CN217788574U - End cover, battery monomer, battery and consumer - Google Patents

Abstract

The application provides an end cover, a single battery, a battery and electric equipment, and relates to the field of batteries. The end cap includes a cap body and a reinforcement portion. The lid body has the pressure release district, and the protruding one side of locating the lid body in the thickness direction of rib, rib surround the pressure release district setting. The reinforcing part is arranged around the outer side of the pressure release area of the end cover, so that the strength of the pressure release area is enhanced, and the impact resistance of the pressure release area is improved. Like this, when the end cover receives external shock, the energy of external shock can be absorbed to the rib, reduces the size of transmitting the impact force to the pressure release district, avoids the pressure release district damaged because of receiving external shock to a certain extent, and then guarantees that the pressure release district can realize normal pressure release function, prevents also that the pressure release district opens promptly when free internal pressure of battery does not reach detonation pressure to guarantee the free normal work of battery.

Description

End cover, battery monomer, battery and consumer

Technical Field

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

Background

Batteries are widely used in new energy fields, such as electric vehicles, new energy vehicles and the like, and the new energy vehicles and the electric vehicles become new development trends of the automobile industry. And the end cover of the battery monomer is provided with a pressure relief structure for releasing the internal pressure when the internal pressure of the battery monomer reaches the detonation pressure. However, in the scenario of cell inversion, the pressure relief structure is often opened in advance, so that the normal pressure relief function cannot be realized.

SUMMERY OF THE UTILITY MODEL

An object of this application embodiment is to provide an end cover, battery monomer, battery and consumer, it aims at improving among the correlation technique pressure release structure and often opens in advance, leads to the problem that can not realize normal pressure release function.

In a first aspect, an embodiment of the present application provides an end cap, which includes a cap body and a reinforcing portion, where the cap body has a pressure relief area; the reinforcing part is arranged on one side of the cover body in the thickness direction in a protruding mode, and the reinforcing part is arranged around the pressure relief area.

In the technical scheme, the reinforcing part is arranged on the outer side of the pressure relief area of the end cover in a surrounding mode, so that the strength of the pressure relief area is enhanced, and the impact resistance of the pressure relief area is improved. Like this, when the end cover receives external shock, the energy of external shock can be absorbed to the rib, reduces the size of transmitting the impact force to the pressure release district, avoids the pressure release district damaged because of receiving external shock to a certain extent, and then guarantees that the pressure release district can realize normal pressure release function, prevents also that the pressure release district opens promptly when free internal pressure of battery does not reach detonation pressure to guarantee the free normal work of battery.

As an alternative solution to the embodiment of the present application, the reinforcing portion includes two first connecting segments and two second connecting segments, and in a circumferential direction of the pressure relief area, one first connecting segment, one second connecting segment, another first connecting segment, and another second connecting segment are sequentially connected end to form a closed structure; the two first connecting sections are oppositely arranged along a first direction, the two second connecting sections are oppositely arranged along a second direction, and the first direction is perpendicular to the second direction; wherein a dimension of the first connecting section in the first direction is larger than a dimension of the second connecting section in the second direction.

In above-mentioned technical scheme, two first linkage segments and two second linkage segments are located four different positions respectively, and two first linkage segments and two second linkage segments are connected and are formed enclosed construction, have stronger intensity, can effectively promote the shock resistance ability in pressure release district. In addition, because the size of the first connecting section in the first direction is larger than that of the second connecting section in the second direction, the size of the second connecting section in the first direction can be smaller than that of the first connecting section in the second direction, so that the reinforcing capacity of the first connecting section is equivalent to that of the second connecting section, the occupation of a reinforcing part on space is reduced, and the material waste is reduced.

As an optional technical solution of the embodiment of the present application, a size of the first connection section in the first direction is 5% to 35% of a size of the first connection section in the second direction.

In the above technical solution, when the size of the first connecting section in the first direction is less than 5% of the size of the first connecting section in the second direction, the reinforcing effect of the first connecting section is insufficient, and when the end cover is subjected to external impact, the energy of the external impact cannot be effectively absorbed. When the dimension of the first connecting section in the first direction is greater than 35% of the dimension of the first connecting section in the second direction, the volume occupied by the first connecting section is large, and after sufficient reinforcement has been achieved, the material is wasted by continuing to increase the dimension of the first connecting section in the first direction.

As an optional technical solution of the embodiment of the present application, a dimension of the second connection segment in the second direction is 5% to 30% of a dimension of the second connection segment in the first direction.

In the above technical solution, when the size of the second connecting section in the second direction is less than 5% of the size of the second connecting section in the first direction, the reinforcing effect of the second connecting section is insufficient, and when the end cap is subjected to external impact, the energy of the external impact cannot be effectively absorbed. When the dimension of the second connecting section in the second direction is greater than 30% of the dimension of the second connecting section in the first direction, the volume occupied by the second connecting section is large, and after sufficient reinforcement has been provided, the material is wasted by continuing to increase the dimension of the second connecting section in the second direction.

As an optional technical solution of the embodiment of the present application, the reinforcing portion includes at least one circular arc segment, and the first connecting segment and the second connecting segment are connected by one circular arc segment.

In the technical scheme, the first connecting section and the second connecting section are connected by arranging the arc sections, so that the stress concentration at the corners can be reduced, and the stress is optimized.

As an optional technical solution of the embodiment of the present application, a groove is provided at a position of the cover body corresponding to the reinforcing portion, the cover body has an inner surface and an outer surface opposite to each other in the thickness direction, the reinforcing portion is protrudingly provided on the inner surface, and the groove is recessed from the outer surface toward a direction close to the inner surface.

In the technical scheme, the grooves are formed in the outer surface of the cover body, so that the grooves have a thinning effect, and the thickness of the pressure relief area is reduced. When the internal pressure of the battery cell reaches the detonation pressure, the pressure relief area is more easily flushed away by the internal pressure, so that pressure relief is realized. The provision of the recess makes the relief area more easily flushable by internal pressure and also more easily flushable by external impact. Therefore, when the end cover receives external impact, the reinforcing part can absorb the energy of impact, reduces the size of the impact force transmitted to the pressure release area, so as to reduce the influence of the external impact on the pressure release area, avoid the pressure release area to be damaged due to the external impact to a certain extent, ensure the normal pressure release function, prevent that the pressure release area is opened when the internal pressure of the battery cell does not reach the detonation pressure, and ensure the normal work of the battery cell.

As an alternative to the embodiment of the present application, an inner side wall of the reinforcement portion defines a first space, and a side wall and a bottom wall of the groove define a second space, and the first space and the second space are located on both sides of the pressure relief area in the thickness direction.

In above-mentioned technical scheme, through making the pressure release district be located between first space and the second space, guarantee that the pressure release district is located the within range of recess, the attenuate effect of recess is better.

As an optional technical solution of the embodiment of the present application, the pressure relief area is provided with a pressure relief groove.

In the technical scheme, the pressure relief area is provided with the pressure relief groove, the thinning position is formed on the pressure relief area, and when the internal pressure of the battery monomer reaches the detonation pressure, the pressure relief area is convenient to open by taking the pressure relief groove as a boundary so as to relieve the internal pressure.

As an optional technical solution of the embodiment of the present application, the pressure relief groove is a closed groove extending along an end-to-end closed trajectory.

In above-mentioned technical scheme, through setting up the pressure release groove into the closed slot that extends along end to end's closed orbit, open the back at the pressure release district, the lid body can form great opening in the position that corresponds the pressure release district, improves pressure release efficiency.

As an alternative solution to the embodiment of the present application, the reinforcing portion and the pressure relief groove are respectively located on both sides of the pressure relief area in the thickness direction.

In the technical scheme, the reinforcing part is arranged on the side, far away from the pressure relief groove, of the pressure relief area, so that the processing and the manufacturing are convenient.

As an optional technical solution of the embodiment of the present application, the pressure relief groove includes a first groove section, a second groove section, a third groove section, and a fourth groove section, which are connected in sequence; the first groove section and the third groove section are oppositely arranged along a first direction, and the maximum distance between the first groove section and the third groove section is a first distance; in a second direction, the second groove segment and the fourth groove segment are oppositely arranged, and the minimum distance between the second groove segment and the fourth groove segment is a second distance; the second distance is greater than the first distance, and the first direction, the second direction and the thickness direction are perpendicular to each other.

In the technical scheme, the weak area formed on the pressure relief area by the boundaries of the first groove section, the second groove section, the third groove section and the fourth groove section is large, and is easy to be flushed away by internal pressure when the internal of the battery monomer reaches the initiation pressure, and the structure is simple and easy to mold and manufacture.

As an optional technical solution of the embodiment of the present application, the first groove section and the third groove section are linear grooves; and/or the second groove section and the fourth groove section are arc grooves.

In the technical scheme, the second groove section and the fourth groove section are arc grooves, the cover body forms a weak position at the middle position of the second groove section and the middle position of the fourth groove section, and the weak position is the first opening position of the pressure release area, so that the pressure release area can be opened in time when the inner part of the battery monomer reaches the detonation pressure. First groove section and third groove section are the straight line groove that extends along the width direction of lid body for first groove section and third groove section parallel arrangement, lid body crack open the back along second groove section and fourth groove section, can open along first groove section and third groove section more easily, improve the rate of opening of pressure release district, realize quick pressure release.

As an optional technical solution of the embodiment of the present application, the cover body partially protrudes along the thickness direction to form a convex portion, and the reinforcing portion is protruded on one side of the convex portion in the thickness direction.

In above-mentioned technical scheme, the lid body is local to be formed the convex part along the thickness direction protrusion of lid body, and the lid body will correspond with one side that the convex part is relative on its thickness direction and form sunken space, on the one hand, can hold the inside part of battery, is favorable to promoting the free energy density of battery, and on the other hand can improve the bending strength of end cover, improves the shock resistance of end cover.

In a second aspect, an embodiment of the present application further provides a battery cell, where the battery cell includes an electrode assembly, a case, and the above end cap; the case has an accommodation space having one end opened for accommodating the electrode assembly; the end cap is connected to the housing and closes the opening.

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

As an optional technical solution of the embodiment of the present application, the end cover is disposed on one side of the battery cell close to the bottom wall of the box body.

In above-mentioned technical scheme, through set up the end cover in the free one side that is close to the diapire of box of battery, be about to battery monomer inversion in the box.

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

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 structural diagram of a vehicle provided in some embodiments of the present application;

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

fig. 3 is a schematic structural diagram of a battery cell according to some embodiments of the present disclosure;

FIG. 4 is a schematic structural view of an end cap provided in accordance with some embodiments of the present application;

FIG. 5 is a schematic bottom view of an end cap provided in accordance with some embodiments of the present application;

FIG. 6 is a schematic top view of an end cap provided by some embodiments of the present application;

FIG. 7 is a cross-sectional view taken at the position C-C in FIG. 6;

FIG. 8 is an enlarged view of the location E in FIG. 7;

FIG. 9 is an enlarged view of position F of FIG. 6;

FIG. 10 is a schematic structural view of an end cap according to further embodiments of the present application;

FIG. 11 is a schematic top view of an end cap according to further embodiments of the present application;

fig. 12 is a sectional view taken at the position G-G in fig. 11.

Icon: 10-a box body; 11-a first part; 12-a second part; 20-a battery cell; 21-end cap; 211-a lid body; 2111-pressure relief zone; 2112-external surface; 2113-inner surface; 2114-a convex portion; 212-a reinforcement; 2121-first connection segment; 2122-a second connecting segment; 2123-arc segment; 2124-a first space; 213-pressure relief groove; 2131-a first groove segment; 2132-a second groove section; 2133-a third groove segment; 2134-a fourth groove segment; 214-a groove; 22-an electrode assembly; 23-a housing; 100-a battery; 200-a controller; 300-a motor; 1000-vehicle.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof in the description and claims of this application and the description of the figures above, are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "attached" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.

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

In the embodiments of the present application, like reference numerals denote like components, and in the different embodiments, detailed descriptions of the like components are omitted 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 this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of the present application is not limited thereto. 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 single battery of cylindricality battery, square battery monomer and laminate polymer battery monomer, this application embodiment is to this also not limited.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane. The single battery mainly depends on metal ions to move between the positive plate and the negative plate to work. The positive plate comprises a positive current collector and a positive active substance layer, wherein the positive active substance layer is coated on the surface of the positive current collector, the positive current collector which is not coated with the positive active substance layer protrudes out of the positive current collector which is coated with the positive active substance layer, and the positive current collector which is not coated with the positive active substance layer is used as a positive lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative plate comprises a negative current collector and a negative active substance layer, the negative active substance layer is coated on the surface of the negative current collector, the negative current collector which is not coated with the negative active substance layer protrudes out of the negative current collector which is coated with the negative active substance layer, and the negative current collector which is not coated with the negative active substance layer is used as a negative tab. The material of the negative electrode collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fuse is not fused when a large current is passed, a plurality of positive electrode tabs are stacked, and a plurality of negative electrode tabs are stacked. The material of the isolation film may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

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.

For the single battery, for guaranteeing the single security of battery, can set up pressure relief structure on the single end cover of battery, when the single internal pressure of battery reaches detonation pressure, pressure relief structure opens to the single internal pressure of battery is released, with the risk that reduces the single explosion of battery, catches fire.

The inventor notices that in a scene of cell inversion, the pressure relief structure is often opened in advance, so that a normal pressure relief function cannot be realized.

The inventor further studies and finds that, under the scene of electrical core inversion, the end cover is more easily impacted externally, and external impact force is easily transmitted to the position where the pressure relief structure is located, so that the pressure relief structure is opened in advance, and the normal pressure relief function cannot be realized.

In view of this, an embodiment of the present application provides an end cover, including a cover body and a reinforcing portion, the cover body has a pressure relief area, the reinforcing portion is disposed to protrude from one side of the cover body in a thickness direction, and the reinforcing portion is disposed around the pressure relief area.

The reinforcing part is arranged around the outer side of the pressure release area of the end cover, so that the strength of the pressure release area is enhanced, and the impact resistance of the pressure release area is improved. Like this, when the end cover receives external shock, the energy of external shock can be absorbed to the rib, reduces the size of the impact force of transmitting to the pressure release district, avoids the pressure release district to a certain extent because of receiving external shock damaged, and then guarantees that the pressure release district can realize normal pressure release function, prevents also that the pressure release district opens promptly when battery free internal pressure does not reach detonation pressure to guarantee battery free normal work.

The technical scheme described in the embodiment of the application is suitable for the battery and the electric equipment using the battery.

The electric equipment can be vehicles, mobile phones, portable equipment, notebook computers, ships, spacecrafts, electric toys, electric tools and the like. Spacecraft include aircraft, rockets, space shuttles, 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 description, the following embodiments will be described by taking an electric device as the vehicle 1000.

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

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

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

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

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

Referring to fig. 3, fig. 3 is an exploded schematic view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery 100. As shown in fig. 3, the battery cell 20 includes an end cap 21, an electrode assembly 22, a case 23, and other functional components.

The end cap 21 refers to a member that covers an opening of the case 23 to insulate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 23 to fit the housing 23. Alternatively, the end cap 21 may be made of a material (e.g., an aluminum alloy) having certain hardness and strength, so that the end cap 21 is not easily deformed when being extruded and collided, and the single battery 20 may have higher structural strength and improved safety performance. The end cap 21 may be provided with functional components such as electrode terminals (not shown in the drawings). The electrode terminals may be used to electrically connect with the electrode assembly 22 for outputting or inputting electric power of the battery cell 20. The material of the end cap 21 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate the electrical connection components within the housing 23 from the end cap 21 to reduce the risk of shorting. Illustratively, the insulator may be plastic, rubber, or the like.

The case 23 is an assembly for mating with the end cap 21 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to house the electrode assembly 22, electrolyte, and other components. The housing 23 and the end cap 21 may be separate components, and an opening may be formed in the housing 23, and the opening may be covered by the end cap 21 to form the internal environment of the battery cell 20. The end cap 21 and the housing 23 may be integrated, and specifically, the end cap 21 and the housing 23 may form a common connecting surface before other components are inserted into the housing, and when it is required to seal the inside of the housing 23, the end cap 21 covers the housing 23. The housing 23 may be of various shapes and various sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 23 may be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 23 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment.

The electrode assembly 22 is a component of the battery cell 20 in which electrochemical reactions occur. One or more electrode assemblies 22 may be contained within the case 23. The electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive and negative electrode sheets having the active material constitute the body portion of the electrode assembly 22, and the portions of the positive and negative electrode sheets having no active material each constitute a tab. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or at both ends of the main body portion, respectively. During the charge and discharge of the battery 100, the positive and negative active materials react with the electrolyte, and the tabs are connected to the electrode terminals to form a current loop.

Referring to fig. 4 and 5, fig. 4 is a schematic structural diagram of an end cap 21 according to some embodiments of the present disclosure. Fig. 5 is a schematic bottom view of an end cap 21 according to some embodiments of the present application. The embodiment of the application provides an end cover 21, and the end cover 21 comprises a cover body 211 and a reinforcing part 212. The cover body 211 has a relief area 2111, and the reinforcing portion 212 is provided protruding to one side of the cover body 211 in the thickness direction, and the reinforcing portion 212 is provided around the relief area 2111.

The cover body 211 is a main structure of the end cover 21, and is mainly used for closing the opening of the housing 23. The shape of the cover body 211 is adapted to the shape of the opening of the housing 23. For example, when the opening of the case 23 is rectangular, the cover body 211 is also rectangular. When the opening of the case 23 is circular, the shape of the cover body 211 is also circular.

The pressure relief area 2111 is an area of the lid body 211 that performs a pressure relief function. For example, the relief area 2111 may be an area of the end cap 21 where a burst disk is welded. For another example, the end cover 21 has a pressure relief groove 213 formed therein, and the pressure relief region 2111 may include a region inside the pressure relief groove 213 and a partial region outside the pressure relief groove).

The reinforcing portion 212 is a protruding structure that protrudes from one side of the cover body 211 in the thickness direction (D direction as shown in fig. 8) and is provided around the relief region 2111. The reinforcement portion 212 may be disposed on a surface of the cover body 211 facing the inside of the housing 23, or may be disposed on a surface of the cover body 211 facing away from the housing 23. Taking the cover body 211 as a rectangular flat plate structure as an example, the cover body 211 has an inner surface 2113 and an outer surface 2112 opposite to each other in the thickness direction, the inner surface 2113 of the cover body 211 faces the inside of the housing 23, the outer surface 2112 of the cover body 211 is disposed away from the housing 23, and the reinforcing portion 212 may be disposed on the inner surface 2113 of the cover body 211 or on the outer surface 2112 of the cover body 211.

The reinforcement 212 may be of various shapes. For example, the reinforcement portion 212 is formed in a racetrack shape, and the pressure relief region 2111 is a portion of the racetrack shape that is encircled by an inner race of the cap body 211. As another example, the reinforcement 212 encloses a rectangle. The relief area 2111 is a portion of the cover body 211 that is rectangular in shape. For another example, if the reinforcement portion 212 is a U-shaped protrusion extending along a U-shaped trajectory, the pressure relief area 2111 is a portion encircled by the U-shaped protrusion.

The reinforcing part 212 is arranged around the outer side of the pressure relief area 2111 of the end cover 21, so that the strength of the pressure relief area 2111 is enhanced, and the impact resistance of the pressure relief area 2111 is improved. Thus, when the end cap 21 is subjected to external impact, the reinforcing portion 212 can absorb energy of the external impact, reduce the magnitude of the impact force transmitted to the pressure relief area 2111, and prevent the pressure relief area 2111 from being damaged due to the external impact to a certain extent, thereby ensuring that the pressure relief area 2111 can realize a normal pressure relief function, that is, preventing the pressure relief area 2111 from being opened when the internal pressure of the battery cell 20 does not reach the initiation pressure, so as to ensure the normal operation of the battery cell 20.

Referring to fig. 5, in some embodiments, the reinforcing portion 212 includes two first connecting sections 2121 and two second connecting sections 2122. In the circumferential direction of the pressure relief area 2111, one first connecting section 2121, one second connecting section 2122, another first connecting section 2121 and another second connecting section 2122 are connected end to end in sequence to form a closed structure. The two first connecting sections 2121 are oppositely arranged in a first direction, and the two second connecting sections 2122 are oppositely arranged in a second direction, the first direction being perpendicular to the second direction. Wherein the size of the first connecting section 2121 in the first direction is larger than the size of the second connecting section 2122 in the second direction.

The two first connecting sections 2121 and the two second connecting sections 2122 are portions of the reinforcing portion 212 located at four different orientations, respectively. In the present embodiment, the two first connecting sections 2121 and the two second connecting sections 2122 are each a linear protrusion extending along a linear trajectory. The phrase "a first connecting section 2121, a second connecting section 2122, another first connecting section 2121 and another second connecting section 2122 are connected end to form a closed structure" includes that the tail end of one first connecting section 2121 is directly connected to the head end of one second connecting section 2122, and the tail end of one first connecting section 2121 is indirectly connected to the head end of another second connecting section 2122 through an intermediate structure. Similarly, the tail end of one second connecting segment 2122 may be directly connected to the head end of another first connecting segment 2121, or indirectly connected via an intermediate structure.

Since the first connecting section 2121 and the second connecting section 2122 are both linear protrusions, "two first connecting sections 2121 are oppositely arranged along a first direction (a direction shown in fig. 5) and two second connecting sections 2122 are oppositely arranged along a second direction (B direction shown in fig. 5)" may also be understood as two first connecting sections 2121 arranged in parallel in the first direction and two second connecting sections 2122 arranged in parallel in the second direction.

In the present embodiment, referring to fig. 5, the length of the first connecting section 2121 in the second direction (L1 shown in fig. 5) is greater than the length of the second connecting section 2122 in the first direction (L2 shown in fig. 5). Thus, the side of the second connecting portion 2122 is a short side of the reinforcing portion 212, and the side of the second connecting portion 2122 is a long side of the reinforcing portion 212. Because two corners of the short side are closer, the reinforcing effect can be achieved. If the dimension of the first connecting section 2121 in the first direction (D1 as shown in fig. 5) is equal to the dimension of the second connecting section 2122 in the second direction (D2 as shown in fig. 5), the reinforcing part 212 is reinforced to a greater extent at the short side and to a lesser extent at the long side.

In the present embodiment, by making the dimension D1 of the first connecting section 2121 in the first direction larger than the dimension D2 of the second connecting section 2122 in the second direction, the reinforcing part 212 is reinforced at the position of the short side to the position of the reinforcing part 212 at the long side.

The two first connecting sections 2121 and the two second connecting sections 2122 are located at four different positions, and the two first connecting sections 2121 and the two second connecting sections 2122 are connected to form a closed structure, so that the strength is high, and the impact resistance of the pressure relief area 2111 can be effectively improved. In addition, since the dimension D1 of the first connecting section 2121 in the first direction is greater than the dimension D2 of the second connecting section 2122 in the second direction, the dimension L2 of the second connecting section 2122 in the first direction can be smaller than the dimension L1 of the first connecting section 2121 in the second direction, so that the reinforcing capability of the first connecting section 2121 is equivalent to that of the second connecting section 2122, the occupation of space by the reinforcing part 212 is reduced, and the material waste is reduced.

In some embodiments, the dimension D1 of the first connecting section 2121 in the first direction is 5% to 35% of the dimension L1 of the first connecting section 2121 in the second direction.

In this embodiment, the first connecting section 2121 extends along the second direction, a dimension D1 of the first connecting section 2121 in the first direction is a width of the first connecting section 2121, and a dimension L1 of the first connecting section 2121 in the second direction is a length of the first connecting section 2121. The phrase "the dimension D1 of the first connecting section 2121 in the first direction is 5% to 35% of the dimension L1 of the first connecting section 2121 in the second direction" may also be understood as meaning that the width of the first connecting section 2121 is 5% to 35% of the length of the first connecting section 2121.

When the dimension of the first connecting section 2121 in the first direction D1 is less than 5% of the dimension L1 of the first connecting section 2121 in the second direction, the reinforcing function of the first connecting section 2121 is insufficient, and when the end cap 21 receives an external impact, the energy of the external impact cannot be effectively absorbed. When the dimension D1 of the first connecting section 2121 in the first direction is greater than 35% of the dimension L1 of the first connecting section 2121 in the second direction, the volume occupied by the first connecting section 2121 is large, and after sufficient reinforcing effect is provided, the material is wasted by further increasing the dimension D1 of the first connecting section 2121 in the first direction.

In some embodiments, the dimension D2 of the second connecting section 2122 in the second direction is 5% to 30% of the dimension L2 of the second connecting section 2122 in the first direction.

In this embodiment, the second connecting section 2122 extends along the first direction, a dimension D2 of the second connecting section 2122 in the second direction is a width of the second connecting section 2122, and a dimension L2 of the second connecting section 2122 in the first direction is a length of the second connecting section 2122. The phrase "the dimension D2 of the second connecting section 2122 in the second direction is 5% to 30% of the dimension L2 of the second connecting section 2122 in the first direction" can also be understood as meaning that the width of the second connecting section 2122 is 5% to 30% of the length of the second connecting section 2122.

When the dimension D2 of the second connecting section 2122 in the second direction is less than 5% of the dimension L2 of the second connecting section 2122 in the first direction, the reinforcing function of the second connecting section 2122 is insufficient, and when the end cap 21 receives an external impact, the energy of the external impact cannot be effectively absorbed. When the dimension D2 of the second connecting section 2122 in the second direction is greater than 30% of the dimension L2 of the second connecting section 2122 in the first direction, the volume occupied by the second connecting section 2122 is large, and after sufficient reinforcing effect is provided, the material is wasted by further increasing the dimension D2 of the second connecting section 2122 in the second direction.

Referring to fig. 5, in some embodiments, the reinforcing portion 212 includes at least one circular-arc segment 2123, and a first connecting segment 2121 and a second connecting segment 2122 are connected by the circular-arc segment 2123.

Circular arc segment 2123 is a convex structure extending along a circular arc trajectory. The reinforcement 212 may have one arc segment 2123, two arc segments 2123, three arc segments 2123, or four arc segments 2123. The first connecting section 2121 and the second connecting section 2122 are indirectly connected through the circular arc section 2123, so that circular arc transition is realized.

By providing the arc segment 2123 to connect the first connecting segment 2121 and the second connecting segment 2122, stress concentration at the corners can be reduced, and stress is optimized.

Referring to fig. 6, 7 and 8, fig. 6 is a schematic top view of an end cap 21 according to some embodiments of the present disclosure. Fig. 7 is a cross-sectional view taken at the position C-C in fig. 6. Fig. 8 is an enlarged view of the position E in fig. 7. In some embodiments, the cover body 211 is provided with a groove 214 at a position corresponding to the reinforcement 212. In the thickness direction, the cover body 211 has an inner surface 2113 and an outer surface 2112 opposed thereto. The reinforcement portion 212 is convex on the inner surface 2113, and the groove 214 is concave from the outer surface 2112 toward the inner surface 2113.

"the cover body 211 is provided with the groove 214 at a position corresponding to the reinforcing part 212" means that a projection of a contour of the groove 214 falls within a projection range of the reinforcing part 212 in the thickness direction.

The inner surface 2113 refers to the surface of the cover body 211 that is closer to the housing 23, and the outer surface 2112 refers to the surface of the cover body 211 that is farther from the housing 23.

The groove 214 refers to a slot-like structure that extends through the outer surface 2112 of the lid body 211 and in a direction from the outer surface 2112 toward the inner surface 2113. The shape of the groove 214 is not limited, and for example, the groove 214 may be rectangular or circular.

By providing the groove 214 in the outer surface 2112 of the cover body 211, the groove 214 is thinned, so that the thickness of the relief area 2111 is reduced. When the internal pressure of the battery cell 20 reaches the ignition pressure, the pressure relief region 2111 is more easily pushed away by the internal pressure, thereby achieving pressure relief. The provision of the groove 214 makes the relief area 2111 more easily flushable by internal pressure and also more easily flushable by external impact. Therefore, when the end cap 21 is subjected to external impact, the reinforcing portion 212 can absorb the energy of the impact, and reduce the magnitude of the impact force transmitted to the pressure relief region 2111, so as to reduce the influence of the external impact on the pressure relief region 2111, to a certain extent, prevent the pressure relief region 2111 from being damaged due to the external impact, and ensure that a normal pressure relief function can be realized.

Referring to fig. 8, in some embodiments, the inner sidewall of the reinforcement portion 212 defines a first space 2124, and the sidewall and the bottom wall of the groove 214 define a second space. The first space 2124 and the second space are located on both sides of the relief area 2111 in the thickness direction.

The first space 2124 is a space defined by an inner side wall of the reinforcing portion 212, and the first space 2124 is located on a side of the pressure relief region 2111 close to the reinforcing portion 212 in the thickness direction.

The second space is a space defined by the side wall and the bottom wall of the groove 214, in other words, the second space is an internal space of the groove 214. The second space is located on the side of the relief area 2111 away from the reinforcing portion 212 in the thickness direction. I.e. in the thickness direction, the first space 2124 and the second space are located on both sides of the pressure relief area 2111.

The thinning of groove 214 is enhanced by locating relief area 2111 between first space 2124 and the second space to ensure that relief area 2111 is within the confines of groove 214.

Referring to fig. 8, in some embodiments, the inner sidewall of the reinforcement portion 212 is disposed obliquely, and an obtuse angle is formed between the inner sidewall of the reinforcement portion 212 and the inner surface 2113. Thus, along the thickness direction, the first space 2124 gradually increases in the direction from the outer surface 2112 toward the inner surface 2113, facilitating avoidance of the electrode assembly 22.

In some embodiments, the outer sidewall of the reinforcement portion 212 is disposed at an angle, and the outer sidewall of the reinforcement portion 212 forms an obtuse angle with the inner surface 2113. In this way, when the width of the reinforcing portion 212 is ensured to be sufficient, the reinforcing portion 212 is ensured to occupy a small accommodation space surrounded by the cover body 211 and the housing 23.

Referring to fig. 8, in some embodiments, the pressure relief area 2111 is provided with a pressure relief groove 213.

The relief groove 213 may be a groove 214 recessed from the surface of the relief area 2111 in the thickness direction of the lid body 211. The relief groove 213 may be formed in a variety of ways, such as stamping, milling, etc. The pressure relief groove 213 may have various shapes, but the embodiment is not limited thereto. For example, the pressure relief groove 213 may be a groove 214 extending along a rectangular trajectory. The pressure relief groove 213 may also be a linear groove extending along the bent trajectory, and when the internal pressure of the battery cell 20 reaches the initiation pressure, the pressure relief region 2111 may be opened with the pressure relief groove 213 as a boundary to relieve the internal pressure of the battery cell 20.

By providing the relief groove 213 in the relief area 2111, a thinned portion is formed in the relief area 2111, and when the internal pressure of the battery cell 20 reaches the initiation pressure, the relief area 2111 is opened with the relief groove 213 as a boundary to relieve the internal pressure.

Referring to fig. 9, fig. 9 is an enlarged view of position F in fig. 6. In some embodiments, the pressure relief slots 213 are closed slots that extend in an end-to-end closed path.

The closed track is a track with two ends connected end to end, such as a rectangular track, an elliptical track and the like. In the case of molding the pressure relief groove 213 by milling, the cover body 211 may be machined along a closed trajectory to form the pressure relief groove 213.

In this embodiment, the pressure relief groove 213 is a closed groove, and after the pressure relief area 2111 is opened, the lid body 211 can form a large opening portion at a position corresponding to the pressure relief area 2111, thereby improving the pressure relief efficiency.

Referring to fig. 8 and 9, in some embodiments, the reinforcing portion 212 and the pressure relief groove 213 are respectively located on both sides of the pressure relief region 2111 in the thickness direction.

When the reinforcing portion 212 is provided to the inner surface 2113 of the cover body 211, the pressure relief groove 213 is provided to a side of the pressure relief region 2111 close to the outer surface 2112 of the cover body 211. When the reinforcing portion 212 is disposed on the outer surface 2112 of the cover body 211, the pressure relief groove 213 is disposed on the side of the pressure relief region 2111 close to the inner surface 2113 of the cover body 211.

By providing the reinforcing portion 212 on the side of the bleeder 2111 remote from the bleeder groove 213, manufacturing is facilitated.

Referring to fig. 9, in some embodiments, the pressure relief groove 213 includes a first groove segment 2131, a second groove segment 2132, a third groove segment 2133, and a fourth groove segment 2134 connected in sequence. In the first direction, the first and third trough segments 2131, 2133 are oppositely disposed, and the maximum distance between the first and third trough segments 2131, 2133 is a first distance. In the second direction, the second and fourth groove segments 2132, 2134 are oppositely disposed, and the minimum distance between the second and fourth groove segments 2132, 2134 is a second distance. The second distance is greater than the first distance, and the first direction, the second direction and the thickness direction are pairwise perpendicular.

The first, second, third and fourth trough sections 2131, 2132, 2133 and 2134 are respectively trough sections of the pressure relief trough 213 located in four different orientations. In this embodiment, the shapes of the first groove section 2131, the second groove section 2132, the third groove section 2133 and the fourth groove section 2134 are not particularly limited. For example, the first, second, third and fourth groove segments 2131, 2132, 2133 and 2134 may be straight grooves or circular grooves. If the first, second, third and fourth groove segments 2131, 2132, 2133 and 2134 are straight grooves, the first and third groove segments 2131 and 2133 may or may not be parallel, and the second and fourth groove segments 2132 and 2134 may or may not be parallel.

If the first and third segments 2131, 2133 are arranged in parallel, the maximum and minimum distances between the first and third segments 2131, 2133 are equal. If the second and fourth trough segments 2132, 2134 are arranged in parallel, the maximum and minimum distances between the second and fourth trough segments 2132, 2134 are equal.

The second and fourth groove sections 2132, 2134 are the short sides of the pressure relief groove 213, and the first and third groove sections 2131, 2133 are the long sides of the pressure relief groove 213.

In the present embodiment, the pressure relief area 2111 defined by the pressure relief groove 213 has a large pressure relief area, a simple structure, and is easy to mold and manufacture.

Referring to fig. 9, in some embodiments, the first and third slot segments 2131, 2133 are straight slots; and/or second groove segment 2132 and fourth groove segment 2134 are circular arc grooves.

The second and fourth groove segments 2132, 2134 may be curved in the same direction or in opposite directions. Second trough section 2132 and fourth trough section 2134 may be curved in a direction toward each other such that the center of second trough section 2132 and the center of fourth trough section 2134 are outside of pressure relief area 2111. Second trough section 2132 and fourth trough section 2134 may also be curved in a direction away from each other, with the center of circle of second trough section 2132 and the center of circle of fourth trough section 2134 being located within relief area 2111.

Illustratively, in fig. 9, the second and fourth groove segments 2132 and 2134 are curved away from each other, the first and third groove segments 2131 and 2133 are straight grooves extending in the second direction of the cover body 211, the first and third groove segments 2131 and 2133 are both tangent to the second groove segment 2132, the first and third groove segments 2131 and 2133 are both tangent to the fourth groove segment 2134, a distance from a middle position of the second groove segment 2132 to a middle position of the fourth groove segment 2134 in the second direction is a maximum distance between the second and fourth groove segments 2132 and 2134, and a length of the first groove segment 2131 is a minimum distance between the second and fourth groove segments 2132 and 2134.

In this embodiment, the second groove section 2132 and the fourth groove section 2134 are circular arc grooves, the cap body 211 forms a weak position in the middle of the second groove section 2132 and the middle of the fourth groove section 2134, and the weak position is the first opening position of the pressure relief area 2111, so that the pressure relief area 2111 can be opened in time when the initiation pressure is reached inside the battery cell 20. The first groove section 2131 and the third groove section 2133 are both straight grooves extending in the second direction, so that the first groove section 2131 and the third groove section 2133 are arranged in parallel, and after the cover body 211 is split along the second groove section 2132 and the fourth groove section 2134, the cover body can be opened along the first groove section 2131 and the third groove section 2133 more easily, so that the opening rate of the pressure relief area 2111 is increased, and quick pressure relief is realized.

Referring to fig. 10, 11 and 12, fig. 10 is a schematic structural view of an end cap 21 according to another embodiment of the present application. Fig. 11 is a schematic top view of an end cap 21 according to further embodiments of the present application. Fig. 12 is a sectional view taken at the position G-G in fig. 11. In other embodiments, the cover body 211 partially protrudes in the thickness direction to form a protrusion 2114, and the pressure relief groove 213 is provided in the protrusion 2114.

The cover body 211 partially protrudes along the thickness direction of the cover body 211 to form a protrusion 2114, and one side of the cover body 211 opposite to the protrusion 2114 in the thickness direction corresponds to form a concave space, so that on one hand, the cover body can accommodate the components inside the battery cell 20, which is beneficial to improving the energy density of the battery cell 20, and on the other hand, the cover body can improve the bending strength of the end cover 21 and the impact resistance of the end cover 21.

The embodiment of the present application further provides a battery cell 20, where the battery cell 20 includes an electrode assembly 22, a case 23, and the end cap 21. The case 23 has an accommodation space with one end open for accommodating the electrode assembly 22. The end cap 21 is attached to the housing 23 and closes the opening.

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

In some embodiments, the end cap 21 is disposed on a side of the battery cell 20 close to the bottom wall of the case 10.

The bottom wall of the housing 10 is the wall of the housing 10 opposite the open end of the housing 10.

The battery cell 20 is placed upside down in the case 10 by disposing the end cap 21 on the side of the battery cell 20 close to the bottom wall of the case 10.

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

Please refer to fig. 4-8 according to some embodiments of the present application.

The embodiment of the application provides an end cover 21, and the end cover 21 comprises a cover body 211 and a reinforcing part 212. The lid body 211 has a relief area 2111, and the reinforcing portion 212 is provided protruding to one side of the lid body 211 in the thickness direction, the reinforcing portion 212 being provided around the relief area 2111. The reinforcing portion 212 includes two first connecting segments 2121 and two second connecting segments 2122, and one first connecting segment 2121, one second connecting segment 2122, the other first connecting segment 2121 and the other second connecting segment 2122 are sequentially connected end to end along the circumferential direction of the bleeder area 2111 to form a closed structure. The two first connecting sections 2121 are oppositely arranged in the first direction, and the two second connecting sections 2122 are oppositely arranged in the second direction. The first direction is perpendicular to the second direction. Wherein a dimension D1 of the first connecting section 2121 in the first direction is greater than a dimension D2 of the second connecting section 2122 in the second direction. The dimension D1 of the first connecting section 2121 in the first direction is 5% to 35% of the dimension L1 of the first connecting section 2121 in the second direction. The dimension D2 of the second connecting section 2122 in the second direction is 5% to 30% of the dimension L2 of the second connecting section 2122 in the first direction.

The lid body 211 is provided with a groove 214 at a position corresponding to the reinforcing portion 212, the lid body 211 has an inner surface 2113 and an outer surface 2112 opposed to each other in the thickness direction, the reinforcing portion 212 is provided to protrude from the inner surface 2113, and the groove 214 is recessed from the outer surface 2112 in a direction close to the inner surface 2113. The inner side wall of the reinforcing portion 212 defines a first space 2124, and the side wall and the bottom wall of the groove 214 define a second space, and the first space 2124 and the second space are located on both sides of the pressure relief region 2111 in the thickness direction.

The reinforcing part 212 is arranged around the outer side of the pressure relief area 2111 of the end cover 21, so that the strength of the pressure relief area 2111 is enhanced, and the impact resistance of the pressure relief area 2111 is improved. Thus, when the end cap 21 is subjected to external impact, the reinforcing portion 212 can absorb energy of the external impact, reduce the magnitude of the impact force transmitted to the pressure relief area 2111, and prevent the pressure relief area 2111 from being damaged due to the external impact to a certain extent, thereby ensuring that the pressure relief area 2111 can realize a normal pressure relief function, i.e., preventing the pressure relief area 2111 from being opened when the internal pressure of the battery cell 20 does not reach the initiation pressure, so as to ensure the normal operation of the battery cell 20. The two first connecting sections 2121 and the two second connecting sections 2122 are located at four different positions respectively, and the two first connecting sections 2121 and the two second connecting sections 2122 are connected to form a closed structure, so that the strength is high, and the impact resistance of the pressure release area 2111 can be effectively improved. In addition, since the dimension D1 of the first connecting section 2121 in the first direction is greater than the dimension D2 of the second connecting section 2122 in the second direction, the dimension L2 of the second connecting section 2122 in the first direction can be smaller than the dimension L1 of the first connecting section 2121 in the second direction, so that the reinforcing capability of the first connecting section 2121 is equivalent to that of the second connecting section 2122, the occupation of space by the reinforcing part 212 is reduced, and the material waste is reduced.

When the dimension D1 of the first connecting section 2121 in the first direction is less than 5% of the dimension L1 of the first connecting section 2121 in the second direction, the reinforcing function of the first connecting section 2121 is insufficient, and when the end cap 21 receives an external impact, the energy of the external impact cannot be effectively absorbed. When the dimension D1 of the first connecting section 2121 in the first direction is greater than 35% of the dimension L1 of the first connecting section 2121 in the second direction, the volume occupied by the first connecting section 2121 is large, and after sufficient reinforcing effect is provided, the material is wasted by further increasing the dimension D1 of the first connecting section 2121 in the first direction. When the dimension D2 of the second connecting section 2122 in the second direction is less than 5% of the dimension L2 of the second connecting section 2122 in the first direction, the reinforcing effect of the second connecting section 2122 is insufficient, and when the end cap 21 receives an external impact, the energy of the external impact cannot be effectively absorbed. When the dimension D2 of the second connecting section 2122 in the second direction is greater than 30% of the dimension L2 of the second connecting section 2122 in the first direction, the volume occupied by the second connecting section 2122 is large, and after sufficient reinforcing effect has been provided, the further increase in the dimension D2 of the second connecting section 2122 in the second direction also causes waste of material.

By providing the groove 214 in the outer surface 2112 of the cover body 211, the groove 214 is thinned, so that the thickness of the relief area 2111 is reduced. When the internal pressure of the battery cell 20 reaches the ignition pressure, the pressure relief region 2111 is more easily pushed away by the internal pressure, thereby achieving pressure relief. The provision of the recess 214 makes the relief zone 2111 more easily broken by internal pressure and also more easily broken by external impact. Therefore, when the end cover 21 is subjected to external impact, the reinforcing portion 212 can absorb the energy of the impact, reduce the magnitude of the impact force transmitted to the pressure relief area 2111, reduce the influence of the external impact on the pressure relief area 2111, avoid the damage of the pressure relief area 2111 due to the external impact to a certain extent, and ensure that a normal pressure relief function can be realized. By having the pressure relief area 2111 between the first space 2124 and the second space, the pressure relief area 2111 is ensured to be within the range of the groove 214, and the thinning of the groove 214 is better.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, 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 (17)

1. An end cap, comprising:

a cover body having a pressure relief area;

and the reinforcing part is convexly arranged on one side of the cover body in the thickness direction and is arranged around the pressure relief area.

2. The end closure of claim 1, wherein said reinforcement portion comprises two first connecting segments and two second connecting segments, and one of said first connecting segments, one of said second connecting segments, the other of said first connecting segments and the other of said second connecting segments are sequentially connected end to end along a circumferential direction of said pressure relief area to form a closed structure;

the two first connecting sections are oppositely arranged along a first direction, the two second connecting sections are oppositely arranged along a second direction, and the first direction is perpendicular to the second direction;

wherein a dimension of the first connecting section in the first direction is larger than a dimension of the second connecting section in the second direction.

3. The end cap of claim 2, wherein a dimension of the first connection section in the first direction is 5% to 35% of a dimension of the first connection section in the second direction.

4. An end cap according to claim 2 or 3, wherein the dimension of the second connecting section in the second direction is 5% to 30% of the dimension of the second connecting section in the first direction.

5. An end cap according to claim 2 or 3, wherein the reinforcement comprises at least one circular arc segment, and one of the first and second connection segments is connected by one of the circular arc segments.

6. An end closure as claimed in claim 1, wherein said closure body is provided with a recess at a position corresponding to said reinforcing portion, said closure body having opposite inner and outer surfaces in said thickness direction, said reinforcing portion being provided convexly at said inner surface, said recess being recessed from said outer surface in a direction adjacent to said inner surface.

7. The end closure of claim 6, wherein an inner sidewall of the reinforcement portion defines a first space, wherein a sidewall and a bottom wall of the groove define a second space, and wherein the first space and the second space are located on opposite sides of the pressure relief region in the thickness direction.

8. The end closure of claim 1, wherein said pressure relief area is provided with a pressure relief groove.

9. An end closure as claimed in claim 8, in which the pressure relief groove is a closed groove extending along an end-to-end closed path.

10. An end closure according to claim 8 or 9, wherein said reinforcement portion and said pressure relief groove are located on both sides of the pressure relief region in said thickness direction, respectively.

11. An end cap according to claim 8 or 9, wherein the pressure relief groove comprises a first groove section, a second groove section, a third groove section and a fourth groove section connected in sequence;

the first groove section and the third groove section are oppositely arranged along a first direction, and the maximum distance between the first groove section and the third groove section is a first distance;

in a second direction, the second groove segment and the fourth groove segment are oppositely arranged, and the minimum distance between the second groove segment and the fourth groove segment is a second distance;

the second distance is greater than the first distance, and the first direction, the second direction and the thickness direction are perpendicular to each other.

12. The end cap of claim 11, wherein the first groove segment and the third groove segment are linear grooves; and/or

The second groove section and the fourth groove section are arc grooves.

13. The end cap according to claim 1, wherein the cap body is partially formed to be convex in the thickness direction, and the reinforcing portion is provided to be convex on one side of the convex in the thickness direction.

14. A battery cell, comprising:

an electrode assembly;

a case having an accommodation space with one end open for accommodating the electrode assembly;

the end cap of any of claims 1-13, attached to the housing and closing the opening.

15. A battery, comprising:

a box body;

the battery cell of claim 14, contained within the case.

16. The battery of claim 15, wherein the end cap is disposed on a side of the battery cell adjacent to a bottom wall of the case.

17. An electrical consumer, characterized in that it comprises a battery according to any of claims 15-16 for providing electrical energy.

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