CN115939656A - Shell, battery monomer, battery and consumer - Google Patents

Abstract

The application provides a shell, battery monomer, battery and consumer relates to the battery field. The shell comprises a plurality of wall parts, and the wall parts surround to form a containing space for containing an electrode assembly of the battery cell. Wherein at least two of the wall portions are formed with a weak portion configured to be ruptured when the battery cell is decompressed to discharge a pressure inside the battery cell. Be formed with the weak part on two at least wall portions of this shell, when the single cell pressure release, the weak part that is located on different wall portions all splits for gas in the single cell can be followed different position discharge single cell, realizes diversified pressure release simultaneously, avoids concentrating the pressure release from a position, thereby reduces the risk of burning through the inside protection architecture of battery, promotes the security of battery.

Description

Shell, battery monomer, battery and consumer

Technical Field

The application relates to the field of batteries, in particular to a shell, a battery monomer, a battery and electric equipment.

Background

Batteries are widely used in new energy fields, such as electric vehicles, new energy vehicles and the like, and the new energy vehicles and the electric vehicles become new development trends of the automobile industry. The development of battery technology needs to consider various design factors, such as battery life, energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, the safety of the battery needs to be considered. However, the safety of the current batteries is poor.

Disclosure of Invention

An object of the embodiments of the present application is to provide a housing, a battery cell, a battery and an electric device, which aim to improve the problem of poor safety of the battery in the related art.

In a first aspect, embodiments of the present application provide a case, where the case includes a plurality of wall portions that surround to form an accommodating space for accommodating an electrode assembly of the battery cell; wherein at least two of the wall portions are formed with a weak portion configured to be ruptured when the battery cell is decompressed to discharge a pressure inside the battery cell.

In above-mentioned technical scheme, be formed with the weak part on two at least wall portions of this shell, when the single cell pressure release, the weak part that is located on different wall portions all splits for gas in the single cell can be followed different position discharge single cell, realizes diversified pressure release simultaneously, avoids concentrating the pressure release from a position, thereby reduces the risk of burning through the inside protection architecture of battery, promotes the security of battery.

As an alternative to the embodiment of the present application, at least one end of the weak portion extends to an edge of the wall portion.

In the above technical solution, by extending at least one end of the weak portion to the edge of the wall portion, when the battery cell is depressurized, the weak portion may first crack from the end extending to the edge of the wall portion, and gradually crack the entire weak portion along the extending direction of the weak portion (crack like peeling a banana), so that the weak portion cracks a large opening quickly, and the battery cell is depressurized quickly.

As an alternative solution to the embodiment of the present application, two ends of the weak portion respectively extend to two edges of the wall portion.

In above-mentioned technical scheme, through making the both ends of weak part extend to two edges of wall portion respectively, when the battery cell pressure release, the weak part can begin to split from both ends at first to make whole weak part split fast (split like peeling banana) along the extending direction of weak part, with the great opening that supplies the inside gas outflow of battery cell, realize the quick pressure release of battery cell.

As an alternative to the embodiment of the present application, two ends of the weak portion respectively extend to two opposite edges of the wall portion.

In above-mentioned technical scheme, through making the both ends of weak part extend to two relative edges of wall portion respectively, when the battery cell pressure release, the weak part can begin to split from both ends at first to make whole weak part split rapidly (split like peeling off the banana) along the extending direction of weak part, with the great opening that supplies the inside gas outflow of battery cell, realize the quick pressure release of battery cell.

As an alternative to the embodiment of the present application, the wall portion has a first edge and a second edge opposite to each other along a first direction, at least one of the wall portions is provided with a plurality of the weak portions, and the plurality of the weak portions are arranged at intervals along the first direction.

In above-mentioned technical scheme, through setting up a plurality of weak parts along first direction interval, be favorable to guaranteeing the intensity of wall portion when battery monomer normal use. Simultaneously when the battery monomer pressure release, the wall part splits from the position of weak part at first, and the part between two weak parts also can be torn by the air current to open great supply battery monomer inside gas outflow's opening, realize the free quick pressure release of battery.

As an optional solution of the embodiment of the present application, along the first direction, the two weak portions at two ends extend to the first edge and the second edge respectively.

In the technical scheme, the two weak parts located at the two ends along the first direction respectively extend to the first edge and the second edge, when the single battery is subjected to pressure relief, the two weak parts located at the two ends along the first direction can be cracked from the two ends firstly, and the parts between the plurality of weak parts and the two adjacent weak parts are cracked rapidly along the first direction (cracked like banana peeling), so that the single battery is subjected to rapid pressure relief.

As an alternative to the embodiment of the present application, the weak portion is a closed structure extending along a closed track.

In the technical scheme, the weak part is arranged to be a closed structure extending along the closed track, so that the weak part is cracked along the weak part during pressure relief, and an opening for gas to pass through is formed.

As an alternative to the embodiment of the present application, the weak portion is a non-closed structure extending along a non-closed track.

In above-mentioned technical scheme, there is the distance at the both ends of non-closed orbit, also has the distance between the both ends of the weak part that extends along non-closed orbit, like this, when the free pressure release of battery, the axis of rotation can be regarded as to the part between the both ends of weak part, and the part that is enclosed by the weak part opens around this axis of rotation upset and forms the opening, is favorable to promoting to open efficiency, realizes the free quick pressure release of battery, is favorable to improving the free security of battery.

As an optional solution of the embodiment of the present application, the plurality of wall portions include a bottom wall and a plurality of side walls, the plurality of side walls are arranged around the bottom wall, and the at least two side walls are formed with the weak portion.

In the above technical solution, the side wall is provided with the weak portion, compared with the weak portion arranged on the bottom wall, when the battery cell is subjected to pressure relief, the pressure relief can be performed by cracking more conveniently (the bottom wall supports the whole battery cell, and the weak portion is arranged on the bottom wall, so that the bottom wall is easily blocked and is not easy to crack. In addition, the lateral wall is compared in the diapire, is convenient for more set up heat transfer structure, cools off and protects.

As an alternative to the embodiment of the present application, each of the side walls is provided with the weak portion.

In above-mentioned technical scheme, all set up the weak part through all on every lateral wall, be convenient for carry out the pressure release from a plurality of azimuths. Avoid concentrating the pressure release from an azimuth to reduce the risk of burning through the inside protection architecture of battery, promote the security of battery.

As an alternative solution to the embodiment of the present application, the side wall has a first edge and a second edge opposite to each other, the first edge is located at a position where the side wall is connected to the bottom wall, and two ends of the weak portion extend to the first edge and the second edge respectively.

In above-mentioned technical scheme, through the both ends that make the weak part extend to first edge and second edge respectively, when the battery cell pressure release, the weak part can begin to split at first from both ends to make whole weak part split fast (tearing like peeling banana along the extending direction of weak part), with the opening that provides great confession battery cell inside gas outflow, realize the free quick pressure release of battery.

As an alternative to the embodiment of the present application, an extending direction of the weak portion is perpendicular to an extending direction of the first edge.

Among the above-mentioned technical scheme, the direction of the extending direction of weak part along the first edge of perpendicular to extends, is favorable to splitting apart fast when the single pressure release of battery, realizes the single quick pressure release of battery.

As an alternative solution to the embodiment of the present application, the weak portion is disposed at a central position of the side wall along an extending direction of the first edge.

In above-mentioned technical scheme, the intensity that the lateral wall is close to the position of edge is higher, and the position intensity that is close to the center is lower, consequently through setting up the weak part in the central point that the extending direction of lateral wall edge was put for the weak part splits easily when the battery monomer pressure release.

As an alternative solution to the embodiment of the present application, the bottom wall and the plurality of side walls are integrally formed.

In the technical scheme, the bottom wall and the side wall are integrally formed, so that the overall strength of the bottom wall and the side wall is high, and a good protection effect on the electrode assembly can be achieved.

As an alternative to the embodiment of the present application, the weak portion is formed by providing a score groove on the wall portion.

In the technical scheme, the mark carving groove is formed in the weak part to form the weak part, so that the method is simple and convenient, easy to process and low in production cost.

As an optional technical solution of the embodiment of the present application, the scored groove is a linear groove.

In the technical scheme, the straight line groove is formed in the wall part to form the straight line-shaped weak part, so that the weak part is conveniently cracked along a straight line track when the battery is decompressed, the quick decompression is realized, and the safety of the battery monomer is improved.

As an alternative to the embodiment of the present application, the weak portion is formed by annealing the wall portion.

In the above technical solution, annealing treatment is performed on a local portion of the wall portion, so as to refine material crystal grains of the local portion of the wall portion, release internal material stress of the local portion of the wall portion, and soften the wall portion at the same time, so as to form a weak portion.

In a second aspect, embodiments of the present application further provide a battery cell, where the battery cell includes the casing and an electrode assembly, and the electrode assembly is accommodated in the casing.

In a third aspect, an embodiment of the present application further provides a battery, where the battery includes a box body and the above battery cell, and the battery cell is accommodated in the box body.

In a fourth aspect, an embodiment of the present application further provides an electric device, where the electric device includes the above battery, and the battery is used to provide electric energy for the electric device.

Drawings

To more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

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 accordance with some embodiments of the present application;

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

FIG. 4 is a schematic structural view of an enclosure (both ends of the weakened portion extend to both edges of the wall portion, respectively) provided in some embodiments of the present application;

FIG. 5 is a schematic structural diagram of a housing according to yet another embodiment of the present application;

FIG. 6 is a schematic structural view of an enclosure (one end of the weakened portion extending to the edge of the wall portion) provided by some embodiments of the present application;

FIG. 7 is a schematic view of a housing (the weakened portion does not extend to the edge of the wall portion) provided by some embodiments of the present application;

FIG. 8 is a schematic view of a housing (one wall portion provided with a plurality of weakened portions) according to some embodiments of the present disclosure;

FIG. 9 is a schematic structural view of an enclosure (two weakened portions at two ends extending to a first edge and a second edge, respectively) according to some embodiments of the present disclosure;

FIG. 10 is a schematic structural view of an enclosure (the weakened portion is a closed structure extending along a closed path) provided by some embodiments of the present application;

fig. 11 is a schematic structural diagram of an enclosure (the weak portion is a non-closed structure extending along a non-closed track) provided in some embodiments of the present application.

Icon: 10-a box body; 11-a first part; 12-a second part; 20-a battery cell; 21-a housing; 211-a wall portion; 2111-weaknesses; 212-side walls; 2121-a first edge; 2122-a second edge; 213-a housing; 214-an end cap; 22-an electrode assembly; 100-a battery; 200-a controller; 300-a motor; 1000-vehicle.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present 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 in the present application 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. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not 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 can be included in at least one embodiment of the specification. 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.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "attached" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected 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 as appropriate.

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

In the embodiments of the present application, like reference numerals denote like parts, and a detailed description of the same parts is omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width and other dimensions of the various components in the embodiments of the present application and the overall thickness, length, width and other dimensions of the integrated device shown in the drawings are only exemplary and should not constitute any limitation to the present application.

The appearances of "a plurality" in this application are intended to mean more than two (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 embodiments of the present application. The battery cell 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 are generally divided into three types in an encapsulation manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are also not limited in the embodiment of the application.

Reference to a battery in embodiments 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, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane. The battery cell mainly depends on metal ions moving between the positive plate and the negative plate to work. The positive plate comprises a positive current collector and a positive active substance layer, wherein the positive active substance layer is coated on the surface of the positive current collector, the positive current collector which is not coated with the positive active substance layer protrudes out of the positive current collector which is coated with the positive active substance layer, and the positive current collector which is not coated with the positive active substance layer is used as a positive 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 pole piece includes negative pole mass flow body and negative pole active substance layer, and the surface of negative pole mass flow body is scribbled to the negative pole active substance layer, and the negative pole mass flow body protrusion in the negative pole mass flow body of having scribbled the negative pole active substance layer of not scribbling the negative pole active substance layer, and the negative pole mass flow body of not scribbling the negative pole active substance layer is as negative pole ear. 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 fuse is not fused when a large current is passed, a plurality of positive electrode tabs are stacked, and a plurality of negative electrode tabs are stacked. The material of the isolation film may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

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

The development of battery technology requires consideration of various design factors, such as energy density, cycle life, discharge capacity, charge/discharge rate, and other performance parameters, as well as battery safety.

For the single battery, in order to guarantee the safety of the single battery, a pressure relief structure can be arranged on the end cover of the single battery, for example, a weak part is arranged on the end cover, and when the internal pressure of the single battery reaches the detonation pressure, the weak part is opened to release the internal pressure of the single battery so as to reduce the risks of explosion and ignition of the single battery.

The inventor has noticed that in a chemical system with high gas generation (for example, the positive electrode active material comprises lithium nickel cobalt manganese oxide, the weight of nickel element in the lithium nickel cobalt manganese oxide is G1, the sum of the weights of nickel element, cobalt element and manganese element is G2, the value of G1/G2 is denoted as M, M satisfies 0.65 ≦ M ≦ 1), the single battery is severely decompressed, and the gas in the single battery is decompressed through the decompression structure arranged on the end cap, that is, the decompression structure on the end cap is decompressed intensively from one direction. Because the pressure relief is severe and the temperature of the gas is high, the protective structure in the box body of the battery can be burnt through, for example, a protective plate opposite to the pressure relief structure is burnt through, so that flame is exposed, explosion can be seriously caused, and the safety of the battery is poor.

In view of this, the present embodiment provides a housing, which includes a plurality of wall portions, and the plurality of wall portions surround to form an accommodating space for accommodating an electrode assembly of a battery cell. Wherein at least two of the wall portions are formed with a weak portion configured to be ruptured when the battery cell is decompressed to discharge a pressure inside the battery cell.

Be formed with the weak part on two at least wall portions of this shell, when the single cell pressure release, the weak part that is located on different wall portions all splits for gas in the single cell can be followed different position discharge single cell, realizes diversified pressure release simultaneously, avoids concentrating the pressure release from a position, thereby reduces the risk of burning through the inside protection architecture of battery, promotes the security of battery.

The technical scheme described in the embodiment of the application is suitable for the battery and the 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. Spacecraft include aircraft, rockets, space shuttles, spacecraft, and the like; the electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above-mentioned electric devices.

For convenience of description, the following embodiments will be described by taking an electric device as the vehicle 1000.

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

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

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

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

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

Referring to fig. 3, fig. 3 is an exploded view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery 100. As shown in fig. 3, the battery cell 20 includes a case 21 and an electrode assembly 22.

The case 21 has a receiving space in which the electrode assembly 22 is received, and the electrode assembly 22 is received in the receiving space.

The electrode assembly 22 is a component of the battery cell 20 in which electrochemical reactions occur. One or more electrode assemblies 22 may be contained within the housing 21. The electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive and negative electrode sheets having the active material constitute the body portion of the electrode assembly 22, and the portions of the positive and negative electrode sheets having no active material each constitute a tab. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or at both ends of the main body portion, respectively. During the charge and discharge of the battery 100, the positive and negative active materials react with the electrolyte, and the tabs are connected to the electrode terminals to form a current loop.

Referring to fig. 4 and 5, fig. 4 is a schematic structural view of the outer shell 21 (two ends of the weak portion 2111 extend to two edges of the wall portion 211, respectively) according to some embodiments of the present disclosure. Fig. 5 is a schematic structural diagram of a housing 21 according to another embodiment of the present application. The embodiment of the application provides a shell 21, and the shell 21 comprises a plurality of wall parts 211, and the plurality of wall parts 211 surround to form a containing space for containing an electrode assembly 22 of a battery cell 20. Wherein at least two of the wall portions 211 are formed with weak portions 2111, the weak portions 2111 being configured to be ruptured when the battery cell 20 is depressurized to relieve the pressure inside the battery cell 20.

The case 21 is a case structure for accommodating the electrode assembly 22 of the battery cell 20. The housing 21 may be a shell 213. The housing 21 may also include a shell 213 and an end cap 214. In an actual production process, the housing 213 and the end cap 214 are separately provided, and the housing 213 and the end cap 214 are assembled together in a subsequent process. Therefore, the separate housing 213 and the assembly structure of the housing 213 and the end cap 214 should be included in the protection scope of the present application.

The end cap 214 is a member covering the opening of the case 213 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 214 may be adapted to the shape of the housing 213 to fit the housing 213. Alternatively, the end cap 214 may be made of a material (e.g., an aluminum alloy) having certain hardness and strength, so that the end cap 214 is not easily deformed when being extruded and collided, and thus the battery cell 20 may have higher structural strength and improved safety performance. The end cap 214 may be provided with functional components such as electrode terminals (not shown in the drawings). The electrode terminals may be used to electrically connect with the electrode assembly 22 for outputting or inputting electric power of the battery cell 20. The material of the end cap 214 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this application. In some embodiments, insulation may also be provided on the inside of the end cap 214, which may be used to isolate the electrical connection components within the housing 213 from the end cap 214 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The case 213 is an assembly for mating with the end cap 214 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to house the electrode assembly 22, electrolyte, and other components. The housing 213 and the end cap 214 may be separate components, and an opening may be provided in the housing 213 to form the internal environment of the battery cell 20 by covering the opening with the end cap 214. Without limitation, the end cap 214 and the housing 213 may be integrated, and specifically, the end cap 214 and the housing 213 may form a common connecting surface before other components are inserted into the housing, and when it is required to seal the inside of the housing 213, the end cap 214 covers the housing 213. The housing 213 may be 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 case 213 may be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 213 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment.

The case 21 includes a plurality of wall portions 211, and the plurality of wall portions 211 surround to form a housing space for housing the electrode assembly 22. The plurality of wall portions 211 may be entirely provided from the case 213, or the plurality of wall portions 211 may be provided from the case 213 and the end cover 214. For example, the end cap 214 may alone form one wall portion 211. The housing 213 may include five wall portions 211, the five wall portions 211 enclosing a receiving space having an opening at one end, and one wall portion 211 formed of the end cap 214 for closing the opening.

The plurality of wall portions 211 are located in different orientations, and for example, the plurality of wall portions 211 may be located above, below, left, right, front, rear, and the like, respectively, with respect to the center position of the housing 21 as a reference point.

The weak portion 2111 is a portion of the wall portion 211 with a lower strength, and when the internal pressure of the battery cell 20 reaches the initiation pressure, the weak portion 2111 opens under the pressure to release the internal pressure of the battery cell 20, so as to reduce the risk of explosion and fire of the battery cell 20.

At least two wall portions 211 of this shell 21 are formed with weak part 2111, and when battery cell 20 pressure release, the weak part 2111 that is located on different wall portions 211 all splits for gas in the battery cell 20 can be followed different position discharge battery cell 20, realizes diversified pressure release simultaneously, avoids concentrating the pressure release from a position, thereby reduces the risk of burning through battery 100 internal protection structure, promotes battery 100's security.

In some embodiments, referring to fig. 4 and 5, at least one end of the weakened portion 2111 extends to the edge of the wall portion 211.

The weak portion 2111 may extend along a certain trajectory, and the end point of the trajectory is the end of the weak portion 2111.

Taking the wall 211 as an example of a rectangular plate-shaped structure, in a certain view, for example, a front view, the wall 211 is rectangular. The weakened portion 2111 is located inside the rectangle and has at least one end extending to the long or short side of the rectangle.

By extending at least one end of the weak portion 2111 to the edge of the wall portion 211, when the battery cell 20 is depressurized, the weak portion 2111 may be first ruptured from the end extending to the edge of the wall portion 211, and the entire weak portion 2111 is gradually ruptured along the extending direction of the weak portion 2111 (ruptured like banana peeling), facilitating the weak portion 2111 to be rapidly ruptured through a large opening, thereby achieving rapid depressurization of the battery cell 20.

In some embodiments, both ends of the weak portion 2111 extend to both edges of the wall portion 211, respectively.

The positional relationship between the two edges is arbitrary, and for example, the two edges may be arranged oppositely or adjacently.

By extending both ends of the weak portion 2111 to both edges of the wall portion 211, respectively, when the battery cell 20 is depressurized, the weak portion 2111 may be first ruptured from both ends, and the entire weak portion 2111 may be rapidly ruptured along the extending direction of the weak portion 2111 (ruptured like banana peeling) to provide a large opening for the gas inside the battery cell 20 to flow out, thereby achieving rapid depressurization of the battery cell 20.

Referring to fig. 4 and 5, in some embodiments, both ends of the weak portion 2111 extend to two opposite edges of the wall portion 211.

Taking the wall portion 211 as an example of a rectangular plate-shaped structure, in a certain view, for example, a front view, the wall portion 211 is rectangular. The weak portion 2111 is located inside the rectangle and both ends extend to both long sides of the rectangle or both short sides of the rectangle, respectively.

By extending both ends of the weak portion 2111 to the two opposite edges of the wall portion 211, respectively, when the battery cell 20 is depressurized, the weak portion 2111 may be first ruptured from both ends, and the entire weak portion 2111 may be rapidly ruptured (ruptured like peeling banana) along the extending direction of the weak portion 2111 to provide a large opening for the gas inside the battery cell 20 to flow out, thereby achieving rapid depressurization of the battery cell 20.

In other embodiments, both ends of the weak portion 2111 extend to the adjacent two edges of the wall portion 211, respectively. Taking the wall portion 211 as an example of a rectangular plate-shaped structure, in a certain view, for example, a front view, the wall portion 211 is rectangular. The weak portion 2111 is located inside the rectangle and both ends extend to the long side and the short side of the rectangle, respectively.

Referring to fig. 6, fig. 6 is a schematic structural diagram of the housing 21 (one end of the weak portion 2111 extends to an edge of the wall portion 211) according to some embodiments of the present disclosure. In some embodiments, one end of the weakened portion 2111 extends to the edge of the wall portion 211. Taking the wall portion 211 as an example of a rectangular plate-shaped structure, in a certain view, for example, a front view, the wall portion 211 is rectangular. The weak portion 2111 is located inside the rectangle and has one end extending to the long or short side of the rectangle and the other end spaced from the long or short side of the rectangle.

Referring to fig. 7, fig. 7 is a schematic structural diagram of the outer shell 21 (the weak portion 2111 does not extend to the edge of the wall portion 211) according to some embodiments of the present disclosure. In some embodiments, the weaknesses 2111 do not extend to the edge of the wall 211. Taking the wall portion 211 as an example of a rectangular plate-shaped structure, in a certain view, for example, a front view, the wall portion 211 is rectangular. The weak portion 2111 is located inside the rectangle with a space between the long side and the short side of the rectangle.

Referring to fig. 8, fig. 8 is a schematic structural diagram of a housing 21 (a wall 211 is provided with a plurality of weak portions 2111) according to some embodiments of the present disclosure. In some embodiments, the wall 211 has a first edge 2121 and a second edge 2122 opposite along the first direction. At least one wall portion 211 is provided with a plurality of weak portions 2111, the plurality of weak portions 2111 being provided at intervals in the first direction.

The first edge 2121 and the second edge 2122 are two edges of the wall portion 211 opposing in the first direction. Here, the first edge 2121 and the second edge 2122 do not particularly indicate which edge, as long as the first edge 2121 and the second edge 2122 are oppositely disposed. Taking the wall 211 as an example of a rectangular plate-shaped structure, the first edge 2121 and the second edge 2122 may be a left edge and a right edge of the wall 211, respectively, in which case the first direction is a left-right direction. The first edge 2121 and the second edge 2122 can also be an upper edge and a lower edge, respectively, of the wall 211, in which case the first direction is the up-down direction.

A plurality of weak portions 2111 are provided in one wall portion 211, and the plurality of weak portions 2111 are provided at intervals in the first direction. In the embodiment shown in fig. 8, the weak portion 2111 is a straight line structure. The plurality of weak portions 2111 each extend along the first direction, and the plurality of weak portions 2111 are provided at intervals in the first direction.

By disposing the plurality of weak portions 2111 at intervals in the first direction, it is advantageous to ensure the strength of the wall portion 211 when the battery cell 20 is used normally. Meanwhile, when the single battery 20 is decompressed, the wall part 211 is firstly split from the positions of the weak parts 2111, and the part between the two weak parts 2111 can be also torn by airflow, so that a large opening for the gas in the single battery 20 to flow out is opened, and the single battery 20 is decompressed quickly.

Referring to fig. 9, fig. 9 is a schematic structural diagram of the housing 21 (two weak portions 2111 at two ends extend to the first edge 2121 and the second edge 2122, respectively) according to some embodiments of the present disclosure. In some embodiments, two weaknesses 2111 at both ends extend in the first direction to a first edge 2121 and a second edge 2122, respectively.

In the embodiment shown in fig. 9, 5 weak portions 2111 are provided in one wall portion 211. The 5 weak portions 2111 are arranged at intervals in the first direction. At this time, the first direction is an up-down direction, and the first edge 2121 and the second edge 2122 are an upper edge and a lower edge, respectively. Wherein the uppermost one of the weaknesses 2111 extends to the upper edge and the lowermost one of the weaknesses 2111 extends to the lower edge, i.e. in the first direction, the two weaknesses 2111 at both ends extend to the first edge 2121 and the second edge 2122, respectively.

When the two weak portions 2111 at both ends in the first direction are extended to the first edge 2121 and the second edge 2122, respectively, when the single battery cell 20 is depressurized, the two weak portions 2111 at both ends in the first direction may be ruptured from both ends first, and a portion between the plurality of weak portions 2111 and the adjacent two weak portions 2111 is rapidly ruptured in the first direction (ruptured like banana), thereby achieving rapid depressurization of the single battery cell 20.

Referring to fig. 10, fig. 10 is a schematic structural diagram of the housing 21 (the weak portion 2111 is a closed structure extending along a closed track) according to some embodiments of the present application. In some embodiments, the weaknesses 2111 are closed structures extending along closed trajectories.

"closed trajectory" means a trajectory having ends joined together. The closed track may be a circular track, an elliptical track, a polygonal track, or the like. The weak portion 2111 extends along a closed trajectory, and therefore, the weak portion 2111 may also have a circular structure, an elliptical structure, a polygonal structure, or the like.

The weakened portion 2111 is provided as a closed structure extending along a closed trajectory so as to rupture along the weakened portion 2111 upon pressure relief, forming an opening for passage of gas.

Referring to fig. 11, fig. 11 is a schematic structural diagram of a housing 21 (the weak portion 2111 is an unclosed structure extending along an unclosed track) according to some embodiments of the present application. In some embodiments, the weaknesses 2111 are non-enclosed structures extending along non-enclosed trajectories.

The non-closed tracks have a space between their ends. The non-closed trajectory may be a U-shaped trajectory, a C-shaped trajectory, a circular arc trajectory, a parabolic trajectory, or the like. The weak portion 2111 extends along a non-closed trajectory having a distance between both ends, and therefore, the weak portion 2111 may have a U-shaped structure, a C-shaped structure, an arc structure, a parabolic structure, or the like.

There is a distance at both ends of the non-closed track, that is, there is a distance between both ends of the weak portion 2111 extending along the non-closed track, so that, when the single battery 20 is depressurized, a portion between both ends of the weak portion 2111 can be used as a rotation axis, and a portion surrounded by the weak portion 2111 is turned over around the rotation axis and opened to form an opening, which is beneficial to improving the opening efficiency, realizing the rapid depressurization of the single battery 20, and improving the safety of the single battery 20.

Referring to fig. 4 to 11, in some embodiments, the plurality of wall portions 211 includes a bottom wall and a plurality of side walls 212, and the plurality of side walls 212 are disposed around the bottom wall. At least two of the side walls 212 are formed with weaknesses 2111.

The side wall 212 is a wall portion 211 parallel to the height direction of the battery cell 20 among the plurality of wall portions 211. The bottom wall is a wall portion 211 perpendicular to the height direction of the battery cell 20 among the plurality of wall portions 211. The bottom wall is generally located at the bottom of the battery cell 20. Generally, the bottom wall is a wall portion 211 that mainly supports the electrode assembly 22 of the battery cell 20. The side wall 212 is connected to the bottom wall and surrounds the bottom wall to form an accommodating space together with the bottom wall.

Providing the weak portion 2111 on the side wall 212 enables more convenient rupture for pressure release when the battery cell 20 is depressurized than providing the weak portion 2111 on the bottom wall (the bottom wall is easily blocked and not easily ruptured because the bottom wall supports the entire battery cell 20, and the weak portion 2111 is provided on the bottom wall). In addition, the side wall 212 is more convenient for arranging a heat exchange structure for cooling and protection than the bottom wall.

In some embodiments, each sidewall 212 is provided with a weakened portion 2111.

As shown in the drawing, the housing 21 has a rectangular parallelepiped structure having 4 side walls 212 and 1 bottom wall, and weak portions 2111 are provided on all of the 4 side walls 212.

Pressure relief from multiple orientations is facilitated by providing a weakened portion 2111 on each side wall 212. Avoid concentrating the pressure release from an azimuth to reduce the risk of burning through the inside protection architecture of battery 100, promote the security of battery 100.

In some embodiments, the sidewall 212 has opposing first and second edges 2121 and 2122, the first edge 2121 being located where the sidewall 212 joins the bottom wall. Both ends of the weak portion 2111 extend to a first edge 2121 and a second edge 2122, respectively.

The first edge 2121 is specifically the edge of the sidewall 212 that connects to the bottom wall. The second edge 2122 is the opposite edge of the sidewall 212 from the first edge 2121. As shown in fig. 4, the first edge 2121 is a lower edge of the sidewall 212 and the second edge 2122 is an upper edge of the sidewall 212. Both ends of the weak portion 2111 extend to the lower edge and the lower edge, respectively.

By extending both ends of the weak portion 2111 to the first edge 2121 and the second edge 2122, respectively, when the battery cell 20 is depressurized, the weak portion 2111 may be first ruptured from both ends, and the entire weak portion 2111 may be rapidly ruptured along the extending direction of the weak portion 2111 (ruptured like banana peeling) to provide a large opening for the gas inside the battery cell 20 to flow out, thereby achieving rapid depressurization of the battery cell 20.

In some embodiments, the direction of extension of the weakpoint 2111 is perpendicular to the direction of extension of the first edge 2121.

As shown in fig. 4, the extending direction of the first edge 2121 is the left-right direction. The extending direction of the weak portion 2111 is perpendicular to the left-right direction. The weak portion 2111 extends in the up-down direction.

The weak portion 2111 extends in a direction perpendicular to the extending direction of the first edge 2121, and is advantageous to be rapidly cracked when the battery cell 20 is decompressed, so that the battery cell 20 is rapidly decompressed.

In some embodiments, the weakened portion 2111 is provided at a central position of the side wall 212 in the extending direction of the first edge 2121.

"the weak portion 2111 is provided at the center position of the side wall 212 in the extending direction of the first edge 2121" may also be understood as meaning that the orthographic projection of the weak portion 2111 at the first edge 2121 is located at the center position of the first edge 2121.

The side wall 212 has a higher strength near the edge and a lower strength near the center, so that the weak portion 2111 is easily broken when the battery cell 20 is depressurized by providing the weak portion 2111 at the center of the side wall 212 in the extending direction of the first edge 2121.

In some embodiments, the bottom wall and the plurality of side walls 212 are integrally formed.

The bottom wall and the plurality of side walls 212 may be integrally formed by stamping or casting.

The bottom wall and the side wall 212 are integrally formed, so that the overall strength of the bottom wall and the side wall 212 is high, and the electrode assembly 22 can be well protected.

In some embodiments, the weakened portion 2111 is formed by providing a score groove in the wall portion 211.

The score groove may be a groove body recessed from the surface of the wall portion 211 in the thickness direction of the wall portion 211. The notch groove may be provided on the surface of the wall portion 211 facing the electrode assembly 22, or may be provided on the surface of the wall portion 211 facing away from the electrode assembly 22. Taking the wall portion 211 as an example of a rectangular flat plate structure, the wall portion 211 has a first surface and a second surface opposite to each other in a thickness direction thereof, the first surface facing the electrode assembly 22, and the second surface facing away from the electrode assembly 22. The notch groove may be provided on the first surface of the wall portion 211, or may be provided on the second surface of the wall portion 211.

The cross section of the scored groove may be V-shaped, trapezoidal, semicircular, etc., and the present application is not limited thereto.

The weak portion 2111 is formed by arranging the mark engraving groove on the weak portion 2111, so that the method is simple, convenient, easy to process and low in production cost.

In some embodiments, the scored groove is a linear groove.

The linear groove is a groove body structure extending along a linear track.

The straight line groove is formed in the wall 211 to form the straight line weak portion 2111, so that the weak portion 2111 is conveniently cracked along a straight line track when the battery 100 is depressurized, and rapid depressurization is realized to improve the safety of the battery cell 20.

In some embodiments, the weakened portions 2111 are formed by annealing the wall portion 211.

Annealing is a heat treatment process for metals, which refers to slowly heating the metal to a certain temperature, holding for a sufficient time, and then cooling at a suitable rate. The method aims to reduce hardness, improve machinability, reduce residual stress, stabilize size, reduce deformation and crack tendency, refine grains, adjust tissue and eliminate tissue defects. For example, the wall portion 211 may be laser-welded, and high temperature generated by the laser welding may act on the wall portion 211 to anneal the wall portion 211 to form the weak portion 2111 at the welding position. For another example, wall portion 211 may be annealed by baking wall portion 211 to form weak portion 2111 at the baking position.

Annealing is locally applied to the wall portion 211 to refine crystal grains of the material of the local portion of the wall portion 211, to relieve internal stress of the material of the local portion of the wall portion 211, and to soften the wall portion 211 to form the weak portion 2111.

The embodiment of the present application further provides a battery cell 20, where the battery cell 20 includes the above-mentioned case 21 and an electrode assembly 22, and the electrode assembly 22 is accommodated in the case 21.

The embodiment of the present application further provides a battery 100, where the battery 100 includes a case 10 and the battery cell 20, and the battery cell 20 is accommodated in the case 10.

The embodiment of the present application further provides an electric device, where the electric device includes the above battery 100, and the battery 100 is used for providing electric energy for the electric device.

Please refer to fig. 4-5 according to some embodiments of the present application.

The embodiment of the application provides a shell 21, and the shell 21 includes a plurality of wall parts 211, and a plurality of wall parts 211 enclose to form a receiving space, and the receiving space is used for receiving an electrode assembly 22 of a battery cell 20. Wherein at least two of the wall portions 211 are formed with weak portions 2111, the weak portions 2111 being configured to be ruptured when the battery cell 20 is depressurized to relieve the pressure inside the battery cell 20. At least two wall portions 211 of this shell 21 are formed with weak part 2111, and when battery cell 20 pressure release, the weak part 2111 that is located on different wall portions 211 all splits for gas in the battery cell 20 can be followed different position discharge battery cell 20, realizes diversified pressure release simultaneously, avoids concentrating the pressure release from a position, thereby reduces the risk of burning through battery 100 internal protection structure, promotes battery 100's security.

The plurality of wall portions 211 include a bottom wall and a plurality of side walls 212, the plurality of side walls 212 are provided around the bottom wall, and at least two side walls 212 are formed with weak portions 2111. Providing the weak portion 2111 on the side wall 212 enables more convenient rupture for pressure release when the battery cell 20 is depressurized than providing the weak portion 2111 on the bottom wall (the bottom wall is easily blocked and not easily ruptured because the bottom wall supports the entire battery cell 20, and the weak portion 2111 is provided on the bottom wall). In addition, the side wall 212 is more convenient for arranging a heat exchange structure for cooling and protection than the bottom wall.

The side wall 212 has opposite first and second edges 2121 and 2122, the first edge 2121 being located where the side wall 212 joins the bottom wall. Both ends of the weak portion 2111 extend to a first edge 2121 and a second edge 2122, respectively. By extending both ends of the weak portion 2111 to the first edge 2121 and the second edge 2122, respectively, when the battery cell 20 is depressurized, the weak portion 2111 may be first ruptured from both ends, and the entire weak portion 2111 may be rapidly ruptured along the extending direction of the weak portion 2111 (ruptured like banana peeling) to provide a large opening for the gas inside the battery cell 20 to flow out, thereby achieving rapid depressurization of the battery cell 20.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (20)

1. A housing for a battery cell, comprising:

a plurality of wall portions enclosing to form an accommodating space for accommodating an electrode assembly of the battery cell;

wherein at least two of the wall portions are formed with a weak portion configured to be ruptured when the battery cell is decompressed to discharge a pressure inside the battery cell.

2. The enclosure of claim 1, wherein at least one end of the weakened portion extends to an edge of the wall portion.

3. A casing according to claim 2, wherein both ends of the weakened portion extend to both edges of the wall portion, respectively.

4. A casing according to claim 3, wherein the weakened portion extends at each end to opposite edges of the wall portion.

5. A casing according to claim 1, wherein the wall portions have first and second edges opposed in a first direction, at least one of the wall portions being provided with a plurality of the weakened portions, the plurality of weakened portions being provided at intervals in the first direction.

6. The housing of claim 5, wherein, in the first direction, the two weakened portions at both ends extend to the first edge and the second edge, respectively.

7. A casing according to claim 1, wherein the weakened portion is a closed structure extending along a closed path.

8. The enclosure of claim 1, wherein the weakened portion is a non-enclosed structure extending along a non-enclosed path.

9. The enclosure of claim 1, wherein the plurality of wall portions includes a bottom wall and a plurality of side walls, the plurality of side walls being disposed around the bottom wall, at least two of the side walls being formed with the weakened portions.

10. A casing according to claim 9, wherein each of the side walls is provided with the weakened portion.

11. A casing according to claim 9 or 10, wherein the side wall has first and second opposed edges, the first edge being located where the side wall joins the base wall, the two ends of the weakened portion extending to the first and second edges respectively.

12. A casing according to claim 11, wherein the direction of extension of the weakened portion is perpendicular to the direction of extension of the first edge.

13. The housing of claim 11, wherein the weak portion is provided at a central position of the side wall in an extending direction of the first edge.

14. The enclosure of claim 9 or 10, wherein the bottom wall and the plurality of side walls are integrally formed.

15. The housing of claim 1, wherein the weakened portion is formed by providing a score groove in the wall portion.

16. The enclosure of claim 15, wherein the score groove is a linear groove.

17. The enclosure of claim 1, wherein the weakened portion is formed by annealing the wall portion.

18. A battery cell, comprising:

the housing of any one of claims 1-17;

an electrode assembly housed within the case.

19. A battery, comprising:

a box body;

the battery cell of claim 18, contained within the case.

20. An electrical consumer, comprising a battery according to claim 19, the battery being configured to provide electrical energy to the electrical consumer.

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