CN217719868U - 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 pressure relief groove. The lid body has the pressure relief portion, and the pressure relief groove sets up in the lid body, and the pressure relief portion is defined out to the pressure relief groove. Wherein the pressure relief portion is curved in a thickness direction of the cover body. The pressure relief portion of this end cover is crooked along the thickness direction of lid body, when the end cover received external shock, the pressure relief portion can take place deformation along crooked direction, and then absorb external shock's energy, in order to reduce the external shock to the influence of pressure relief groove position on the lid body, avoid to a certain extent on the lid body the position at pressure relief groove position damaged because of receiving external shock, guarantee can realize normal pressure release function, also prevent that the pressure relief portion from opening when battery free internal pressure does not reach detonation pressure, in order to guarantee battery free normal work.

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 applied in the field of new energy resources, 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 a pressure relief structure for releasing the internal pressure when the internal pressure of the battery reaches the detonation pressure is arranged on the end cover of the battery. However, in a scenario of cell inversion, the pressure relief structure is often opened in advance, so that a 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 pressure relief groove, where the cap body has a pressure relief portion; the pressure relief groove is arranged on the cover body and defines the pressure relief part; wherein the pressure relief portion is curved in a thickness direction of the cover body.

In the technical scheme, the pressure relief portion of this end cover is crooked along the thickness direction of lid body, when the end cover received external shock, the pressure relief portion can take place deformation along crooked direction, and then absorb external shock's energy, in order to reduce the influence of external shock to the lid body on the pressure relief groove position, avoid to a certain extent on the lid body the position at pressure relief groove position damaged because of receiving external shock, guarantee to realize normal pressure release function, also prevent that the pressure relief portion from opening promptly when battery monomer's internal pressure does not reach detonation pressure, in order to guarantee battery monomer's normal work.

As an alternative to the embodiment of the present application, the cover body has an inner surface and an outer surface opposite to each other in the thickness direction, and the relief portion is curved in a direction in which the inner surface is directed to the outer surface.

In above-mentioned technical scheme, set up the bleeder part as the direction bending of following the directional surface of internal surface, also the bleeder part is crooked towards its opening direction, and when the end cover received external impact, the bleeder part took place deformation along opening direction, and the arch that the bleeder part deformation produced can not lead to the fact the influence to the electrode subassembly in the battery.

As an optional technical solution of the embodiment of the present application, along the thickness direction, the pressure relief portion has a first surface, the first surface and the pressure relief groove are located on the same side of the pressure relief portion, and the first surface is an arc surface.

In the technical scheme, the first surface is set to be the arc surface, so that the first surface is easy to deform when being impacted by the outside to absorb the energy of the impact of the outside and reduce the influence of the impact on the position of the pressure relief groove on the cover body.

As an optional technical solution of the embodiment of the present application, along the thickness direction, the relief portion has a second surface opposite to the first surface, the second surface is an arc surface, and bending directions of the first surface and the second surface are the same.

In the technical scheme, the second surface is also set to be the arc surface, the second surface is the same as the first surface in the bending direction, the pressure relief portion is made to form an arch structure, external impact is absorbed favorably, the position where the pressure relief groove is located on the cover body is prevented from being damaged due to external impact to a certain extent, the pressure relief portion is prevented from being opened when the internal pressure of the battery cell does not reach the detonation pressure, and the normal pressure relief function can be realized.

As an optional technical solution of the embodiment of the present application, in the thickness direction, the cover body has an inner surface and an outer surface which are opposite to each other, and a distance from the pressure relief portion to the inner surface in the thickness direction gradually increases from two ends of the pressure relief portion to an intermediate position along a first direction, where the first direction is perpendicular to the thickness direction.

In the above technical solution, in the thickness direction, both ends of the pressure relief portion in the first direction are closer to the inner surface than a middle position of the pressure relief portion in the first direction. That is, in the thickness direction, the intermediate position of the pressure relief portion in the first direction is farther away from the inner surface than both ends of the pressure relief portion in the first direction. The distance between the two ends of the pressure relief part and the inner surface in the thickness direction is gradually increased from the middle position to the middle position along the first direction, so that the section of a plane determined by the pressure relief part in the first direction and the thickness direction is in an arch shape, and the energy of external impact can be well absorbed.

As an optional technical solution of the embodiment of the present application, the end cap includes a first protruding portion, and the first protruding portion is convexly disposed on the outer surface and surrounds the pressure relief groove.

In the technical scheme, through set up the first bulge around the pressure relief groove on the end cover, when the end cover received external shock, first bulge can absorb the energy of impact, prevent that the impact force from transmitting to the position at pressure relief groove place, in order to reduce the external shock to the influence of pressure relief groove position on the lid body, avoid to a certain extent to cover the position at pressure relief groove place on the body damaged because of receiving external shock, prevent that the pressure relief portion opens promptly when free internal pressure of battery from not reaching detonation pressure, guarantee to realize normal pressure release function.

As an optional technical solution of the embodiment of the present application, the cover body is provided with a concave portion, the concave portion is recessed from the outer surface toward a direction close to the inner surface, and the pressure relief groove is provided at a bottom wall of the concave portion.

In the technical scheme, the concave part is formed in the end cover, and the pressure relief groove is formed in the bottom wall of the concave part, so that the concave part plays a role in thinning, and the thickness of the position where the pressure relief groove is formed in the cover body is further reduced. When the internal pressure of the battery reaches the detonation pressure, the position of the pressure relief groove on the cover body is more easily flushed away by the internal pressure, so that the pressure relief is realized.

As an optional technical solution of the embodiment of the present application, the end cap includes a first protruding portion, and the first protruding portion is convexly disposed on the bottom wall and surrounds the pressure relief groove.

In the technical scheme, the concave part enables the position of the pressure relief groove on the cover body to be easily flushed away by internal pressure, and meanwhile, the position of the pressure relief groove is easily flushed away by external impact. Consequently, through set up the first bulge around the pressure release groove on the diapire, when the end cover received external shock, first bulge can absorb the energy of impact, prevent that the impact force from transmitting to the position at pressure release groove place, in order to reduce the influence of external shock to the position at pressure release groove place on the lid body, avoid to a certain extent to cover the position at pressure release groove place on the body damaged because of receiving external shock, the pressure release portion opens promptly when also preventing that the free internal pressure of battery from not reaching detonation pressure, guarantee to realize normal pressure release function.

As an optional technical solution of the embodiment of the present application, the end cap includes a second protruding portion, the second protruding portion is protruding from the inner surface, and the second protruding portion corresponds to the position of the concave portion and is arranged around the pressure relief groove.

In the above technical scheme, the setting of concave part makes the position at concave part place receive external shock easily and warp, consequently, through set up on the inner surface with the corresponding second bulge that just encircles the pressure relief groove in concave part position, when the end cover received external shock, the energy of impact can be absorbed to the second bulge, prevent impact force transmission to the position at pressure relief groove place to a certain extent, in order to reduce the influence of external shock to pressure relief groove position on the lid body, avoid to a certain extent on the lid body pressure relief groove place position because of receiving external shock damaged.

As an optional technical solution of the embodiment of the present application, a length of the pressure relief portion in the second direction is greater than a length of the pressure relief portion in the first direction, and the first direction, the second direction, and the thickness direction are perpendicular to each other.

In the above technical solution, the length of the pressure relief portion in the second direction is greater than the length of the pressure relief portion in the first direction, so that the pressure relief portion is of an elongated structure. And, the cross-section at first direction and thickness direction place of pressure relief portion is the arch, and like this, the pressure relief portion can take place deformation when receiving external impact, and then absorbs the energy of impact well, avoids covering the position at pressure relief groove place on the body and damaged because of receiving external impact.

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 the technical scheme, the pressure relief groove is arranged to be the closed groove, so that when the internal pressure of the battery reaches the detonation pressure, the internal pressure can be rushed away from the position where the pressure relief groove is formed in the cover body all around, and the pressure relief is quicker and easier.

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; the second groove section and the fourth groove section are oppositely arranged along a second direction, and the minimum distance between the second groove section and the fourth groove section 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 above solution, the first distance is the maximum distance of the first and third groove segments in the first direction, and the second distance is the minimum distance of the second and fourth groove segments in the second direction. A minimum distance of the second slot segment and the fourth slot segment in the second direction is greater than a maximum distance of the first slot segment and the third slot segment in the first direction, indicating that a distance of the second slot segment and the fourth slot segment in the second direction is greater than a distance of the first slot segment and the third slot segment in the first direction.

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 first groove section and the third groove section are arranged to be the straight line grooves, the second groove section and the fourth groove section are arranged to be the arc grooves, stress concentration can be reduced, and when the internal pressure of the battery reaches the detonation pressure, the position of the pressure relief groove on the cover body is more easily flushed away by the internal pressure, so that pressure relief is realized.

As an optional technical solution of the embodiment of the present application, the cover body partially protrudes along the thickness direction to form a protrusion, and the pressure relief groove is disposed in the protrusion.

In above-mentioned technical scheme, the lid body is local to form the convex part along the thickness direction protrusion of lid body, and the lid body will correspond with the relative one side of convex part in its thickness direction and form the sunk space, on the one hand, can hold the inside part of battery monomer, 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 addition, because the pressure relief groove sets up the convex part, the pressure release portion of being convenient for in time opens the pressure release when battery monomer thermal runaway.

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 end cap, where the case has an accommodating space with an opening at one end, and the accommodating space is used 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 the technical scheme, the end cover is arranged on one side of the bottom wall, close to the box body, of the battery monomer, namely, the battery monomer is placed in the box body in an inverted mode.

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

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

FIG. 1 is a schematic 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 top view of an end cap provided by some embodiments of the present application;

FIG. 6 isbase:Sub>A cross-sectional view taken at location A-A of FIG. 5;

FIG. 7 is an enlarged view of position D of FIG. 6;

FIG. 8 is an enlarged view of position B of FIG. 5;

FIG. 9 is a cross-sectional view taken at the position C-C of FIG. 5;

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.

An 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-relief; 21111 — first surface; 21112-a second surface; 2112-external surface; 2113-inner surface; 2114-a convex portion; 212-relief groove; 2121-a first groove segment; 2122-a second groove section; 2123-a third groove segment; 2124-a fourth groove segment; 213-a first projection; 214-a recess; 215-a second projection; 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 herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the 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 foregoing 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 should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "attached" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; 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 charge or discharge of battery cells.

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

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.

To single battery, for guaranteeing the free security of battery, can set up pressure release structure on single end cover of battery, for example, set up pressure relief groove on the end cover, pressure relief groove inject pressure relief portion, and when single battery internal pressure reached detonation pressure, pressure relief portion opened to the pressure of single battery inside of releasing, in order to reduce single battery explosion, the risk of firing.

The inventor notices that in the scene of cell inversion, the pressure relief structure is often opened in advance, so that the 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, which includes a cover body and a pressure relief groove, where the pressure relief groove is disposed on the cover body, and the pressure relief groove defines a pressure relief portion. Wherein, the relief portion is bent in the thickness direction of the cover body.

Because the decompression portion of this end cover is crooked along the thickness direction of lid body, when the end cover received external shock, the decompression portion can take place deformation along crooked direction, and then absorb external shock's energy, in order to reduce the external shock to the influence of decompression groove position on the lid body, avoid to a certain extent on the lid body the position at decompression groove place damaged because of receiving external shock, guarantee to realize normal pressure release function, the decompression portion opens promptly when preventing also that the free internal pressure of battery from not reaching detonation pressure, in order to guarantee the free normal work of battery.

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

The electric equipment can be vehicles, mobile phones, portable equipment, notebook computers, ships, spacecrafts, electric toys, electric tools and the like. Spacecraft include aircraft, rockets, space shuttles, 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 a range-extended automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for 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 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 cells 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 one open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and second portions 11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

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

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

Referring to fig. 3, fig. 3 is an exploded 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 isolate 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 a certain hardness and strength, so that the end cap 21 is not easily deformed when being impacted, and the battery cell 20 may have a higher structural strength and improved safety. 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 also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. 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 short circuits. 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. Without limitation, 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 necessary to seal the interior 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., and the embodiment of the present invention is not limited thereto.

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 tabs having the active material constitute the body portions of the electrode assembly 22, and the portions of the positive and negative electrode tabs 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, 5, 6 and 7, fig. 4 is a schematic structural view of an end cap 21 according to some embodiments of the present application. Fig. 5 is a schematic top view of an end cap 21 provided in some embodiments of the present application. Fig. 6 isbase:Sub>A cross-sectional view taken atbase:Sub>A-base:Sub>A in fig. 5. Fig. 7 is an enlarged view of the position D in fig. 6. Some embodiments of the present disclosure provide an end cap 21, where the end cap 21 includes a cap body 211 and a pressure relief groove 212. The lid body 211 has a pressure relief portion 2111, the pressure relief groove 212 is disposed on the lid body 211, and the pressure relief groove 212 defines the pressure relief portion 2111. Wherein the relief portion 2111 is bent in the thickness direction of the cover body 211.

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 cover body 211 is also circular in shape.

The relief groove 212 may be formed in a variety of ways, such as punch forming, milling, etc. The pressure relief groove 212 may be provided on a surface of the cover body 211 facing the inside of the housing 23, or may be provided 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 pressure relief groove 212 may be disposed on the inner surface 2113 of the cover body 211 or may be disposed on the outer surface 2112 of the cover body 211.

The pressure relief groove 212 may be a groove recessed from the surface of the cap body 211 in the thickness direction (H direction as shown in fig. 7) of the cap body 211, and the pressure relief portion 2111 is a portion of the cap body 211 defined by the inner side surface of the groove. Taking the inner side surface of the concave groove as a rectangle for example, the pressure relief portion 2111 is a rectangular portion of the lid body 211 defined by the inner side surface of the pressure relief groove 212. The pressure relief groove 212 may also be a linear groove extending along a bending track, for example, the bending track is a U-shaped track, and the pressure relief portion 2111 is a U-shaped portion of the cover body 211 defined by the bending track. Further, for example, the bending locus is a rectangular locus, and the pressure relief portion 2111 is a rectangular portion of the cover body 211 defined by the bending locus. If the pressure relief groove 212 is a linear groove extending along the bent trajectory, the pressure relief portion 2111 may be opened with the pressure relief groove 212 as a boundary to relieve the pressure inside the battery cell 20 when the pressure inside the battery cell 20 reaches the initiation pressure.

"the pressure relief portion 2111 is curved in the thickness direction of the cap body 211" means that the middle portion of the pressure relief portion 2111 is convex outward or concave inward in the thickness direction of the cap body 211 with reference to the end portion of the pressure relief portion 2111 (the portion of the pressure relief portion 2111 near the pressure relief groove 212), so that the middle portion of the pressure relief portion 2111 is lower or higher than the end portion of the pressure relief portion 2111 in the thickness direction. Note that "the relief portion 2111 is curved in the thickness direction of the lid body 211" includes both that one surface of the relief portion 2111 in the thickness direction is curved in the thickness direction of the lid body 211, and that both surfaces of the relief portion 2111 in the thickness direction are curved in the thickness direction of the lid body 211.

This pressure relief portion 2111 of end cover 21 is crooked along the thickness direction of lid body 211, when end cover 21 receives external impact, pressure relief portion 2111 can take place deformation along crooked direction, and then absorb external impact's energy, in order to reduce the influence of external impact to the position of pressure relief groove 212 on lid body 211, avoid on lid body 211 to a certain extent that the position at pressure relief groove 212 place is damaged because of receiving external impact, guarantee to realize normal pressure release function, pressure relief portion 2111 opens promptly when preventing that battery cell 20's internal pressure from not reaching detonation pressure, in order to guarantee battery cell 20's normal work.

In some embodiments, the cover body 211 has opposing inner and outer surfaces 2113 and 2112 along the thickness direction, and the relief portion 2111 is curved in a direction in which the inner surface 2113 points toward the outer surface 2112.

In the thickness direction, the cover body 211 has an inner surface 2113 and an outer surface 2112 opposed to each other, wherein the inner surface 2113 is close to the case 23, the outer surface 2112 is away from the case 23, and the relief portion 2111 is curved in a direction in which the inner surface 2113 is directed toward the outer surface 2112.

The pressure relief portion 2111 is configured to be bent in a direction in which the inner surface 2113 is directed to the outer surface 2112, that is, the pressure relief portion 2111 is bent in the opening direction thereof, when the end cap 21 is subjected to an external impact, the pressure relief portion 2111 is deformed in the opening direction, a protrusion generated by the deformation of the pressure relief portion 2111 does not affect the electrode assembly 22 in the battery 100, and the electrode assembly 22 is prevented from being damaged when the pressure relief portion 2111 is deformed. In addition, the pressure relief portion 2111 is provided so as to be bent in the thickness direction toward the opening direction thereof, so that the occupation of the internal space (the space surrounded by the end cover 21 and the housing 23) of the battery cell 20 is reduced, which is advantageous for improving the energy density.

In other embodiments, along the thickness direction, relief portion 2111 is curved away from its opening direction. Thus, the pressure relief portion 2111 does not protrude from the outer surface 2112 of the cover body 211, and is less likely to cause stress concentration in other structures due to abutment with the other structures.

Referring to FIG. 7, in some embodiments, the relief portion 2111 has a first surface 21111 along the thickness direction, and the first surface 21111 and the relief groove 212 are on the same side of the relief portion 2111. The first surface 21111 is a circular arc surface.

Along the thickness direction, relief portion 2111 has first and second opposing surfaces 21111, 21112, wherein first surface 21111 is on the same side of relief portion 2111 as relief groove 212, and second surface 21112 is on opposite sides of relief portion 2111 as relief groove 212. Taking the case where the relief groove 212 is opened in the outer surface 2112 of the cover main body 211, the first surface 21111 is a surface of the relief portion 2111 away from the housing 23 in the thickness direction. For another example, if the pressure relief groove 212 is opened in the inner surface 2113 of the cover body 211, the first surface 21111 in the thickness direction is a surface of the pressure relief portion 2111 close to the housing 23.

The first surface 21111 is formed as an arc surface, so that it is easily deformed when being subjected to an external impact, to absorb energy of the external impact, and to reduce the influence of the external impact on the position of the pressure relief groove 212 on the cover body 211.

In other embodiments, the first surface 21111 is a curved surface extending along a parabolic trajectory.

In some embodiments, relief portion 2111 has a second surface 21112 opposite first surface 21111 in the thickness direction. The second surface 21112 is a circular arc surface, and the first surface 21111 and the second surface 21112 are curved in the same direction.

In the thickness direction, the first surface 21111 and the relief groove 212 are located on the same side of the relief portion 2111, and the second surface 21112 and the relief groove 212 are located on both sides of the relief portion 2111. Taking the case where the relief groove 212 is opened in the outer surface 2112 of the cover main body 211, the second surface 21112 is a surface of the relief portion 2111 close to the housing 23 in the thickness direction. For another example, if the pressure relief groove 212 is opened on the inner surface 2113 of the cover body 211, the second surface 21112 is a surface of the pressure relief portion 2111 away from the housing 23 in the thickness direction.

The second surface 21112 is also set to be an arc surface, and the bending direction of the second surface 21112 is the same as that of the first surface 21111, so that the pressure relief portion 2111 forms an arch structure, which is beneficial to absorbing external impact, the position of the pressure relief groove 212 on the cover body 211 is prevented from being damaged due to external impact to a certain extent, the pressure relief portion 2111 is prevented from being opened immediately when the internal pressure of the battery cell 20 does not reach the initiation pressure, and the normal pressure relief function is ensured.

In other embodiments, the second surface 21112 is planar, and the second surface 21112 is flush with the inner surface 2113 of the cap body 211. Thus, the first surface 21111 of the relief portion 2111 only needs to be machined to be an arc surface, which simplifies manufacturing and facilitates machining.

Referring to fig. 7, in some embodiments, the cap body 211 has an inner surface 2113 and an outer surface 2112 opposite to each other in the thickness direction. The distance in the thickness direction from the pressure-relief portion 2111 to the inner surface 2113 gradually increases from both ends of the pressure-relief portion 2111 to the intermediate position in the first direction. The first direction is perpendicular to 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 direction in which the inner surface 2113 is directed toward the outer surface 2112 is the opening direction of the relief portion 2111.

The first direction is perpendicular to the thickness direction, for example, referring to fig. 7, the first direction is the direction E shown in the figure.

In the first direction, both ends of the pressure relief portion 2111 are close to the pressure relief groove 212, and the middle position of the pressure relief portion 2111 is distant from the pressure relief groove 212.

"the distance in the thickness direction from both ends of the pressure relief portion 2111 to the inner surface 2113 gradually increases in the first direction" means that the distance in the thickness direction from the second surface 21112 of the pressure relief portion 2111 to the inner surface 2113 gradually increases from a position where the pressure relief portion 2111 is close to the pressure relief groove 212 to a position where the pressure relief portion 2111 is away from the pressure relief groove 212 in the first direction.

In the thickness direction, both ends of the pressure relief portion 2111 in the first direction are closer to the inner surface 2113 than the middle position of the pressure relief portion 2111 in the first direction. That is, in the thickness direction, the middle position of the pressure relief portion 2111 in the first direction is farther away from the inner surface 2113 than both ends of the pressure relief portion 2111 in the first direction. Since the distance from the pressure relief portion 2111 to the inner surface 2113 in the thickness direction gradually increases from both ends of the pressure relief portion 2111 to the middle position in the first direction, the cross section of the plane defined by the pressure relief portion 2111 in the first direction and the thickness direction is arcuate, and the energy of external impact can be absorbed well.

In some embodiments, the end cap 21 includes a first protrusion 213, and the first protrusion 213 protrudes from the outer surface 2112 and surrounds the pressure relief groove 212.

The first protrusion 213 is a protrusion protruding from the outer surface 2112 and surrounding the pressure relief groove 212. For example, the first protrusion 213 is formed in a racetrack shape, and the pressure relief groove 212 is located in the inner circle of the racetrack shape. As another example, the first protrusion 213 encloses a rectangle. The relief groove 212 is located inside the first protrusion 213. For another example, if the pressure relief groove 212 is a U-shaped groove extending along a U-shaped track, the first protrusion 213 may form a U-shaped protrusion extending along the U-shaped track, so that the pressure relief groove 212 is surrounded by the inner side of the first protrusion 213.

Through set up the first bulge 213 around pressure relief groove 212 on end cover 21, when end cover 21 received external impact, first bulge 213 can absorb the energy of impact, prevent that the impact force from transmitting to the position at pressure relief groove 212 place, in order to reduce the influence of external impact to pressure relief groove 212 position on lid body 211, avoid to a certain extent on lid body 211 pressure relief groove 212 position damaged because of receiving external impact, pressure relief portion 2111 opens promptly when preventing that battery cell 20's internal pressure from not reaching detonation pressure, guarantee to realize normal pressure release function.

In some embodiments, the end cap 21 includes a plurality of first protrusions 213, and the plurality of first protrusions 213 are protruded from the outer surface 2112 and are sequentially disposed around the outer circumference of the pressure relief groove 212. Through setting up a plurality of first bulges 213, promote the effect of absorbing impact energy, prevent that the impact force from transmitting to the position that the pressure relief groove 212 was located to reduce the influence of external impact to the position that pressure relief groove 212 was located on the lid body 211.

Referring to fig. 7, in some embodiments, the cover body 211 is provided with a recess 214, and the recess 214 is recessed from the outer surface 2112 to a direction close to the inner surface 2113. The pressure relief groove 212 is provided in the bottom wall of the recess 214.

The recess 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 recess 214 is not limited, and for example, the recess 214 may be rectangular or circular.

"the relief groove 212 is provided in the bottom wall of the recess 214" means that the relief groove 212 extends from the bottom wall, penetrates the bottom wall of the recess 214, and extends toward the inner surface 2113 in the thickness direction.

By forming the concave portion 214 in the end cap 21 and disposing the pressure relief groove 212 on the bottom wall of the concave portion 214, the concave portion 214 is thinned, so that the thickness of the cover body 211 at the position of the pressure relief groove 212 is further reduced. When the internal pressure of the battery 100 reaches the detonation pressure, the position of the pressure release groove 212 on the cap body 211 is more easily pushed away by the internal pressure, thereby achieving pressure release.

Referring to fig. 7, in some embodiments, the end cap 21 includes a first protrusion 213, and the first protrusion 213 is protruded from the bottom wall and surrounds the pressure relief groove 212.

The first protrusion 213 is a protrusion protruding from the bottom wall of the recess 214 and surrounding the pressure relief groove 212. For example, the first protrusion 213 is formed in a racetrack shape, and the pressure relief groove 212 is located in the inner circle of the racetrack shape. As another example, the first protrusion 213 encloses a rectangle. The relief groove 212 is located inside the first protrusion 213. For another example, if the pressure relief groove 212 is a U-shaped groove extending along a U-shaped track, the first protrusion 213 may form a U-shaped protrusion extending along the U-shaped track, so that the pressure relief groove 212 is surrounded by the inner side of the first protrusion 213.

The concave portion 214 is provided so that the position of the pressure relief groove 212 on the cover body 211 is more easily pushed away by the internal pressure and is also more easily pushed away by the external impact. Therefore, through set up the first bulge 213 around pressure relief groove 212 on the diapire, when end cover 21 received external shock, first bulge 213 can absorb the energy of impact, prevent that the impact force from transmitting to the position at pressure relief groove 212 place, in order to reduce the influence of external shock to the position at pressure relief groove 212 place on lid body 211, avoid lid body 211 to a certain extent on the position at pressure relief groove 212 place damaged because of receiving external shock, pressure relief portion 2111 opens promptly when preventing also that the internal pressure of battery cell 20 from not reaching detonation pressure, guarantee to realize normal pressure release function.

In some embodiments, the end cap 21 includes a plurality of first protrusions 213, and the plurality of first protrusions 213 are protruded from the bottom wall of the pressure relief groove 212 and sequentially surround the periphery of the pressure relief groove 212. By providing the plurality of first protrusions 213, the effect of absorbing impact energy is improved, and the impact force is prevented from being transmitted to the position of the pressure relief groove 212, so as to reduce the influence of external impact on the position of the pressure relief groove 212 on the cover body 211.

Referring to fig. 7, in some embodiments, the end cap 21 includes a second protrusion 215, and the second protrusion 215 is protruded from the inner surface 2113. The second projection 215 corresponds to the position of the recess 214 and is arranged around the relief groove 212.

The second protrusion 215 protrudes from the inner surface 2113, and it should be noted that the position of the second protrusion 215 protruding from the inner surface 2113 corresponds to the position of the recess 214, and the second protrusion 215 surrounds the pressure relief groove 212. Here, "the second projection 215 corresponds to the position of the recess 214" means that the projection of the contour of the recess 214 falls within the range of the projection of the second projection 215 in the thickness direction.

The second projecting portion 215 and the first projecting portion 213 are respectively located on both sides of the pressure relief portion 2111 in the thickness direction. The shape of the second projection 215 is adapted to the shape of the recess 214. For example, the concave portion 214 is a rectangular groove, and the second convex portion 215 encloses a rectangular structure.

The concave part 214 is arranged to make the position of the concave part 214 easy to be deformed by external impact, therefore, by arranging the second convex part 215 corresponding to the position of the concave part 214 and surrounding the pressure relief groove 212 on the inner surface 2113, when the end cover 21 is subjected to external impact, the second convex part 215 can absorb the impact energy, and prevent the impact force from being transmitted to the position of the pressure relief groove 212 to a certain extent, so as to reduce the influence of the external impact on the position of the pressure relief groove 212 on the cover body 211, and to a certain extent, avoid the position of the pressure relief groove 212 on the cover body 211 from being damaged by the external impact.

Referring to fig. 8, fig. 8 is an enlarged view of the position B in fig. 5. In some embodiments, the length of relief portion 2111 in the second direction is greater than the length of relief portion 2111 in the first direction, the second direction, and the thickness direction being perpendicular two by two.

Referring to fig. 8, the second direction is the direction F shown in fig. 8. Here, the length of the pressure relief portion 2111 in the second direction is greater than the length of the pressure relief portion 2111 in the first direction, so that the pressure relief portion 2111 extends in the second direction, being substantially elongated. It is understood that the second direction refers to the lengthwise direction of the pressure relief portion 2111, and the first direction refers to the widthwise direction of the pressure relief portion 2111, the thickness direction of the pressure relief portion 2111 being the same as the thickness direction of the cover body 211.

The length of the relief portion 2111 in the second direction is greater than its length in the first direction, so that the relief portion 2111 has an elongated structure. Moreover, the cross section of the pressure relief portion 2111 in the first direction and the thickness direction is arched, so that the pressure relief portion 2111 can deform when being subjected to external impact, thereby absorbing the impact energy well and avoiding the damage of the position of the pressure relief groove 212 on the cover body 211 due to the external impact.

Referring to fig. 8, in some embodiments, the pressure relief groove 212 is a closed groove extending along a closed trajectory.

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 forming the relief groove 212 by milling, for example, the cover body 211 may be machined along a closed trajectory to form the relief groove 212.

In the present embodiment, the pressure relief groove 212 is a closed groove, and after the pressure relief portion 2111 is opened, the lid body 211 can form a large opening portion at a position corresponding to the pressure relief portion 2111, thereby improving the pressure relief efficiency.

Referring to fig. 8, in some embodiments, the pressure relief groove 212 includes a first groove segment 2121, a second groove segment 2122, a third groove segment 2123, and a fourth groove segment 2124 connected in series. In the first direction, the first and third groove sections 2121 and 2123 are oppositely arranged, and the maximum distance between the first and third groove sections 2121 and 2123 is a first distance. In the second direction, the second and fourth groove segments 2122 and 2124 are oppositely disposed, and the minimum distance between the second and fourth groove segments 2122 and 2124 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 groove sections 2121, 2122, 2123 and 2124 are the groove sections of the pressure relief groove 212 at four different orientations, respectively. In the present embodiment, the shapes of the first, second, third, and fourth groove sections 2121, 2122, 2123, and 2124 are not particularly limited. For example, the first, second, third and fourth groove sections 2121, 2122, 2123 and 2124 may be straight grooves or arc grooves. If the first, second, third and fourth slot segments 2121, 2122, 2123 and 2124 are straight slots, the first and third slot segments 2121, 2123 may or may not be parallel, and the second and fourth slot segments 2122, 2124 may or may not be parallel.

If the first and third slot segments 2121 and 2123 are arranged in parallel, the maximum distance between the first and third slot segments 2121 and 2123 is equal to the minimum distance. If the second slot segment 2122 and the fourth slot segment 2124 are disposed in parallel, the maximum distance between the second slot segment 2122 and the fourth slot segment 2124 is equal to the minimum distance.

The second and fourth groove sections 2122 and 2124 are short sides of the pressure relief groove 212, and the first and third groove sections 2121 and 2123 are long sides of the pressure relief groove 212.

In the present embodiment, the pressure relief portion 2111 defined by the pressure relief groove 212 has a large pressure relief area, a simple structure, and is easy to mold and manufacture.

Referring to fig. 8, in some embodiments, the first slot segment 2121 and the third slot segment 2123 are straight slots; and/or the second and fourth groove segments 2122, 2124 are circular arc grooves.

The second and fourth slot segments 2122, 2124 may be curved in the same direction or in opposite directions. The second groove section 2122 and the fourth groove section 2124 may be curved in a direction approaching each other such that a center of the second groove section 2122 and a center of the fourth groove section 2124 are located outside the pressure relief portion 2111. The second slot segment 2122 and the fourth slot segment 2124 may also be curved away from each other, and the center of the second slot segment 2122 and the center of the fourth slot segment 2124 are located inside the pressure relief portion 2111.

Illustratively, in fig. 8, the second and fourth slot segments 2122 and 2124 are curved away from each other, the first and third slot segments 2121 and 2123 are straight slots extending in the second direction of the cover body 211, the first and third slot segments 2121 and 2123 are each tangent to the second slot segment 2122, and the first and third slot segments 2121 and 2123 are each tangent to the fourth slot segment 2124, a distance from a middle position of the second slot segment 2122 to a middle position of the fourth slot segment 2124 in the second direction is a maximum distance between the second and fourth slot segments 2122 and 2124, and a length of the first slot segment 2121 is a minimum distance between the second and fourth slot segments 2122 and 2124.

In this embodiment, the second groove section 2122 and the fourth groove section 2124 are circular arc grooves, the cover body 211 forms a weak position at the middle position of the second groove section 2122 and the middle position of the fourth groove section 2124, and the weak position is the first opening position of the pressure relief portion 2111, so that the pressure relief portion 2111 can be opened in time when the initiation pressure is reached inside the battery cell 20. The first groove section 2121 and the third groove section 2123 are linear grooves extending along the second direction, so that the first groove section 2121 and the third groove section 2123 are arranged in parallel, and after the cover body 211 is split along the second groove section 2122 and the fourth groove section 2124, the cover body 211 can be opened along the first groove section 2121 and the third groove section 2123 more easily, so that the opening rate of the pressure relief portion 2111 is increased, and rapid pressure relief is realized.

Referring to fig. 9, fig. 9 is a cross-sectional view taken at a position C-C in fig. 5. In some embodiments, the middle portion of the pressure relief portion 2111 is straight in the second direction, and both ends of the pressure relief portion 2111 have a circular arc segment that is curved away from the opening direction (when the pressure relief groove 212 is taken as a reference, the circular arc segment is a circular arc segment that is curved in the opening direction when the middle portion of the pressure relief portion 2111 is taken as a reference), and both ends of the pressure relief portion 2111 are respectively connected to the pressure relief groove 212. The length of the circular arc segment in the second direction matches the length of the second slot segment 2122 in the second direction. The length of the straight portion of the middle portion of the relief portion 2111 matches the length of the first groove section 2121 in the second direction.

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 212 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. In addition, since the pressure relief groove 212 is disposed on the protrusion 2114, the pressure relief portion 2111 is opened to relieve pressure in time when the battery cell 20 is thermally out of control.

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 near 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. 4-7 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 pressure relief groove 212, wherein the cover body 211 is provided with a pressure relief portion 2111. The pressure relief groove 212 is disposed on the cover body 211, and the pressure relief portion 2111 is defined by the pressure relief groove 212. Wherein the relief portion 2111 is bent in the thickness direction of the cover body 211. In the thickness direction, the relief portion 2111 is bent toward the opening direction thereof. In the thickness direction, the pressure relief portion 2111 has a first surface 21111, the first surface 21111 and the pressure relief groove 212 are located on the same side of the pressure relief portion 2111, and the first surface 21111 is an arc surface. In the thickness direction, the relief portion 2111 has a second surface 21112 opposed to the first surface 21111, the second surface 21112 being an arc surface, the first surface 21111 and the second surface 21112 being curved in the same direction. The lid body 211 is provided with a recess 214, the recess 214 is recessed from the outer surface 2112 in a direction close to the inner surface 2113, and the pressure relief groove 212 is provided in the bottom wall of the recess 214. The end cap 21 includes a first protrusion 213, and the first protrusion 213 is protruded from the bottom wall and surrounds the pressure relief groove 212.

This pressure relief portion 2111 of end cover 21 is crooked along the thickness direction of lid body 211, when end cover 21 receives external shock, deformation can take place along crooked direction for pressure relief portion 2111, and then absorb external shock's energy, in order to reduce the influence of external shock to the position of pressure relief groove 212 on the lid body 211, avoid to a certain extent on the lid body 211 the position at pressure relief groove 212 place damaged because of receiving external shock, guarantee to realize normal pressure release function, pressure relief portion 2111 opens promptly when preventing that the internal pressure of battery cell 20 from not reaching initiation pressure promptly, in order to guarantee the normal work of battery cell 20. The pressure relief portion 2111 is arranged to be bent in the thickness direction toward the opening direction thereof, and when the end cap 21 is subjected to an external impact, the pressure relief portion 2111 is deformed in the opening direction, and the protrusion resulting from the deformation of the pressure relief portion 2111 does not affect the electrode assembly 22 in the battery 100. The first surface 21111 and the second surface 21112 are provided as arc surfaces, so that they are easily deformed when being subjected to external impact to absorb energy of the external impact, thereby reducing the influence of the external impact on the position of the pressure relief groove 212 on the cover body 211.

By forming the concave portion 214 in the end cap 21 and disposing the pressure relief groove 212 on the bottom wall of the concave portion 214, the concave portion 214 is thinned, so that the thickness of the cover body 211 at the position of the pressure relief groove 212 is further reduced. When the internal pressure of the battery 100 reaches the detonation pressure, the position of the pressure relief groove 212 on the cap body 211 is more easily pushed away by the internal pressure, thereby achieving pressure relief. The concave portion 214 is provided so that the position of the pressure relief groove 212 on the cover body 211 is more easily pushed away by the internal pressure and is also more easily pushed away by the external impact. Therefore, through set up the first bulge 213 around pressure relief groove 212 on the diapire, when end cover 21 received external impact, first bulge 213 can absorb the energy of impact, prevents that the impact force from transmitting to the position at pressure relief groove 212 place to reduce the external impact to the influence of pressure relief groove 212 position on lid body 211, avoid on the lid body 211 pressure relief groove 212 position damaged because of receiving external impact, guarantee to realize normal pressure relief function.

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 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 (18)

1. An end cap, comprising:

a lid body having a relief portion;

the pressure relief groove is arranged on the cover body and defines the pressure relief part;

wherein the pressure relief portion is curved in a thickness direction of the cover body.

2. An end closure according to claim 1, wherein said closure body has opposite inner and outer surfaces in said thickness direction, said relief portion being curved in a direction in which said inner surface is directed toward said outer surface.

3. An end closure according to claim 1 or claim 2, wherein said relief portion has a first surface along said thickness direction, said first surface and said relief groove being located on the same side of said relief portion, said first surface being a circular arc.

4. An end closure according to claim 3, wherein said relief portion has a second surface opposite said first surface in said thickness direction, said second surface being an arc surface, said first and second surfaces being curved in the same direction.

5. An end closure according to claim 4, wherein said closure body has opposite inner and outer surfaces in said thickness direction, and wherein said relief portion has a distance in said thickness direction from said inner surface gradually increasing from both ends of said relief portion to an intermediate position in a first direction perpendicular to said thickness direction.

6. The end cap of claim 5, wherein the end cap includes a first protrusion protruding from the outer surface and surrounding the pressure relief groove.

7. An end cap according to claim 5, wherein the cap body is provided with a recess recessed from the outer surface in a direction close to the inner surface, and the pressure relief groove is provided in a bottom wall of the recess.

8. The end cap of claim 7, wherein the end cap includes a first protrusion protruding from the bottom wall and surrounding the pressure relief groove.

9. The end cap of claim 7, wherein the end cap includes a second projection projecting from the inner surface, the second projection corresponding to the location of the recess and being disposed around the relief groove.

10. An end cap according to any of claims 5 to 9 wherein the length of the vent portion in a second direction is greater than the length of the vent portion in the first direction, the second direction and the thickness direction being perpendicular in pairs.

11. An end closure as claimed in claim 1, in which the pressure relief groove is a closed groove extending along an end-to-end closed path.

12. The end cap of claim 11, wherein the pressure relief groove comprises a first groove segment, a second groove segment, a third groove segment, and a fourth groove segment connected in series;

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;

the second groove section and the fourth groove section are oppositely arranged along a second direction, and the minimum distance between the second groove section and the fourth groove section 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.

13. The end cap of claim 12, wherein the first and third channel segments are linear channels; and/or

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

14. The end cap according to claim 1, wherein the cap body is partially formed to be convex in the thickness direction, and the pressure relief groove is provided in the convex portion.

15. 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 1-14, attached to the housing and closing the opening.

16. A battery, comprising:

a box body;

the battery cell of claim 15, contained within the case.

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

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

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