CN215989101U - Pressure relief device, single battery, battery and electric equipment - Google Patents

Abstract

The embodiment of the application provides a pressure relief device, a single battery, a battery and electric equipment, and belongs to the technical field of batteries. Pressure relief device includes pressure release body and pressure relief structure, and pressure relief structure is including setting up in the first mark groove of carving of pressure release body, second mark groove and third mark groove of carving, and first mark groove of carving is carved with the third mark groove interval and is set up, and first mark groove of carving is carved with the mark groove with the third and is all intersected with the second mark groove of carving, and first mark groove of carving, second mark groove of carving defines the pressure release portion jointly with the third mark groove of carving. The pressure relief portion is configured to open with the first, second, and third indenting grooves as boundaries when a pressure or temperature inside the battery cell reaches a threshold value to relieve the pressure inside. Pressure relief device is at the pressure release in-process, and pressure relief portion is carved with mark groove, second and is carved mark groove and third and carve mark groove and open, has improved pressure relief device's pressure release area, and then has improved pressure relief device's pressure release rate, has reduced the risk that battery monomer catches fire, explode, has improved the free security of battery.

Description

Pressure relief device, single battery, battery and electric equipment

Technical Field

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

Background

Batteries are widely used in electronic devices such as mobile phones, notebook computers, battery cars, electric automobiles, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, electric tools, and the like.

In addition to improving the performance of the battery cell, safety issues are also a concern in the development of battery technology.

Therefore, how to improve the safety of the battery cell is a problem to be solved urgently in the battery technology.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a pressure relief device, a single battery, a battery and electric equipment, and can effectively improve the safety of the single battery.

In a first aspect, an embodiment of the present application provides a pressure relief device, for a battery cell, including: a pressure relief body; the pressure relief structure comprises a first mark engraving groove, a second mark engraving groove and a third mark engraving groove which are arranged on the pressure relief body, the first mark engraving groove and the third mark engraving groove are arranged at intervals, the first mark engraving groove and the third mark engraving groove are intersected with the second mark engraving groove, and the first mark engraving groove, the second mark engraving groove and the third mark engraving groove define a pressure relief portion together; wherein the pressure relief portion is configured to open with the first, second, and third indenting grooves as boundaries when the pressure or temperature inside the battery cell reaches a threshold value, so as to relieve the pressure inside the battery cell.

Among the above-mentioned technical scheme, first mark carving groove and third mark carving groove interval among the pressure relief structure set up, first mark carving groove and third mark carving groove all intersect with the second mark carving groove, first mark carving groove, second mark carving groove and third mark carving groove three inject pressure relief portion jointly, when battery monomer thermal runaway makes battery monomer internal pressure or temperature reach the threshold value, pressure relief portion will use first mark carving groove, second mark carving groove and third mark carving groove to open as the boundary, in order to reach the purpose of the pressure of the single internal portion of battery of releasing. Pressure relief device is at the pressure release in-process, and pressure relief portion opens with first mark groove, second mark groove and third mark groove of carving, and pressure relief portion's the area of opening is great, has improved pressure relief device's pressure release area, and then has improved pressure relief device's pressure release rate, has reduced the battery monomer and has leaded to the risk of catching fire, explosion because of thermal runaway, has improved the free security of battery.

In some embodiments, the first scoring groove, the second scoring groove, and the third scoring groove collectively define two of the vent portions, the two vent portions being demarcated by the second scoring groove.

Among the above-mentioned technical scheme, first mark groove, second mark groove and third mark groove of carving inject two pressure relief portions with second mark groove boundary jointly, and at the pressure release in-process, two pressure relief portions can be opened fast with the mode of bisecting, when guaranteeing to have sufficient pressure release area, have improved the efficiency of opening of pressure relief portion, realize quick pressure release.

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

Among the above-mentioned technical scheme, two pressure relief portion symmetric distribution are in the both sides of second indent groove for two pressure relief portion's size, shape are the same, are favorable to two pressure relief portion to open simultaneously, and difficult appearance one pressure relief portion opens earlier, and another pressure relief portion opens afterwards, the condition of not opening even.

In some embodiments, the second indentation groove has a first weak point, a second weak point, and a third weak point, the second indentation groove intersects with the first indentation groove at the first weak point, the second indentation groove intersects with the third indentation groove at the third weak point, and the second weak point is located between the first weak point and the third weak point in the extending direction of the second indentation groove; the pressure relief body is configured to rupture from the second weakened position to the first weakened position and the third weakened position at the second score groove and form a first fracture when the internal pressure or temperature of the battery cell reaches a threshold value, such that the pressure relief portion opens along the first score groove and the third score groove after the pressure relief body forms the first fracture.

Among the above-mentioned technical scheme, the weak position of second is located between weak position of first weak position and the third, the weak position of second is the pressure release initial position, when battery monomer internal pressure or temperature reach the threshold value, the pressure release body will be cracked along the second nick groove from the weak position of second to the weak position of first weak position and the third of both sides, afterwards, the pressure release body will be cracked along first nick groove and third nick groove, thereby make the pressure release body open along first nick groove and third nick groove after the second nick groove is cracked, realize the quick opening of pressure release portion, improve pressure release efficiency.

In some embodiments, the pressure relief structure further includes a fourth score groove disposed on the pressure relief body, and the fourth score groove and the second score groove intersect at the second weak point.

Among the above-mentioned technical scheme, fourth trace groove and second trace groove intersect in the weak position of second, that is to say, the crossing position of fourth trace groove and second trace groove forms the weak position of second, forms the weak position of second through the mode that sets up fourth trace groove on the pressure release body, simple structure, low in manufacturing cost. In addition, at the initial stage of pressure release, the pressure release body can split along second nick groove and fourth nick groove, forms local pressure release before the pressure release portion is not opened completely.

In some embodiments, the depth of the first score groove, the depth of the second score groove, and the depth of the third score groove are all less than the depth of the fourth score groove.

Among the above-mentioned technical scheme, the degree of depth of first trace groove, the degree of depth of second trace groove and the degree of depth of third trace groove all are less than the degree of depth of fourth trace groove, that is to say, at first trace groove, the second trace groove, in third trace groove and the fourth trace groove, the degree of depth of fourth trace groove is deepest, make the fourth trace groove more weak with the second weak position that second trace groove intersected formation, the pressure release body is in the second weak position than first weak position and the more easily fracture of third weak position, thereby guarantee at the pressure release in-process, the pressure release body splits apart to the first weak position and the third weak position of both sides from the second weak position along the second trace groove.

In some embodiments, the depth of the first indent and the depth of the third indent are both equal to the depth of the second indent.

In the technical scheme, the depth of the first notching groove, the depth of the second notching groove and the depth of the third notching groove are equal, so that the first, second and third notching grooves can be conveniently machined and formed. In addition, because the degree of depth of first indent groove equals with the degree of depth of third indent groove, can guarantee the pressure release body along the uniformity that first indent groove and third indent groove split, be favorable to opening the pressure release portion fast.

In some embodiments, the depth of the first indent and the depth of the third indent are both less than the depth of a second indent equal to the depth of the fourth indent.

Among the above-mentioned technical scheme, the degree of depth that the fourth was carved the trace groove equals the degree of depth of second and is greater than the degree of depth of first mark groove and third mark groove of carving, this kind of structure makes the fourth be carved the trace groove and is more weak with the second weak position that the second score groove intersected formation, the pressure release body is in the second weak position and is more cracked more easily in first weak position and third weak position, thereby guarantee at the pressure release in-process, the pressure release body is along the second mark groove from the second weak position to the first weak position and the third weak position of both sides split.

In some embodiments, the depth of the first indent is equal to the depth of the third indent.

Among the above-mentioned technical scheme, the degree of depth of first indent groove equals with the degree of depth of third indent groove, can guarantee the uniformity that the pressure release body splits open along first indent groove and third indent groove, is favorable to opening the pressure release portion fast.

In some embodiments, the first scoring groove has a first end, the third scoring groove has a second end, and the fourth scoring groove has a third end, the first end, the second end, and the third end being located on the same side of the second scoring groove in a width direction of the second scoring groove; the length of the first notching groove from the first end to the first weak position is a first length, the length of the third notching groove from the second end to the third weak position is a second length, the length of the fourth notching groove from the third end to the second weak position is a third length, and the third length is smaller than the first length and the second length.

Among the above-mentioned technical scheme, third length is less than first length and second length for even pressure release body splits along fourth nick groove and can not form longer crack, the difficult pressure release body that appears splits the overlength along fourth nick groove and the condition that the pressure release body does not split at first nick groove or third nick groove position appears is favorable to the pressure relief portion to open along first nick groove and third nick groove.

In some embodiments, the first length is equal to the second length.

In the above technical scheme, the first length is equal to the second length, that is, the lengths of the first scoring groove and the third scoring groove on the same side of the second scoring groove are equal, so that the pressure relief portion can be opened more regularly.

In some embodiments, the first weak point is located at a midpoint of the first score groove, the second weak point is located at a midpoint of the fourth score groove, and the third weak point is located at a midpoint of the third score groove; the length of the fourth scoring groove is smaller than the length of the first scoring groove and the length of the third scoring groove.

Among the above-mentioned technical scheme, the weak position of first weak position, second weak position and third weak position is the mid point position of first mark carving groove, fourth mark carving groove and third mark carving groove respectively for the pressure release body forms two pressure release portions in the both sides of second mark carving groove, and at the pressure release in-process, two pressure release portions can be opened with the mode of foling fast, and the range of opening of two pressure release portions is unanimous basically. In addition, the length of the fourth scoring groove is smaller than that of the first scoring groove and that of the third scoring groove, and the pressure relief portion can be opened along the first scoring groove and the third scoring groove conveniently.

In some embodiments, the length of the first score groove is equal to the length of the third score groove.

Among the above-mentioned technical scheme, the length of first indent groove equals the length of third indent groove, and at the in-process of opening the pressure release portion, be favorable to the pressure release body to split apart completely in first indent groove and third indent groove department.

In some embodiments, the fourth score groove intersects and is arranged perpendicular to the second score groove.

Among the above-mentioned technical scheme, fourth nick groove and second nick groove are alternately and perpendicular arrangement for the crossing position stress of fourth nick groove and second nick groove is more concentrated, makes the pressure release body more easily break at the second weak point.

In some embodiments, the wall thickness of the pressure relief body at the first point of weakness and the wall thickness of the pressure relief body at the third point of weakness are both greater than the wall thickness of the pressure relief body at the second point of weakness.

Among the above-mentioned technical scheme, the pressure release body is greater than the wall thickness of the weak position of second at the wall thickness of the weak position of first weak position and third, that is to say, the pressure release body is thinner at the wall thickness of the weak position of second for the pressure release body is compared in first weak position and the weak position of third and is more cracked easily at the second weak point, thereby guarantee at the pressure release in-process, the pressure release body is carved the mark groove along the second and is split to the first weak position and the weak position of third of both sides from the weak position of second.

In some embodiments, the second score groove has opposite fourth and fifth ends in a direction of extension of the second score groove, the first score groove being closer to the fourth end than the third score groove, the third score groove being closer to the fifth end than the first score groove; the fourth end exceeds the first scoring groove along the direction of the first scoring groove back to the third scoring groove; and/or the fifth end exceeds the third scored groove along the direction of the third scored groove departing from the first scored groove.

Among the above-mentioned technical scheme, the fourth end of second nick groove surpasss first nick groove along the direction that first nick groove deviates from the third nick groove, is favorable to forming first weak position at the crossing position of first nick groove and second nick groove, and the pressure release body splits along first nick groove with first weak position as the starting point more easily after splitting along the second nick groove. The fifth end of the second score line groove exceeds the third score line groove along the direction that the third score line groove deviates from the first score line groove, and the third weak position is formed at the intersection position of the third score line groove and the second score line groove, and the pressure relief body is cracked along the third score line groove by taking the third weak position as the starting point after being cracked along the second score line groove.

In some embodiments, the pressure relief body is provided with a recess, and the pressure relief structure is arranged on the bottom surface of the recess.

Among the above-mentioned technical scheme, pressure relief structure sets up in the bottom surface of concave part, and the degree of depth of each mark groove among the pressure relief structure need not to process too deeply, reduces the shaping degree of difficulty of each mark groove.

In some embodiments, a receiving cavity for receiving an electrode assembly is formed inside the pressure relief body, the pressure relief body has a plurality of walls defining the receiving cavity, and at least one wall is provided with the pressure relief structure.

Among the above-mentioned technical scheme, pressure release body inside is formed with the chamber that holds that is used for holding electrode subassembly, and a plurality of walls of pressure release body are injectd and are held the chamber, and pressure relief device is for the shell structure that can hold electrode subassembly promptly, and the pressure relief device collection holds function and pressure release function as an organic whole.

In some embodiments, the pressure relief structure is disposed on an outer surface of the wall.

Among the above-mentioned technical scheme, pressure relief structure sets up in the surface of wall, the processing of each mark carving groove in the pressure relief structure of being convenient for.

In some embodiments, the wall is provided with a recess recessed from an outer surface to an inner surface of the wall, and the pressure relief structure is provided on a bottom surface of the recess.

Among the above-mentioned technical scheme, pressure relief structure sets up in the bottom surface of concave part, and the degree of depth of each mark groove among the pressure relief structure need not to process too deeply, reduces the shaping degree of difficulty of each mark groove. In addition, because the concave part is inwards sunken from the outer surface of the wall, the concave part can provide an avoiding space for the pressure relief part, so that the pressure relief part is at least partially accommodated in the concave part after being opened, and the space occupied by the pressure relief part except the outer surface of the wall after being opened is reduced.

In a second aspect, embodiments of the present application provide a battery cell, including the pressure relief device 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: any one of the embodiments of the second aspect provides a battery cell; and a case for accommodating the battery cell.

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

In a fifth aspect, an embodiment of the present application provides a manufacturing apparatus for a pressure relief device, including: 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 mark engraving groove, a second mark engraving groove and a third mark engraving groove which are arranged on the pressure relief body, the first mark engraving groove and the third mark engraving groove are arranged at intervals, the first mark engraving groove and the third mark engraving groove are intersected with the second mark engraving groove, the first mark engraving groove, the second mark engraving groove and the third mark engraving groove jointly define a pressure relief portion, and the pressure relief portion is configured to be opened by taking the first mark engraving groove, the second mark engraving groove and the third mark engraving groove as boundaries when the internal pressure or temperature of the battery monomer reaches a threshold value so as to relieve the internal pressure of the battery monomer.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used 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 for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

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

fig. 2 is a schematic structural diagram of a battery provided in 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 illustration of a pressure relief device according to some embodiments of the present disclosure;

FIG. 5 is a partial view of the pressure relief device shown in FIG. 4;

FIG. 6 is a schematic diagram of a pressure relief device according to yet other embodiments of the present disclosure;

FIG. 7 is a partial view of the pressure relief device shown in FIG. 6;

FIG. 8 is a schematic illustration of a pressure relief device according to yet another embodiment of the present disclosure;

FIG. 9 is a flow chart of a method of manufacturing a pressure relief device provided in some embodiments of the present application;

fig. 10 is a schematic block diagram of an apparatus for manufacturing a pressure relief device 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; 22-an electrode assembly; 221-positive pole tab; 222-a negative electrode tab; 23-end caps; 231 — positive electrode terminal; 232-negative electrode terminal; 24-an insulator; 25-a pressure relief device; 251-a pressure relief body; 2511-a recess; 252-a pressure relief structure; 2521-first scoring groove; 2521 a-first end; 2522-a second score groove; 2522 a-fourth end; 2522 b-fifth end; 2523-third scoring groove; 2523 a-a second end; 2524-a pressure relief portion; 2525-first weak bit; 2526-second weak bit; 2527-the third weak bit; 2528-fourth score groove; 2528 a-a third terminal; 26-a current collecting member; 100-a battery; 200-a controller; 300-a motor; 1000-a vehicle; 2000-manufacturing equipment; 2100-providing means; 2200-processing means.

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 above figures 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 pole piece, a negative pole piece and an isolating membrane. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece includes anodal mass flow body and anodal active substance layer, and anodal active substance layer coats in anodal mass flow body's surface, and the anodal mass flow body protrusion in the anodal mass flow body that has coated anodal active substance layer of uncoated anodal active substance layer, and the anodal mass flow body that does not coat anodal active substance layer is as anodal utmost point ear. 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 negative pole active substance layer coats in the surface of negative pole mass flow body, and the negative pole mass flow body protrusion in the negative pole mass flow body of coating the negative pole active substance layer not coating the negative pole active substance layer, and the negative pole mass flow body of not coating the negative pole active substance layer is as negative pole utmost point 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, the number of the positive electrode tabs is multiple and the positive electrode tabs are stacked together, and the number of the negative electrode tabs is multiple and the negative electrode tabs are stacked together. 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.

The development of battery technology needs to consider various design factors, such as energy density, cycle life, discharge capacity, charge and discharge rate, and other performance parameters, and also needs to consider the safety of the battery.

In the single battery, in order to ensure the safety of the single battery, a pressure relief device is generally arranged in the single battery, and the pressure inside the single battery is relieved through the pressure relief device so as to ensure the safety of the single battery.

The inventor found that even if a pressure relief device is provided in a battery cell, the risk of ignition and explosion of the battery cell still occurs. The inventor further researches and discovers that the conventional pressure relief device is generally provided with a scored groove on a pressure relief body, and the pressure relief body cracks from the position of the scored groove during pressure relief so as to discharge the emissions from the scored groove to achieve the purpose of pressure relief. The pressure relief device generally adopts a line-shaped mark carving groove, the pressure relief area is small, the pressure relief efficiency is low, the discharge inside the battery monomer cannot be discharged in time when the battery monomer is out of control due to heat, the conditions of fire and explosion occur, and the safety problem exists.

In view of this, the embodiment of the present application provides a pressure relief device, a first notching groove, a second notching groove, and a third notching groove are disposed on a pressure relief body, the first notching groove and the third notching groove are disposed at an interval, the first notching groove and the third notching groove are both intersected with the second notching groove, the first notching groove, the second notching groove, and the third notching groove define a pressure relief portion together, and the pressure relief portion is configured to be opened with the first notching groove, the second notching groove, and the third notching groove as a boundary when the pressure or the temperature inside a battery monomer reaches a threshold value, so as to relieve the pressure inside the battery monomer.

In such pressure relief device, pressure relief portion opens with first mark groove, second mark groove and third mark groove of carving, and pressure relief portion's opening area is great, has improved pressure relief device's pressure release area, and then has improved pressure relief device's pressure release rate, has reduced the single risk that leads to catching fire, explosion because of thermal runaway of battery, has improved the single security of battery.

The pressure relief device described in the embodiments of the present application is suitable for a battery cell, a battery, and an electric device 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 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 and the like; spacecraft include aircraft, rockets, space shuttles, and spacecraft, among others; 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 explanation, the following embodiments will be described by taking an electric device 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 disclosure, a battery 100 is disposed inside the vehicle 1000, and the battery 100 may be disposed at a bottom portion, a head portion, or a tail portion of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000.

The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

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

Referring to fig. 2, fig. 2 is a schematic structural diagram of a battery 100 according to some embodiments of the present disclosure, 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 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, and the first portion 11 and the second portion 12 cover each other to define a receiving space for receiving the battery cell 20. The first and second portions 11 and 12 may be in various shapes, such as rectangular parallelepiped, cylindrical, etc. The first portion 11 may be a hollow structure with one side open, the second portion 12 may also be a hollow structure with one side open, and the open side of the second portion 12 is covered on the open side of the first portion 11, thereby forming the box body 10 with a receiving space. The first portion 11 may have a hollow structure with one side opened, the second portion 12 may have a plate-like structure, and the second portion 12 may cover the opened side of the first portion 11 to form the case 10 having an accommodating space. The first part 11 and the second part 12 may be sealed by a sealing element, which may be a sealing ring, a sealant or the like.

In the battery 100, one or more battery cells 20 may be provided. If there are a plurality of battery cells 20, the plurality of battery cells 20 may be connected in series, in parallel, or in series-parallel, where in series-parallel refers to that the plurality of battery cells 20 are connected in series or in parallel. A plurality of battery cells 20 may be connected in series, in parallel, or in series-parallel to form a battery module, and a plurality of battery modules may be connected in series, in parallel, or in series-parallel to form a whole, and may be accommodated in the case 10. Or all the battery cells 20 may be directly connected in series or in parallel or in series-parallel, and the whole of all the battery cells 20 is accommodated in the case 10.

In some embodiments, the battery 100 may further include a bus member, and the plurality of battery cells 20 may be electrically connected to each other through the bus member, so as to connect the plurality of battery cells 20 in series or in parallel or in series-parallel. 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 disclosure, in which the battery cell 20 includes a case 21, an electrode assembly 22, an end cap 23, an insulating member 24, and a pressure relief device 25.

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 with an opening. The housing 21 may be in 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.

One or more electrode assemblies 22 may be provided in the case 21. For example, as shown in fig. 3, the electrode assembly 22 is plural, and the plural electrode assemblies 22 are arranged in a stack.

The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. The electrode assembly 22 may include a positive electrode tab, a negative electrode tab, and a separator. The electrode assembly 22 may have a winding type structure formed by winding a positive electrode tab, a separator, and a negative electrode tab, or a lamination type structure formed by laminating a positive electrode tab, a separator, and a negative electrode tab.

The positive electrode sheet may include a positive electrode current collector and positive electrode active material layers coated on opposite sides of the positive electrode current collector. The negative electrode tab may include a negative electrode current collector and a negative electrode active material layer coated on opposite sides of the negative electrode current collector. The electrode assembly 22 has a positive electrode tab 221 and a negative electrode tab 222, and the positive electrode tab 221 may be a portion of the positive electrode sheet not coated with the positive electrode active material layer, and the negative electrode tab 222 may be a portion of the negative electrode sheet not coated with the negative electrode active material layer.

The end cap 23 is a member that covers an opening of the case 21 to isolate the internal environment of the battery cell 20 from the external environment. The end cap 23 covers an 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 cap 23 can be adapted to the shape of the housing 21, for example, the housing 21 has a rectangular parallelepiped structure, the end cap 23 has a rectangular plate structure adapted to the housing 21, and for example, the housing 21 has a cylindrical structure, and the end cap 23 has a circular plate structure adapted to the housing 21. The end cap 23 may be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc., and the material of the end cap 23 may be the same as or different from that of the housing 21.

The end cap 23 may be provided thereon with electrode terminals for electrical connection with the electrode assembly 22 to output electric power of the battery cell 20. The electrode terminals may include a positive electrode terminal 231 for electrical connection with the positive tab 221 and a negative electrode terminal 232 for electrical connection with the negative tab 222. 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 electrically connected to the positive tab 221 via one current collecting member 26, and the negative electrode terminal 232 is electrically connected to the negative tab 222 via another current collecting member 26.

The insulating member 24 is a member that separates the case 21 from the electrode assembly 22, and the insulating separation of the case 21 from the electrode assembly 22 is achieved by the insulating member 24. The insulator 24 is an insulating material, and the insulator 24 may be an insulating material such as plastic, rubber, or the like. Illustratively, the insulating member 24 circumferentially covers the outer periphery of the electrode assembly 22, and it is understood that in the case of a plurality of electrode assemblies 22, the insulating member 24 circumferentially covers the outer periphery of the entirety of the plurality of electrode assemblies 22.

The pressure relief device 25 is a component that relieves the pressure inside 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 by the pressure relief device 25. The specific structure of the pressure relief device 25 will be explained in detail below with reference to the drawings.

Referring to fig. 4, fig. 4 is a schematic structural view of a pressure relief device 25 according to some embodiments of the present disclosure, the pressure relief device 25 is used for a battery cell 20, and the pressure relief device 25 includes a pressure relief body 251 and a pressure relief structure 252. The pressure relief structure 252 includes a first score groove 2521, a second score groove 2522, and a third score groove 2523 disposed on the pressure relief body 251, the first score groove 2521 and the third score groove 2523 are disposed at an interval, the first score groove 2521 and the third score groove 2523 are both intersected with the second score groove 2522, and the first score groove 2521, the second score groove 2522, and the third score groove 2523 together define a pressure relief portion 2524. Wherein the pressure relief portion 2524 is configured to open at the boundaries of the first, second, and third score grooves 2521, 2522, and 2523 when the pressure or temperature inside the battery cell 20 reaches a threshold value, to relieve the pressure inside the battery cell 20.

The pressure relief body 251 may be a component mounted on the end cap 23, for example, the pressure relief body 251 is a plate-shaped structure mounted on the end cap 23, and specifically, the pressure relief body 251 may be an explosion-proof plate mounted on the end cap 23. The pressure relief body 251 may also be the case 21 for accommodating the electrode assembly 22. For example, in fig. 4, the housing 21 is the pressure relief body 251, and the respective score grooves (e.g., the first score groove 2521, the second score groove 2522, and the third score groove 2523) in the pressure relief structure 252 may be directly formed on the housing 21.

The first score groove 2521, the second score groove 2522 and the third score groove 2523 may be formed in various manners, such as punch forming, milling forming, and the like, and the embodiments of the present invention are not particularly limited thereto. The first, second, and third score grooves 2521, 2522, and 2523 may be linear grooves extending along a straight line, and the first, second, and third score grooves 2521, 2522, and 2523 may be non-linear grooves, such as arc-shaped grooves. If the first, second and third score grooves 2521, 2522 and 2523 are linear grooves extending along a straight line, the first and third score grooves 2521 and 2523 may be disposed in parallel or non-parallel; the first and second score grooves 2521 and 2522 may be disposed vertically or non-vertically; the third indent 2523 and the second indent 2522 may be vertically arranged or not vertically arranged. The first, second, and third score grooves 2521, 2522, and 2523 may each be a V-shaped groove having a V-shaped cross section.

The pressure relief portion 2524 is a region of the pressure relief body 251 defined by the first, second and third score grooves 2521, 2522 and 2523, and it can also be understood that three edges of the pressure relief portion 2524 are located at corresponding positions of the first, second and third score grooves 2521, 2522 and 2523, respectively. When the pressure or temperature inside the battery cell 20 reaches a threshold value, the pressure relief portion 2524 will be opened with the first, second, and third score grooves 2521, 2522, and 2523 as boundaries, that is, the pressure relief body 251 will be cracked at the positions of the first, second, and third score grooves 2521, 2522, and 2523 to achieve the opening of the pressure relief portion 2524, and the pressure relief body 251 may be completely cracked or partially cracked at the positions of the second and third score grooves 2522 and 2523. After the pressure relief portion 2524 is opened, the pressure relief body 251 forms an opening at a position corresponding to the pressure relief portion 2524, and the exhaust (gas, electrolyte, etc.) inside the battery cell 20 can be discharged through the opening, so as to achieve the purpose of relieving the pressure inside the battery cell 20. The pressure relief portion 2524 in the opening process, the pressure relief portion 2524 may be turned open in the flow direction of the effluent inside the battery cell 20.

It should be noted that one or two relief portions 2524 defined by the first, second and third score grooves 2521, 2522 and 2523 may be provided. For example, the second score groove 2522 is disposed at one end of the first score groove 2521 and the third score groove 2523, the first score groove 2521, the second score groove 2522 and the third score groove 2523 form an approximate "Contraband" structure, and the first score groove 2521, the second score groove 2522 and the third score groove 2523 define a relief portion 2524; for another example, the second score groove 2522 is disposed at the middle position of the first score groove 2521 and the third score groove 2523, the first score groove 2521, the second score groove 2522 and the third score groove 2523 form an approximate "H" shape structure, and the first score groove 2521, the second score groove 2522 and the third score groove 2523 define two pressure relief portions 2524.

In the pressure relief device 25, since the first score groove 2521 and the third score groove 2523 in the pressure relief structure 252 are arranged at an interval, the first score groove 2521 and the third score groove 2523 are intersected with the second score groove 2522, and the first score groove 2521, the second score groove 2522 and the third score groove 2523 together define a pressure relief portion 2524, when the battery cell 20 is thermally runaway and the internal pressure or temperature of the battery cell 20 reaches a threshold value, the pressure relief portion 2524 is opened with the first score groove 2521, the second score groove 2522 and the third score groove 2523 as a boundary, so as to achieve the purpose of relieving the internal pressure of the battery cell 20. In the pressure relief process of the pressure relief device 25, the pressure relief portion 2524 is opened by the first notch groove 2521, the second notch groove 2522 and the third notch groove 2523, the opening area of the pressure relief portion 2524 is large, the pressure relief area of the pressure relief device 25 is increased, the pressure relief rate of the pressure relief device 25 is increased, the risk of fire and explosion caused by thermal runaway of the battery cell 20 is reduced, and the safety of the battery cell 20 is improved.

In some embodiments, referring to fig. 5, fig. 5 is a partial view of the pressure relief device 25 shown in fig. 4, the first score groove 2521, the second score groove 2522 and the third score groove 2523 together define two pressure relief portions 2524, and the two pressure relief portions 2524 are demarcated by the second score groove 2522.

The first, second and third score grooves 2521, 2522 and 2523 may form an approximate "H" shape. The size of the two pressure relief portions 2524 may or may not be equal.

Because the first score groove 2521, the second score groove 2522 and the third score groove 2523 jointly define two pressure relief portions 2524 demarcated by the second score groove 2522, in the pressure relief process, the two pressure relief portions 2524 can be opened rapidly in a split manner, so that the pressure relief area is ensured, the opening efficiency of the pressure relief portions 2524 is improved, and rapid pressure relief is realized.

In some embodiments, the two relief portions 2524 are symmetrically distributed on both sides of the second score groove 2522.

The second score groove 2522 can be considered as a symmetry axis of the two pressure relief portions 2524, and the two pressure relief portions 2524 are symmetrical with respect to the second score groove 2522.

Because the two pressure relief portions 2524 are symmetrically distributed on both sides of the second score groove 2522, the two pressure relief portions 2524 have the same size and shape, which is beneficial for opening the two pressure relief portions 2524 at the same time, and the situation that one pressure relief portion 2524 is opened first and the other pressure relief portion 2524 is opened later, or even not opened, does not occur easily.

In some embodiments, with continued reference to fig. 5, the second score groove 2522 has a first weak point 2525, a second weak point 2526 and a third weak point 2527, the second score groove 2522 intersects the first score groove 2521 at the first weak point 2525, the second score groove 2522 intersects the third score groove 2523 at the third weak point 2527, and the second weak point 2526 is located between the first weak point 2525 and the third weak point 2527 in the extending direction of the second score groove 2522; the pressure relief body 251 is configured to rupture and form a first fracture at the second score groove 2522 from the second weak point 2526 to the first and third weak points 2525 and 2527 when the pressure or temperature inside the battery cell 20 reaches a threshold value, such that the pressure relief portion 2524 opens along the first and third score grooves 2521 and 2523 after the first fracture is formed in the pressure relief body 251.

The first, second and third weak points 2525, 2526 and 2527 are the three weak points of the third score groove 2523, the first weak point 2525 being the point where the pressure relief body 251 is first ruptured at the first score groove 2521, the second weak point 2526 being the point where the pressure relief body 251 is first ruptured at the second score groove 2522, and the third weak point 2527 being the point where the pressure relief body 251 is first ruptured at the third score groove 2523. The pressure relief body 251 is configured to rupture at the second score groove 2522 from the second point of weakness 2526 towards the first and third points of weakness 2525, 2527 when a pressure or temperature inside the battery cell 20 reaches a threshold value, and forms a first fracture, it being understood that the second point of weakness 2526 is weaker than the first and third points of weakness 2525, 2527, i.e. the second point of weakness 2526 is more easily ruptured on the pressure relief body 251 than the first and third points of weakness 2525, 2527, during the pressure relief process the second point of weakness 2526 rupturing first, so that the pressure relief body 251 ruptures from the second point of weakness 2526 towards the first and third points of weakness 2525, 2527 and forms a first fracture.

The second score groove 2522 intersects the first score groove 2521 at the first weak point 2525, and the second score groove 2522 intersects the first score groove 2521 to form the first weak point 2525. The second score groove 2522 and the third score groove 2523 intersect at a third weak point 2527, the intersection of the second score groove 2522 and the third score groove 2523 is the third weak point 2527, and the intersection of the second score groove 2522 and the third score groove 2523 forms the third weak point 2527. In the molding process, after the first score groove 2521, the second score groove 2522 and the third score groove 2523 are processed on the pressure relief body 251, a first weak point 2525 is formed at a position where the first score groove 2521 and the second score groove 2522 intersect, and a third weak point 2527 is formed at a position where the third score groove 2523 and the second score groove 2522 intersect.

The second point of weakness 2526 may or may not be equidistant from the first point of weakness 2525 and the second point of weakness 2526 may or may not be equidistant from the third point of weakness 2527. The second weak point 2526 may be formed in various ways, for example, the second scored groove 2522 is a gradually changing groove with gradually changing depth, the depth of the second scored groove 2522 gradually decreases from the second weak point 2526 to both ends, and the second weak point 2526 is formed at the deepest position of the second scored groove 2522; for another example, another scored groove may be formed in the pressure relief body 251, and the scored groove may intersect with the second scored groove 2522 to form a second weak point 2526.

In this embodiment, the second weak point 2526 is located between the first weak point 2525 and the third weak point 2527, the second weak point 2526 is a pressure relief starting point, when the internal pressure or temperature of the battery cell 20 reaches a threshold value, the pressure relief body 251 will be ruptured along the second score groove 2522 from the second weak point 2526 to the first weak point 2525 and the third weak point 2527 on both sides, and then the pressure relief body 251 will be ruptured along the first score groove 2521 and the third score groove 2523, so that the pressure relief portion 2524 is opened along the first score groove 2521 and the third score groove 2523 after the pressure relief body 251 is ruptured along the second score groove 2522, thereby achieving quick opening of the pressure relief portion 2524 and improving pressure relief efficiency.

In some embodiments, referring to fig. 6 and 7, fig. 6 is a schematic structural view of a pressure relief device 25 according to still other embodiments of the present disclosure, fig. 7 is a partial view of the pressure relief device 25 shown in fig. 6, the pressure relief structure 252 further includes a fourth score groove 2528 disposed on the pressure relief body 251, and the fourth score groove 2528 and the second score groove 2522 intersect at a second weak point 2526.

The fourth score groove 2528 intersects the second score groove 2522, and one end of the fourth score groove 2528 is connected to the second score groove 2522, for example, the fourth score groove 2528 and the second score groove 2522 form an approximately "T" shaped structure, or the fourth score groove 2528 and the second score groove 2522 are arranged in an intersecting manner, for example, the fourth score groove 2528 and the second score groove 2522 form an approximately "ten" shaped structure.

The fourth score groove 2528 intersects the second score groove 2522 at the second weak point 2526, and the fourth score groove 2528 intersects the second score groove 2522 to form the second weak point 2526. After the fourth scored groove 2528 and the second scored groove 2522 are formed in the pressure relief body 251 during the molding process, a second weak point 2526 is formed at a position where the fourth scored groove 2528 and the second scored groove 2522 intersect.

The fourth score groove 2528 may be a linear groove extending in a straight line. The fourth score groove 2528 is located between the first score groove 2521 and the third score groove 2523. The fourth score groove 2528 and the first score groove 2521 may be disposed in parallel or not, and the fourth score groove 2528 and the third score groove 2523 may be disposed in parallel or not.

The fourth score groove 2528 can be formed in a variety of ways, such as punch forming, milling, etc. The fourth score groove 2528 may be a V-shaped groove having a V-shaped cross section.

In this embodiment, the second weak point 2526 is formed by providing the fourth scored groove 2528 on the pressure relief body 251, which has a simple structure and low manufacturing cost. In addition, at the initial stage of pressure relief, the pressure relief body 251 may be split along the second and fourth scored grooves 2522 and 2528, forming a partial pressure relief before the pressure relief portion 2524 is completely opened.

In some embodiments, the depth of the first score groove 2521, the depth of the second score groove 2522, and the depth of the third score groove 2523 are all less than the depth of the fourth score groove 2528.

Among the first, second, third and fourth score grooves 2521, 2522, 2523 and 2528, the fourth score groove 2528 has the deepest depth, and the wall thickness of the pressure relief body 251 at the location of the fourth score groove 2528 is the smallest, so that the pressure relief body 251 is more easily ruptured at the second weak location 2526 where the fourth score groove 2528 meets the second score groove 2522.

Since the depth of the first score groove 2521, the depth of the second score groove 2522 and the depth of the third score groove 2523 are all less than the depth of the fourth score groove 2528, so that the second weak point 2526 formed by the intersection of the fourth score groove 2528 and the second score groove 2522 is weaker, the pressure relief body 251 is easier to rupture at the second weak point 2526 than at the first weak point 2525 and the third weak point 2527, thereby ensuring that the pressure relief body 251 is ruptured along the second score groove 2522 from the second weak point 2526 to the first weak point 2525 and the third weak point 2527 on both sides.

Illustratively, the depth of the first score groove 2521 and the depth of the third score groove 2523 are both equal to the depth of the second score groove 2522.

Since the depth of the first score groove 2521, the depth of the second score groove 2522, and the depth of the third score groove 2523 are equal, the first score groove 2521, the second score groove 2522, and the third score groove 2523 are conveniently formed. In addition, since the depth of the first score groove 2521 is equal to the depth of the third score groove 2523, the wall thickness of the pressure relief body 251 at the position of the first score groove 2521 is substantially the same as the wall thickness at the position of the third score groove 2523, so that the rupture consistency of the pressure relief body 251 along the first score groove 2521 and the third score groove 2523 can be ensured, and the quick opening of the pressure relief portion 2524 is facilitated.

In other embodiments, the depth of the first score groove 2521 and the depth of the third score groove 2523 are both less than the depth of the second score groove 2522, the depth of the second score groove 2522 being equal to the depth of the fourth score groove 2528.

The depth of the third score groove 2523 is equal to the depth of the fourth score groove 2528, and the depth of the first score groove 2521 and the depth of the third score groove 2523 are both less than the depth of the second score groove 2522, it being understood that the depth of the first score groove 2521 and the depth of the third score groove 2523 are also less than the depth of the fourth score groove 2528.

The depth of the fourth score groove 2528 is equal to the depth of the second score groove 2522 and greater than the depths of the first score groove 2521 and the third score groove 2523, such that the second weak point 2526 formed by the intersection of the fourth score groove 2528 and the second score groove 2522 is weaker than the first weak point 2525 and the third weak point 2527, and the pressure relief body 251 is more easily ruptured at the second weak point 2526 than at the first weak point 2525 and the third weak point 2527, thereby ensuring that the pressure relief body 251 is ruptured along the second score groove 2522 from the second weak point 2526 to the first weak point 2525 and the third weak point 2527 on both sides thereof during the pressure relief process.

Illustratively, the depth of the first score groove 2521 is equal to the depth of the third score groove 2523. Facilitating the processing and forming of the first and third score grooves 2521 and 2523. The consistency of the rupture of the pressure relief body 251 along the first and third scored grooves 2521 and 2523 can be ensured, which is beneficial for quickly opening the pressure relief portion 2524.

In some embodiments, referring to fig. 7, the first groove 2521 has a first end 2521a, the third groove 2523 has a second end 2523a, and the fourth groove 2528 has a third end 2528a, wherein the first end 2521a, the second end 2523a and the third end 2528a are located on the same side of the second groove 2522 in the width direction of the second groove 2522. The first score groove 2521 has a first length from the first end 2521a to the first weak point 2525, the third score groove 2523 has a second length from the second end 2523a to the third weak point 2527, and the fourth score groove 2528 has a third length from the third end 2528a to the second weak point 2526, the third length being less than the first and second lengths.

The first end 2521a is an end of the first score groove 2521 in the extending direction thereof, the second end 2523a is an end of the third score groove 2523 in the extending direction thereof, and the third end 2528a is an end of the fourth score groove 2528 in the extending direction thereof.

In the embodiment where the first, second and third score grooves 2521, 2522 and 2523 together define a pressure relief portion 2524, for example, the first, second and third score grooves 2521, 2522 and 2523 form an approximate "Contraband" structure, the end of the first score groove 2521 away from the second score groove 2522 is a first end 2521a, and the end of the third score groove 2523 away from the second score groove 2522 is a second end 2523 a. As shown in fig. 7, in the embodiment where the first, second and third score grooves 2521, 2522 and 2523 together define two pressure relief portions 2524, for example, the first, second and third score grooves 2521, 2522 and 2523 form an approximate "H" shape, both ends of the first score groove 2521 in the extending direction thereof may be first ends 2521a, and both ends of the third score groove 2523 in the extending direction thereof may be second ends 2523 a.

In this embodiment, since the third length is smaller than the first length and the second length, even if the pressure relief body 251 cracks along the fourth score groove 2528, a long crack is not formed, and the situation that the pressure relief body 251 cracks along the fourth score groove 2528 too long and the pressure relief body 251 does not crack at the first score groove 2521 or the third score groove 2523 is not easy to occur, which is beneficial for the pressure relief portion 2524 to open along the first score groove 2521 and the third score groove 2523.

Illustratively, the first length is equal to the second length. That is, the first and third score grooves 2521 and 2523 have the same length on the same side of the second score groove 2522, and the relief portion 2524 has the same length to be ruptured at the first and third score grooves 2521 and 2523.

In some embodiments, with continued reference to fig. 7, the first weak point 2525 is located at a midpoint of the first score groove 2521, the second weak point 2526 is located at a midpoint of the fourth score groove 2528, and the third weak point 2527 is located at a midpoint of the third score groove 2523. The length of the fourth score groove 2528 is less than the length of the first score groove 2521 and the length of the third score groove 2523.

The first weak point 2525 is located at the midpoint of the first score groove 2521, i.e., the second score groove 2522 divides the first score groove 2521 into two equal length portions. The second point of weakness 2526 is located at the midpoint of the fourth score groove 2528, i.e. the second score groove 2522 divides the fourth score groove 2528 into two equal length sections. The third weak point 2527 is located at the midpoint of the third score groove 2523, i.e. the second score groove 2522 divides the third score groove 2523 into two parts of equal length.

Since the first weak point 2525, the second weak point 2526 and the third weak point 2527 are respectively located at the midpoint of the first score groove 2521, the fourth score groove 2528 and the third score groove 2523, so that the pressure relief body 251 forms two pressure relief portions 2524 on both sides of the second score groove 2522, during the pressure relief process, the two pressure relief portions 2524 can be opened rapidly in a split manner, and the opening amplitude of the two pressure relief portions 2524 is substantially the same. Further, the length of the fourth score groove 2528 is less than the length of the first score groove 2521 and the length of the third score groove 2523, facilitating the opening of the pressure relief portion 2524 along the first and third score grooves 2521 and 2523. Further, the relatively short fourth score groove 2528 can reduce manufacturing costs.

In some embodiments, the length of the first score groove 2521 is equal to the length of the third score groove 2523. During the opening of the pressure relief portion 2524, it is advantageous for the pressure relief body 251 to be completely ruptured at the first and third scored grooves 2521 and 2523.

In some embodiments, the fourth score groove 2528 intersects the second score groove 2522 and is arranged vertically.

The fourth score groove 2528 and the second score groove 2522 intersect each other means that both ends of the fourth score groove 2528 extend to both sides of the second score groove 2522 in the width direction of the second score groove 2522, and both ends of the second score groove 2522 extend to both sides of the fourth score groove 2528 in the width direction of the fourth score groove 2528. For example, the fourth score groove 2528 and the second score groove 2522 form a "ten" shaped structure.

In this embodiment, both ends of the fourth score groove 2528 in the extending direction thereof may be third ends 2528 a.

In this embodiment, since the fourth score groove 2528 intersects and is vertically arranged with the second score groove 2522, stress is more concentrated at the intersection of the fourth score groove 2528 and the second score groove 2522, so that the pressure relief body 251 is more easily broken at the second weak point 2526.

In some embodiments, the wall thickness of the pressure relief body 251 at the first point of weakness 2525 and the wall thickness of the pressure relief body 251 at the third point of weakness 2527 are both greater than the wall thickness of the pressure relief body 251 at the second point of weakness 2526.

Taking the first scored groove 2521 and the second scored groove 2522 to form the first weak point 2525 as an example, the wall thickness of the pressure relief body 251 at the first weak point 2525 refers to the thickness of the portion of the pressure relief body 251 remaining at the first weak point 2525 after the first scored groove 2521 and the second scored groove 2522 are disposed; taking the example where the fourth scored groove 2528 intersects the second scored groove 2522 to form the second weakened location 2526, the wall thickness of the pressure relief body 251 at the second weakened location 2526 is the thickness of the portion of the pressure relief body 251 remaining at the second weakened location 2526 after the fourth scored groove 2528 and the second scored groove 2522 are provided; taking the example that the second scored groove 2522 intersects with the third scored groove 2523 to form the third weak point 2527, the wall thickness of the pressure relief body 251 at the third weak point 2527 refers to the thickness of the portion of the pressure relief body 251 remaining at the second weak point 2526 after the second scored groove 2522 and the third scored groove 2523 are provided.

The wall thickness of the pressure relief body 251 at the first weak point 2525 and the wall thickness of the pressure relief body 251 at the third weak point 2527 may each be greater than the wall thickness of the pressure relief body 251 at the second weak point 2526 by setting the depth of the first score groove 2521, the depth of the second score groove 2522 and the depth of the third score groove 2523 to be smaller than the depth of the fourth score groove 2528; the wall thickness of the pressure relief body 251 at the first weak point 2525 and the wall thickness of the pressure relief body 251 at the third weak point 2527 can be larger than the wall thickness of the pressure relief body 251 at the second weak point 2526 by the fact that the depth of the first score groove 2521 and the depth of the third score groove 2523 are both smaller than the depth of the second score groove 2522 and the depth of the second score groove 2522 is equal to the depth of the fourth score groove 2528; it is also possible to provide the first scored groove 2521 as a gradually changing groove with a gradually changing depth, such that the depth of the second scored groove 2522 gradually decreases from the location of the second point of weakness 2526 to both ends, so that both the wall thickness of the pressure relief body 251 at the first point of weakness 2525 and the wall thickness of the pressure relief body 251 at the third point of weakness 2527 are greater than the wall thickness of the pressure relief body 251 at the second point of weakness 2526.

In this embodiment, the wall thickness of the pressure relief body 251 at the first and third weak points 2525, 2527 is greater than the wall thickness of the second weak point 2526, i.e. the wall thickness of the pressure relief body 251 at the second weak point 2526 is thinner, so that the pressure relief body 251 is easier to break at the second weak point than at the first and third weak points 2525, 2527, thereby ensuring that the pressure relief body 251 is broken along the second score groove 2522 from the second weak point 2526 to the first and third weak points 2525, 2527 on both sides.

In some embodiments, in the extending direction of the second score groove 2522, the second score groove 2522 has a fourth end 2522a and a fifth end 2522b opposite to each other, the first score groove 2521 is closer to the fourth end 2522a than the third score groove 2523, and the third score groove 2523 is closer to the fifth end 2522b than the first score groove 2521. The fourth end 2522a exceeds the first score groove 2521 in a direction that the first score groove 2521 faces away from the third score groove 2523; and/or the fifth end 2522b exceeds the third score groove 2523 in a direction away from the first score groove 2521 along the third score groove 2523.

If the fourth end 2522a exceeds the first score groove 2521 in a direction away from the third score groove 2523 along the first score groove 2521 and the fifth end 2522b exceeds the third score groove 2523 in a direction away from the first score groove 2521 along the third score groove 2523, i.e. both ends of the second score groove 2522 exceed the first score groove 2521 and the third score groove 2523, respectively, it can be understood that the second score groove 2522 crosses the first score groove 2521 and the second score groove 2522 crosses the third score groove 2523.

The fourth end 2522a of the second score groove 2522 extends beyond the first score groove 2521 in the direction that the first score groove 2521 faces away from the third score groove 2523, so as to facilitate the formation of a first weak point 2525 at the intersection of the first score groove 2521 and the second score groove 2522, and the pressure relief body 251 is more easily ruptured along the first score groove 2521 starting from the first weak point 2525 after being ruptured along the second score groove 2522. The fifth end 2522b of the second score groove 2522 extends beyond the third score groove 2523 in a direction away from the first score groove 2521 along the third score groove 2523, which facilitates the formation of a third weak point 2527 at the intersection of the third score groove 2523 and the second score groove 2522, and the pressure relief body 251 is easier to rupture along the third score groove 2523 starting from the third weak point 2527 after rupturing along the second score groove 2522.

In some embodiments, please refer to fig. 8, fig. 8 is a schematic structural diagram of a pressure relief device 25 according to still other embodiments of the present disclosure, in which the pressure relief body 251 is provided with a recess 2511, and the pressure relief structure 252 is disposed on a bottom surface of the recess 2511.

The bottom surface of the recess 2511 is a surface where the recess 2511 is continuous with the side surface thereof. Taking the recess 2511 as a rectangle, the recess 2511 has four side surfaces, which surround the edge of the bottom surface.

The recess 2511 is a structure recessed from the surface of the pressure relief body 251 toward the inside of the pressure relief body 251. The pressure relief structure 252 is disposed on the bottom surface of the recess 2511, i.e., all of the scored grooves in the pressure relief structure 252 are disposed on the bottom surface of the recess 2511. In an embodiment where the pressure relief structure 252 includes a first score groove 2521, a second score groove 2522, and a third score groove 2523, the first score groove 2521, the second score groove 2522, and the third score groove 2523 are disposed on the bottom surface of the groove. In the embodiment where the pressure relief structure 252 includes the first, second, third and fourth score grooves 2521, 2522, 2523 and 2528, the first, second, third and fourth score grooves 2521, 2522, 2523 and 2528 are disposed on the bottom surface of the groove.

In the molding process, the recess 2511 may be formed on the pressure relief body 251, and then each of the score grooves may be formed on the bottom surface of the recess 2511.

The shape of the recess 2511 may be various, such as rectangular, circular, etc. In fig. 8, the recess 2511 is rectangular.

In this embodiment, since the pressure relief structure 252 is disposed on the bottom surface of the recess 2511, the depth of each score groove in the pressure relief structure 252 does not need to be processed too deeply, thereby reducing the molding difficulty of each score groove.

In some embodiments, with continued reference to fig. 8, a receiving cavity for receiving the electrode assembly 22 is formed inside the pressure relief body 251, the pressure relief body 251 has a plurality of walls defining the receiving cavity, and at least one wall is provided with a pressure relief structure 252.

At least one wall of the pressure relief body 251 is provided with a pressure relief structure 252, only one wall may be provided with the pressure relief structure 252, or a plurality of walls are provided with the pressure relief structures 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 may have various shapes, for example, a rectangular parallelepiped, a cylinder. Taking the pressure relief body 251 as a cuboid as an example, the pressure relief body 251 may have five walls, a bottom wall and four side walls jointly enclose and close to form an accommodating cavity with an opening at one end, and the bottom wall is provided with the pressure relief structure 252. Taking pressure relief body 251 as the cylinder for example, pressure relief body 251 can have two walls, a diapire and a circumference wall, and the edge of diapire is located in the closure to the circumference wall, and circumference wall and diapire enclose jointly and close the chamber that holds that forms one end open-ended, are provided with pressure relief structure 252 on the diapire.

In the present embodiment, since the pressure relief body 251 is internally formed with a receiving cavity for receiving the electrode assembly 22, a plurality of walls of the pressure relief body 251 define the receiving cavity, so that the pressure relief device 25 is the case 21 capable of receiving the electrode assembly 22, and the pressure relief device 25 integrates a receiving function and a pressure relief function.

In some embodiments, the pressure relief structure 252 is disposed on an outer surface of the wall to facilitate the machining of various score grooves in the pressure relief structure 252.

In some embodiments, with continued reference to fig. 8, in the case where the pressure relief body 251 is provided with a recess 2511, and the pressure relief structure 252 is disposed on the bottom surface of the recess 2511, the recess 2511 is disposed on the wall of the pressure relief body 251 and is recessed from the outer surface to the inner surface of the wall.

The inner surface of the wall is the surface of the wall facing electrode assembly 22 and the outer surface of the wall is the surface of the wall facing away from electrode assembly 22.

The pressure relief structure 252 is arranged on the bottom surface of the recess 2511, and the depth of each score line groove in the pressure relief structure 252 does not need to be processed too deeply, so that the molding difficulty of each score line groove is reduced. Furthermore, since the recess 2511 is recessed inwardly from the outer surface of the wall, the recess 2511 can provide a relief space for the pressure relief portion 2524, so that the pressure relief portion 2524 is at least partially accommodated within the recess 2511 after opening, reducing the space occupied by the pressure relief portion 2524 outside the outer surface of the wall after opening.

The embodiment of the present application provides a battery cell 20, which includes the pressure relief device 25 provided in any one of the above embodiments.

The embodiment of the application provides a battery 100, which comprises a box body 10 and a battery cell 20 provided by any one of the above embodiments, wherein the box body 10 is used for accommodating the battery cell 20.

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

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

Referring to fig. 6, an embodiment of the present disclosure further provides a housing for accommodating the electrode assembly 22, the housing is provided with a pressure relief structure 252, the pressure relief structure 252 includes a first score groove 2521, a second score groove 2522, a third score groove 2523 and a fourth score groove 2528 disposed on the housing, the first score groove 2521 and the third score groove 2523 are disposed at an interval, the fourth score groove 2528 is located between the first score groove 2521 and the third score groove 2523, the first score groove 2521, the third score groove 2523 and the fourth score groove 2528 all intersect with the second score groove 2522, and the first score groove 2521, the second score groove 2522 and the third score groove 2523 define a pressure relief portion 2524 together; wherein the pressure relief portion 2524 is configured to open at the boundaries of the first, second, and third score grooves 2521, 2522, and 2523 when the pressure or temperature inside the battery cell 20 reaches a threshold value, to relieve the pressure inside the battery cell 20. The shell of the structure has a large pressure relief area, so that the pressure relief rate is improved, the risks of fire and explosion caused by thermal runaway of the single battery 20 are reduced, and the safety of the single battery 20 is improved.

Referring to fig. 9, fig. 9 is a flowchart of a method for manufacturing a pressure relief device 25 according to some embodiments of the present disclosure, where the method includes:

s100: providing a pressure relief body 251;

s200: a pressure relief structure 252 is processed on the pressure relief body 251;

the pressure relief structure 252 includes a first score groove 2521, a second score groove 2522, and a third score groove 2523 disposed on the pressure relief body 251, the first score groove 2521 and the third score groove 2523 are disposed at an interval, the first score groove 2521 and the third score groove 2523 both intersect with the second score groove 2522, the first score groove 2521, the second score groove 2522, and the third score groove 2523 together define a pressure relief portion 2524, and the pressure relief portion 2524 is configured to open with the first score groove 2521, the second score groove 2522, and the third score groove 2523 as a boundary when the internal pressure or temperature of the battery cell 20 reaches a threshold value, so as to relieve the internal pressure of the battery cell 20.

In some embodiments, the pressure relief structure 252 further includes a fourth indent 2528 disposed on the pressure relief body 251, and the fourth indent 2528 is located between the first indent 2521 and the third indent 2523. The first score groove 2521, the second score groove 2522, the third score groove 2523 and the fourth score groove 2528 are formed in the pressure relief body 251 in a press forming manner.

It should be noted that, for the related structure of the pressure relief device 25 manufactured by the manufacturing method provided in the foregoing embodiments, reference may be made to the pressure relief device 25 provided in the foregoing embodiments, and details are not described herein again.

In addition, an apparatus 2000 for manufacturing a pressure relief device 25 is further provided in the embodiments of the present application, please refer to fig. 10, fig. 10 is a schematic block diagram of the apparatus 2000 for manufacturing the pressure relief device 25 according to some embodiments of the present application, the apparatus 2000 includes a providing device 2100 and a processing device 2200, the providing device 2100 is used for providing a pressure relief body 251, and the processing device 2200 is used for processing a pressure relief structure 252 on the pressure relief body 251.

The pressure relief structure 252 includes a first score groove 2521, a second score groove 2522, and a third score groove 2523 disposed on the pressure relief body 251, the first score groove 2521 and the third score groove 2523 are disposed at an interval, the first score groove 2521 and the third score groove 2523 both intersect with the second score groove 2522, the first score groove 2521, the second score groove 2522, and the third score groove 2523 together define a pressure relief portion 2524, and the pressure relief portion 2524 is configured to open with the first score groove 2521, the second score groove 2522, and the third score groove 2523 as a boundary when the internal pressure or temperature of the battery cell 20 reaches a threshold value, so as to relieve the internal pressure of the battery cell 20.

It should be noted that, with reference to the related structure of the pressure relief device 25 manufactured by the manufacturing apparatus 2000 provided in the foregoing embodiments, reference may be made to the pressure relief device 25 provided in each of the foregoing embodiments, and details are not described herein again.

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

The above embodiments are merely for illustrating the technical solutions of the present application and are not intended to limit the present application, and those skilled in the art can make various modifications and variations of the present application. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (24)

1. A pressure relief device for a battery cell, comprising:

a pressure relief body;

the pressure relief structure comprises a first mark engraving groove, a second mark engraving groove and a third mark engraving groove which are arranged on the pressure relief body, the first mark engraving groove and the third mark engraving groove are arranged at intervals, the first mark engraving groove and the third mark engraving groove are intersected with the second mark engraving groove, and the first mark engraving groove, the second mark engraving groove and the third mark engraving groove define a pressure relief portion together;

wherein the pressure relief portion is configured to open with the first, second, and third indenting grooves as boundaries when the pressure or temperature inside the battery cell reaches a threshold value, so as to relieve the pressure inside the battery cell.

2. The pressure relief device according to claim 1, wherein said first scored groove, said second scored groove, and said third scored groove together define two pressure relief portions, said two pressure relief portions being demarcated by said second scored groove.

3. The pressure relief device according to claim 2, wherein two pressure relief portions are symmetrically distributed on both sides of the second indent.

4. The pressure relief device according to claim 1, wherein said second score groove has a first weakened position, a second weakened position and a third weakened position, said second score groove intersects said first score groove at said first weakened position, said second score groove intersects said third score groove at said third weakened position, said second weakened position is located between said first weakened position and said third weakened position in the extending direction of said second score groove;

the pressure relief body is configured to rupture from the second weakened position to the first weakened position and the third weakened position at the second score groove and form a first fracture when the internal pressure or temperature of the battery cell reaches a threshold value, such that the pressure relief portion opens along the first score groove and the third score groove after the pressure relief body forms the first fracture.

5. The pressure relief device according to claim 4, wherein said pressure relief structure further comprises a fourth scored groove disposed on said pressure relief body, said fourth scored groove intersecting said second scored groove at said second weakened location.

6. The pressure relief device according to claim 5, wherein the depth of the first score groove, the depth of the second score groove, and the depth of the third score groove are each less than the depth of the fourth score groove.

7. The pressure relief device according to claim 6, wherein the depth of the first score groove and the depth of the third score groove are both equal to the depth of the second score groove.

8. The pressure relief device according to claim 5, wherein the depth of the first score groove and the depth of the third score groove are both less than the depth of a second score groove, the depth of the second score groove being equal to the depth of the fourth score groove.

9. The pressure relief device according to claim 8, wherein a depth of the first score groove is equal to a depth of the third score groove.

10. The pressure relief device according to claim 5, wherein the first score groove has a first end, the third score groove has a second end, the fourth score groove has a third end, and the first end, the second end, and the third end are located on the same side of the second score groove in a width direction of the second score groove;

the length of the first notching groove from the first end to the first weak position is a first length, the length of the third notching groove from the second end to the third weak position is a second length, the length of the fourth notching groove from the third end to the second weak position is a third length, and the third length is smaller than the first length and the second length.

11. The pressure relief device of claim 10, wherein said first length is equal to said second length.

12. The pressure relief device according to claim 5, wherein the first weak point is located at a midpoint of the first scored groove, the second weak point is located at a midpoint of the fourth scored groove, and the third weak point is located at a midpoint of the third scored groove;

the length of the fourth scoring groove is smaller than the length of the first scoring groove and the length of the third scoring groove.

13. The pressure relief device according to claim 12, wherein a length of the first score groove is equal to a length of the third score groove.

14. The pressure relief device according to claim 5, wherein said fourth score groove intersects and is disposed perpendicular to said second score groove.

15. The pressure relief device of claim 4, wherein the wall thickness of said pressure relief body at said first point of weakness and the wall thickness of said pressure relief body at said third point of weakness are each greater than the wall thickness of said pressure relief body at said second point of weakness.

16. The pressure relief device according to any of claims 1-15, wherein said second score groove has opposite fourth and fifth ends in the direction of extension of said second score groove, said first score groove being closer to said fourth end than said third score groove, said third score groove being closer to said fifth end than said first score groove;

the fourth end exceeds the first scoring groove along the direction of the first scoring groove back to the third scoring groove; and/or the fifth end exceeds the third scored groove along the direction of the third scored groove departing from the first scored groove.

17. The pressure relief device according to any of claims 1-15, wherein said pressure relief body is provided with a recess, and said pressure relief structure is disposed on a bottom surface of said recess.

18. The pressure relief device according to any of claims 1-15, wherein said pressure relief body has a receiving cavity formed therein for receiving an electrode assembly, said pressure relief body having a plurality of walls defining said receiving cavity, at least one wall being provided with said pressure relief structure.

19. The pressure relief device according to claim 18, wherein said pressure relief structure is disposed on an outer surface of said wall.

20. The pressure relief device according to claim 18, wherein said wall is provided with a recess recessed from an outer surface to an inner surface of said wall, said pressure relief structure being provided at a bottom surface of said recess.

21. A battery cell comprising a pressure relief device according to any of claims 1-20.

22. A battery, comprising:

the battery cell of claim 21; and

and the box body is used for accommodating the battery monomer.

23. An electrical device, comprising the battery of claim 22.

24. An apparatus for manufacturing a pressure relief device, the apparatus comprising:

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

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

the pressure relief structure comprises a first mark engraving groove, a second mark engraving groove and a third mark engraving groove which are arranged on the pressure relief body, the first mark engraving groove and the third mark engraving groove are arranged at intervals, the first mark engraving groove and the third mark engraving groove are intersected with the second mark engraving groove, the first mark engraving groove, the second mark engraving groove and the third mark engraving groove jointly define a pressure relief portion, and the pressure relief portion is configured to be opened by taking the first mark engraving groove, the second mark engraving groove and the third mark engraving groove as boundaries when the internal pressure or temperature of a battery monomer reaches a threshold value so as to relieve the internal pressure of the battery monomer.

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