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.

The above embodiments are only for illustrating the technical solution of the present application, and are not intended to limit the present application, and various modifications and variations of the present application will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

A pressure relief mechanism for a battery cell, the pressure relief mechanism comprising:

the pressure relief body is provided with a pressure relief part;

the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and positioned in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define the pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature in the battery cell reaches a threshold value so as to relieve the pressure in the battery cell;

The second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.
The pressure relief mechanism of claim 1, wherein the first pressure relief groove, the second pressure relief groove, and the third pressure relief groove together define two pressure relief portions, the two pressure relief portions being located on either side of the second pressure relief groove, respectively.
The pressure relief mechanism of claim 2, wherein two pressure relief portions are symmetrically disposed on both sides of the second pressure relief groove.
The pressure relief mechanism according to claim 2 or 3, wherein a distance between the first pressure relief groove and the third pressure relief groove gradually increases in a direction from the second pressure relief groove to both ends of the first pressure relief groove.
The pressure relief mechanism of claim 1, wherein the first pressure relief slot, the second pressure relief slot, and the third pressure relief slot together define one of the pressure relief portions, the first pressure relief slot, the second pressure relief slot, and the third pressure relief slot being located at three edges of the pressure relief portion that are different orientations and adjacent, respectively.
The pressure relief mechanism of any of claims 1-5, wherein the second pressure relief groove has a first end facing the first pressure relief groove, a gap between the first end and the first pressure relief groove being no more than one third of a distance between the first pressure relief groove and the third pressure relief groove; and/or

The second pressure relief groove has a second end facing the third pressure relief groove, and a gap between the second end and the third pressure relief groove is not greater than one third of a distance between the first pressure relief groove and the third pressure relief groove.
The pressure relief mechanism of claim 1, 2, 3, 5, or 6, wherein the first pressure relief slot is parallel to the third pressure relief slot and perpendicular to the second pressure relief slot.
The pressure relief mechanism of any one of claims 1-7, wherein the first pressure relief groove comprises a plurality of first groove portions that are disposed sequentially along a depth direction of the first pressure relief groove, and wherein a width of the plurality of first groove portions gradually decreases along the depth direction of the first pressure relief groove.
The pressure relief mechanism of any one of claims 1-8, wherein the second pressure relief groove comprises a plurality of second groove portions that are disposed sequentially along a depth direction of the second pressure relief groove, and wherein a width of the plurality of second groove portions gradually decreases along the depth direction of the second pressure relief groove.
The pressure relief mechanism according to any one of claims 1-9, wherein the third pressure relief groove comprises a plurality of third groove portions, the plurality of third groove portions being disposed sequentially along a depth direction of the third pressure relief groove, a width of the plurality of third groove portions gradually decreasing along the depth direction of the third pressure relief groove.
The pressure relief mechanism according to any one of claims 1-10 wherein said pressure relief body defines a receiving space therein for receiving an electrode assembly, said pressure relief body having a plurality of walls that collectively define said receiving space, at least one of said walls being provided with said pressure relief structure.
A battery cell comprising the pressure relief mechanism of any one of claims 1-11.
A battery, comprising:

the battery cell of claim 12; and

and the box body is used for accommodating the battery cells.
A powered device comprising the battery of claim 13.
A method of manufacturing a pressure relief mechanism, the method comprising:

providing a pressure relief body;

processing a pressure relief structure on the pressure relief body;

the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value so as to relieve the pressure inside the battery cell; the second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.
A manufacturing apparatus for a pressure relief mechanism, the manufacturing apparatus comprising:

the providing device is used for providing the pressure relief body;

the processing device is used for processing the pressure relief structure on the pressure relief body;

the pressure relief structure comprises a first pressure relief groove, a second pressure relief groove and a third pressure relief groove which are arranged on the pressure relief body and located in different directions, wherein the first pressure relief groove, the second pressure relief groove and the third pressure relief groove jointly define a pressure relief part, and the pressure relief part is configured to be opened by taking the first pressure relief groove, the second pressure relief groove and the third pressure relief groove as boundaries when the pressure or the temperature inside the battery cell reaches a threshold value so as to relieve the pressure inside the battery cell; the second pressure relief groove is located between the first pressure relief groove and the third pressure relief groove and is not intersected with the first pressure relief groove and the third pressure relief groove.