CN217158556U

CN217158556U - Battery monomer, battery and consumer

Info

Publication number: CN217158556U
Application number: CN202221039621.7U
Authority: CN
Inventors: 谷慧; 孙东升; 金海族
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-04-29
Filing date: 2022-04-29
Publication date: 2022-08-09
Anticipated expiration: 2032-04-29

Abstract

The embodiment of the application provides a single battery, a battery and electric equipment, and belongs to the technical field of batteries. The battery cell includes a case, an electrode assembly, an end cap, and a current collecting member. The housing has an opening. The electrode assembly is housed in the case. The end cap is connected to the housing and closes the opening. The current collecting member is located in the case, the current collecting member is disposed at a side of the electrode assembly facing the end cap, and the current collecting member connects the end cap and the electrode assembly. The end cover comprises a connecting part connected with the current collecting component, a containing groove is formed in the surface, facing the end cover, of the current collecting component along the thickness direction of the end cover, and the connecting part is at least partially contained in the containing groove. The holding tank can dodge the space for connecting portion provide to reduce connecting portion and be connected the back at end cover and casing and to the extrusion force of collecting the flow component, reduce the deflection of collecting the flow component, reduce the extrusion force that the collecting the flow component received connecting portion and the deflection is too big, cause collecting the flow component and be connected the risk of losing efficacy with electrode subassembly, improved the stability that end cover and electrode subassembly are connected electrically.

Description

Battery monomer, battery and consumer

Technical Field

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

Background

With the development of new energy technology, batteries are more and more widely used, for example, in mobile phones, notebook computers, battery cars, electric automobiles, electric airplanes, electric steamships, electric toy cars, electric toy steamships, electric toy airplanes, electric tools, and the like.

The battery cell serves as an energy storage element, and generally, an electrode assembly and an electrolyte chemically react with each other to output electric energy. In the single battery, the end cover and the electrode assembly can be electrically connected through the current collecting member, and in order to ensure the normal use of the single battery, the stability of the electrical connection between the end cover and the electrode assembly needs to be ensured. Therefore, how to improve the stability of the electrical connection between the end cap and the electrode assembly is a problem to be solved in the battery technology.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a battery monomer, battery and consumer, can effectively improve the stability problem that end cover and electrode subassembly electricity are connected.

In a first aspect, embodiments of the present application provide a battery cell, including a case, an electrode assembly, an end cap, and a current collecting member; the shell is provided with an opening; the electrode assembly is accommodated in the case; the end cover is connected with the shell and closes the opening; the current collecting component is positioned in the shell, the current collecting component is arranged on one side of the electrode component facing the end cover, and the current collecting component is connected with the end cover and the electrode component; the end cover comprises a connecting part connected with the current collecting component, a containing groove is formed in the surface, facing the end cover, of the current collecting component in the thickness direction of the end cover, and the connecting part is at least partially contained in the containing groove.

Among the above-mentioned technical scheme, the connecting portion that end cover and mass flow component are connected are partly held in the holding tank at least, and the holding tank can provide the space of dodging for connecting portion, and the position that the end cover is holding the groove in setting up can form the stress buffer to reduce the extrusion force of connecting portion to the mass flow component after end cover and casing are connected, reduce the deflection of mass flow component, reduce the mass flow component and receive the extrusion force of connecting portion and the deflection is too big, cause mass flow component and electrode subassembly to be connected the risk of losing efficacy, improved the stability that end cover and electrode subassembly are connected electrically.

In some embodiments, the receiving slots are closed slots extending circumferentially of the current collecting member and connected end to end. The holding tank of this kind of structure has better adaptability to connecting portion, and connecting portion lie in different position on the circumference of end cover and all can hold in the holding tank, reduces the installation degree of difficulty of end cover.

In some embodiments, the receiving groove is an annular groove. Annular holding tank simple structure, easily shaping.

In some embodiments, the receiving groove has a first groove bottom surface and a first groove side surface, the first groove side surface being contiguous with the first groove bottom surface; the first groove bottom faces the connecting part along the thickness direction; along a first direction, the side surface of the first groove is positioned at the inner side of the connecting part, and the first direction is vertical to the thickness direction; wherein the angle between the first groove side surface and the first groove bottom surface is theta ₁ And satisfies the following conditions: theta is less than 90 DEG ₁ < 180 deg. The side surface of the first groove positioned at the inner side of the connecting part is arranged at an obtuse angle with the bottom of the first groove, the side surface of the first groove is in an inclined state, and the first groove is positioned at the bottom of the first grooveThe groove side surface plays a guiding role for the connecting part, so that the connecting part can enter the accommodating groove more easily, and the mounting efficiency of the end cover is improved.

In some embodiments, the receiving groove further includes a second groove side surface connected to the first groove bottom surface, the first groove side surface being located outside the connecting portion in the first direction; wherein the angle between the second groove side surface and the first groove bottom surface is theta ₂ And satisfies the following conditions: theta is less than 90 DEG ₂ < 180 deg. The second groove side face located on the outer side of the connecting portion and the bottom of the first groove are arranged in an obtuse angle mode, the second groove side face is in an inclined state, the second groove side face plays a role in guiding the connecting portion, the connecting portion can enter the containing groove easily, and the installing efficiency of the end cover is improved.

In some embodiments, the first and second slot sides are each spaced from the web in the first direction. In this way, the gap between the first and second slot sides is greater than the width of the portion of the connecting portion located within the receiving groove, on the one hand, so that the connecting portion enters the receiving groove more easily, and on the other hand, the risk that the connecting portion applies a pressing force to the first and second slot sides, thereby increasing the amount of deformation of the current collecting member, is reduced.

In some embodiments, the receiving groove has a first groove bottom surface and a second groove side surface, the second groove side surface being contiguous with the first groove bottom surface; the first groove bottom faces the connecting part along the thickness direction; the second groove side surface is positioned on the outer side of the connecting part along a first direction, and the first direction is perpendicular to the thickness direction; wherein the angle between the second groove side surface and the first groove bottom surface is theta ₂ And satisfies the following conditions: theta is less than 90 DEG ₂ < 180 deg. The second groove side face located on the outer side of the connecting portion and the bottom of the first groove are arranged in an obtuse angle mode, the second groove side face is in an inclined state, and the second groove side face plays a role in guiding the connecting portion, so that the connecting portion can enter the accommodating groove more easily.

In some embodiments, the receiving groove includes a first groove side surface and a second groove side surface, the first groove side surface and the second groove side surface are respectively located at both sides of the connecting portion along a first direction, and the first direction is perpendicular to the thickness direction; the distance between the first groove side surface and the second groove side surface in the first direction is gradually reduced along the depth direction of the accommodating groove. Thus, the width of the accommodating groove is gradually narrowed from the opening position thereof in the depth direction, so that the connecting portion can more easily enter the accommodating groove.

In some embodiments, the current collecting member includes a first connection region and a second connection region; the first connecting area is connected with the connecting part, and the position of the current collecting component provided with the accommodating groove forms the first connecting area; the second connection region is connected to the electrode assembly; wherein projections of the first connection region and the second connection region on a plane perpendicular to the thickness direction do not overlap. The structure enables the first connecting area and the second connecting area to be arranged in a staggered mode, the first connecting area and the second connecting area are not affected mutually, the connection between the first connecting area and the connecting portion does not affect the connection between the second connecting area and the electrode assembly, and the stability of connection between the current collecting component and the electrode assembly is improved.

In some embodiments, the first connection region is circumferentially disposed outside the second connection region. This configuration allows the first connection region to have a large size, enabling an increase in the flow area of the current collecting member and the end cap.

In some embodiments, the thickness of the second connection region is L, and the depth of the receiving groove is H, such that: H/L is more than or equal to 0.15 and less than 1. The ratio of the depth of the accommodating groove to the thickness of the second connecting area is set within a reasonable range, so that the depth of the accommodating groove cannot be too small to accommodate more parts of the connecting part, and the deformation of the current collecting member is reduced.

In some embodiments, the receiving groove has a first groove bottom surface, and the connecting portion abuts against the first groove bottom surface along the thickness direction. This structure increases the contact area of the connecting portion with the current collecting member, thereby increasing the flow area of the current collecting member with the end cap.

In some embodiments, the current collecting member is welded to the connection portion. The current collecting component is firmly connected with the connecting part, and stable overcurrent of the current collecting component and the connecting part is realized.

In some embodiments, the connecting portion is a closed structure extending circumferentially of the end cap and connected end to end. On one hand, the structure ensures that the extrusion force of the connecting part on the periphery of the current collecting component is uniform, and the deformation of the current collecting component can be effectively reduced; on the other hand, the flow area of the current collecting member and the end cover is increased.

In some embodiments, the end cap further includes a body portion connected to the case, the body portion having, in a thickness direction, an inner surface facing the current collecting member and an outer surface opposite to each other, and a recess portion provided at the inner surface to protrude the connecting portion; the concave portion is provided at a position of the body portion corresponding to the connection portion, and the concave portion is recessed from the outer surface in a direction close to the current collecting member. The arrangement of the concave part reduces the thickness of the end cover at the position of the connecting part, the connecting part and the current collecting component are connected together more easily, and the stability of the connecting part and the current collecting component after connection is enhanced.

In some embodiments, the body portion comprises a pressure relief portion, the connecting portion being arranged around the pressure relief portion, the pressure relief portion being provided with the indenting groove. The end cover has a pressure relief function, and the weak area is formed at the position of the score groove arranged on the pressure relief part so as to crack when the pressure or temperature inside the battery monomer reaches a threshold value, so that the pressure inside the battery monomer is relieved.

In some embodiments, the pressure relief part partially protrudes towards the direction close to the current collecting component and forms a boss, and a groove is formed at the position, corresponding to the boss, of one side of the pressure relief part, which is far away from the current collecting component; the surface of the lug boss facing the current collecting member is provided with a mark carving groove; and/or the groove has a second groove bottom surface provided with an engraving groove. This kind of structure makes the end cover set up the regional whole sunken to battery monomer inside of carving the mark groove, and when the end cover received the impact force from battery monomer outside, the impact force was difficult for directly using the region that the end cover set up the recess to reach the regional purpose of protection end cover setting carving the mark groove, reduce the end cover and lead to setting up the regional risk that destroys the fracture of carving the mark groove because of receiving the impact force.

In some embodiments, the bosses are spaced apart from the current collecting member in the thickness direction. So that a certain gap exists between the lug boss and the current collecting component, the current collecting component is not easy to influence the pressure relief of the end cover, and the end cover can be ensured to normally relieve the pressure when the internal pressure or temperature of the single battery reaches a threshold value.

In a second aspect, an embodiment of the present application provides a battery, which includes a box and a single battery provided in any one of the embodiments of the first aspect, where the single battery is accommodated in the box.

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

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 in accordance with some embodiments of the present application;

fig. 3 is a cross-sectional view of a battery cell provided in some embodiments of the present application;

fig. 4 is a partial view of the battery cell shown in fig. 3;

fig. 5 is a schematic structural view of the current collecting member shown in fig. 4;

fig. 6 is a cross-sectional view of the current collecting member shown in fig. 5;

fig. 7 is a partially enlarged view of the battery cell shown in fig. 4 at a;

fig. 8 is a schematic structural view of a current collecting member according to further embodiments of the present application;

fig. 9 is a schematic view of the connection of the end cap to the current collecting member shown in fig. 4.

Icon: 10-a box body; 11-a first part; 12-a second part; 20-a battery cell; 21-a housing; 22-an electrode assembly; 221-pole ear; 23-end caps; 231-a connecting portion; 232-body portion; 2321-inner surface; 2322-outer surface; 2323-relief; 2324-notching groove; 2325-boss; 2326-groove; 2326a — second groove bottom face; 233-a recess; 24-a current collecting member; 241-accommodating grooves; 2411-a first groove bottom surface; 2412-a first groove side; 2413-a second groove side; 242-a first surface; 243-a second surface; 244-first connection region; 245-a second attachment zone; 246-a central hole; 25-an electrode terminal; 100-a battery; 200-a controller; 300-a motor; 1000-a vehicle; z-thickness direction; x-a first direction.

Detailed Description

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

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

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

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

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

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

The appearances of "a plurality" in this application are intended to mean more than two (including two).

In the present application, the battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited in the embodiments of the present application. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells are generally divided into three types in an encapsulation manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are also not limited in the embodiment of the application.

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

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

In the battery cell, the electrode assembly and the end cap may be electrically connected by a current collecting member to output battery cell power through the end cap or a case connected to the end cap. Wherein the current collecting member is connected to the electrode assembly, and the connection part of the end cap is connected to the current collecting member.

In order to reduce the play of the electrode assembly in the case, a pressing force may be applied to the current collecting member through the connection portion of the end cap, and the electrode assembly and the current collecting member may be confined in the case after the end cap is connected to the case. The inventors have noted that, with the battery cell of this structure, it is easy for the electrical connection between the end cap and the electrode assembly to fail.

The inventor researches and discovers that when a single battery is assembled, after an end cover is connected with a shell, a connecting part of the end cover generates large extrusion force on a current collecting component, so that the current collecting component is greatly deformed, the connection between the current collecting component and an electrode assembly fails, the condition that the electrical connection between the end cover and the electrode assembly fails occurs, and the stability of the electrical connection between the end cover and the electrode assembly is poor.

In view of this, the present embodiments provide a battery cell that accommodates at least a portion of a connection portion of an end cover by providing an accommodation groove on a surface of a current collecting member facing the end cover. The holding tank can provide the space of dodging for connecting portion, and the end cover can form stress buffer zone in the position that sets up the holding tank to reduce connecting portion and be connected the back at end cover and casing and to the extrusion force of collecting flow component, reduce the deflection of collecting flow component, reduce the collection flow component and receive the extrusion force of connecting portion and the deflection is too big, cause the risk that collecting flow component and electrode subassembly are connected and are failed, improved the stability that end cover and electrode subassembly are connected electrically.

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. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like; spacecraft include aircraft, rockets, space shuttles, and spacecraft, among others; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not specifically limit the above-mentioned electric devices.

For convenience of explanation, the following embodiments will be described by taking an electric device as an example of a vehicle.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present disclosure. 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 case 10 is used to accommodate the battery cell 20.

The case 10 is a component for accommodating the battery cell 20, the case 10 provides an accommodating space for the battery cell 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, and the first portion 11 and the second portion 12 cover each other to define a receiving space for receiving the battery cell 20. The first and

second portions

11 and 12 may be in various shapes, such as rectangular parallelepiped, cylindrical, etc. The first portion 11 may be a hollow structure with one side open, the second portion 12 may also be a hollow structure with one side open, and the open side of the second portion 12 is covered on the open side of the first portion 11, thereby forming the box body 10 with a receiving space. The first portion 11 may have a hollow structure with one side opened, the second portion 12 may have a plate-like structure, and the second portion 12 may cover the opened side of the first portion 11 to form the case 10 having the receiving space. The first part 11 and the second part 12 may be sealed by a sealing element, which may be a sealing ring, a sealant or the like.

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

In some embodiments, the battery 100 may further include a bus member, and the plurality of battery cells 20 may be electrically connected to each other through the bus member, so as to connect the plurality of battery cells 20 in series or in parallel or in series-parallel. The bus member may be a metal conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, or the like.

Referring to fig. 3, fig. 3 is a cross-sectional view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 includes a case 21, an electrode assembly 22, an end cap 23, and a current collecting member 24.

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

The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. The electrode assembly 22 may include a positive electrode tab, a negative electrode tab, and a separator. The electrode assembly 22 may have a winding type structure in which a positive electrode sheet, a separator, and a negative electrode sheet are wound, or a lamination type structure in which a positive electrode sheet, a separator, and a negative electrode sheet are stacked. The electrode assembly 22 has a tab 221, and the tab 221 is divided into a positive tab, which may be a portion of the positive electrode sheet not coated with the positive active material layer, and a negative tab, which may be a portion of the negative electrode sheet not coated with the negative active material layer.

The end cap 23 is a member that closes the opening of the case 21 to isolate the internal environment of the battery cell 20 from the external environment. The end cap 23 defines a sealed space for accommodating the electrode assembly 22, the electrolyte, and other components together with the case 21. The shape of the end cap 23 can be adapted to the shape of the housing 21, for example, the housing 21 has a rectangular parallelepiped structure, the end cap 23 has a rectangular structure adapted to the housing 21, and for example, the housing 21 has a cylindrical structure, and the end cap 23 has a circular structure adapted to the housing 21. The end cap 23 may be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. The end cap 23 and the housing 21 may be joined together by welding.

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

The current collecting member 24 is a member that achieves electrical connection of two components, for example, the electrode assembly 22 and the end cap 23 by the current collecting member 24. The tab 221 (positive or negative) of electrode assembly 22 and end cap 23 are both connected to current collecting member 24 to electrically connect end cap 23 to electrode assembly 22.

In some embodiments, as shown in fig. 3, an electrode terminal 25 may also be provided in the battery cell 20. The case 21 has a hollow structure with an opening formed at one end, the end cap 23 is connected to the case 21 and closes the opening of the case 21, the electrode terminal 25 may be disposed at one end of the case 21 opposite to the end cap 23, the electrode terminal 25 is electrically connected to one tab 221 of the electrode assembly 22, and the end cap 23 is electrically connected to the other tab 221 of the electrode assembly 22 through the current collecting member 24.

Illustratively, the electrode terminal 25 is riveted to an end of the housing 21 opposite the end cap 23. The tab 221 of the electrode assembly 22 electrically connected to the electrode terminal 25 is a positive tab, and the tab 221 of the electrode assembly 22 electrically connected to the end cap 23 is a negative tab.

Referring to fig. 4, fig. 4 is a partial view of the battery cell 20 shown in fig. 3. The embodiment of the application provides a battery cell 20, and the battery cell 20 comprises a shell 21, an electrode assembly 22, an end cover 23 and a current collecting component 24. The housing 21 has an opening. Electrode assembly 22 is housed in case 21. The end cap 23 is attached to the housing 21 and closes the opening. A current collecting member 24 is located in the case 21, the current collecting member 24 is disposed on a side of the electrode assembly 22 facing the end cap 23, and the current collecting member 24 connects the end cap 23 and the electrode assembly 22. The end cap 23 includes a connecting portion 231 connected to the current collecting member 24, and a receiving groove 241 is provided on a surface of the current collecting member 24 facing the end cap 23 along the thickness direction Z of the end cap 23, and the connecting portion 231 is at least partially received in the receiving groove 241.

The current collecting member 24 is a part that realizes electrical connection of the end cap 23 and the electrode assembly 22. The current collecting member 24 may be various shapes, such as a circle, a rectangle, etc. The shape of the current collecting member 24 may be adapted to the shape of the case 21. For example, the housing 21 is a cylinder, the current collecting member 24 is a circular structure, and the current collecting member 24 may also be referred to as a current collecting plate. The current collecting member 24 is connected to both the electrode assembly 22 and the end cap 23. The current collecting member 24 is coupled to the tabs 221 of the electrode assembly 22, and the current collecting member 24 is coupled to the connection portion 231 of the end cap 23. The connection of the current collecting member 24 and the tabs 221 of the electrode assembly 22 may be such that they are in contact only, and they are not fixed, for example, the current collecting member 24 and the tabs 221 of the electrode assembly 22 abut against each other; the current collecting member 24 and the tabs 221 of the electrode assembly 22 may be connected by fixing them to each other, for example, by welding the current collecting member 24 and the tabs 221 of the electrode assembly 22. The connection of the connection portion 231 and the current collecting member 24 may be such that both are in contact only, and both are not fixed, such as the connection portion 231 and the current collecting member 24 abut against each other; the connection portion 231 and the current collecting member 24 may be connected by fixing them to each other, for example, by welding the connection portion 231 and the current collecting member 24. The tab 221 of the electrode assembly 22 connected to the current collecting member 24 may be a positive tab or a negative tab.

The connection portion 231 is a portion where the end cap 23 is connected to the current collecting member 24. The connection portion 231 may be a protrusion of the end cap 23 partially protruding toward the inside of the battery cell 20, and the protrusion and the end cap 23 contact each other to achieve an excess flow between the end cap 23 and the current collecting member 24.

The receiving groove 241 forms a concave space to receive the connection part 231. The receiving groove 241 may receive the entire connecting portion 231, or may receive a part of the connecting portion 231. The receiving groove 241 is disposed on a surface of the current collecting member 24 facing the end cover 23, the surface of the current collecting member 24 facing the end cover 23 is a first surface 242, a surface of the current collecting member 24 facing away from the end cover 23 is a second surface 243, and the second surface 243 abuts against the tab 221 of the electrode assembly 22. The receiving groove 241 may or may not penetrate the outer circumferential surface of the current collecting member 24. The shape of the receiving groove 241 and the shape of the connecting portion 231 may be the same, for example, the receiving groove 241 and the connecting portion 231 are both annular structures; the shape of the receiving groove 241 may be different from that of the connecting portion 231, for example, the receiving groove 241 has a ring structure, and the connecting portion 231 has a semi-ring shape.

In the embodiment of the present application, the connecting portion 231 of the end cap 23 connected to the current collecting member 24 is at least partially accommodated in the accommodating groove 241, the accommodating groove 241 can provide an avoiding space for the connecting portion 231, and the end cap 23 can form a stress buffering area at the position where the accommodating groove 241 is disposed, so that the pressing force of the connecting portion 231 to the current collecting member 24 after the end cap 23 is connected to the case 21 is reduced, the deformation amount of the current collecting member 24 is reduced, the risk that the current collecting member 24 is subjected to the pressing force of the connecting portion 231 and is deformed too much, the connection failure between the current collecting member 24 and the electrode assembly 22 is caused, and the stability of the electrical connection between the end cap 23 and the electrode assembly 22 is improved.

In some embodiments, with continued reference to fig. 4, the receiving slots 241 are closed slots extending circumferentially of the current collecting member 24 and connected end to end.

The receiving grooves 241 extend along a closed trajectory end-to-end to form closed grooves. The closed tracks may be rectangular, circular. If the closed track is circular, the accommodating groove 241 is annular, and the recessed space formed by the accommodating groove 241 is an annular space. The closed path may be adapted to the shape of the current collecting member 24, for example, the current collecting member 24 is rectangular, and the closed path is rectangular concentric with the current collecting member 24; as another example, the current collecting member 24 has a circular shape, and the closed locus has a circular shape corresponding to the current collecting member 24.

In this embodiment, the accommodating groove 241 is a closed groove that extends along the circumferential direction of the current collecting member 24 and is connected end to end, the accommodating groove 241 has better adaptability to the connecting portion 231, and the connecting portion 231 can be accommodated in the accommodating groove 241 in different directions in the circumferential direction of the end cover 23, so that the mounting difficulty of the end cover 23 is reduced.

In some embodiments, referring to fig. 5, fig. 5 is a schematic structural view of the current collecting member 24 shown in fig. 4, and the accommodating groove 241 is an annular groove.

Illustratively, the current collecting member 24 has a circular shape, and the receiving groove 241 is concentrically disposed with the current collecting member 24.

In fig. 5, the receiving groove 241 does not penetrate the outer circumferential surface of the current collecting member 24, and the receiving groove 241 has an outer side surface and an inner side surface. In other embodiments, the receiving groove 241 may also penetrate the outer circumferential surface of the current collecting member 24, such that the receiving groove 241 has only an inner side surface, but not an outer side surface.

In this embodiment, the annular receiving groove 241 has a simple structure and is easy to mold.

In some embodiments, referring to fig. 6, fig. 6 is a cross-sectional view of the current collecting member 24 shown in fig. 5, the receiving groove 241 has a first groove bottom surface 2411 and a first groove side surface 2412, and the first groove side surface 2412 is connected to the first groove bottom surface 2411. The first groove bottom face 2411 faces the connection portion 231 (not shown in fig. 6) in the thickness direction Z of the end cover 23. The first groove side surface 2412 is located inside the connection portion 231 in the first direction X perpendicular to the thickness direction Z of the end cap 23. Wherein an angle between the first groove side surface 2412 and the first groove bottom surface 2411 is θ ₁ And satisfies the following conditions: theta is less than 90 DEG ₁ < 180 deg. It will be appreciated that the first channel side 2412 is disposed at an obtuse angle to the first channel bottom 2411.

In embodiments where the current collecting members 24 are circular, the first direction X is radial to the current collecting members 24. In embodiments where the current collecting member 24 is rectangular, the first direction X may be a length direction of the current collecting member 24 or a width direction of the current collecting member 24. The first groove side surface 2412 is located inside the connecting portion 231 in the first direction X, and the first groove side surface 2412 is an inner side surface of the accommodating groove 241.

The first groove bottom surface 2411 is a surface of the receiving groove 241 located at the deepest position in the depth direction, and the first groove bottom surface 2411 may be perpendicular to the thickness direction Z of the end cover 23. The first groove side 2412 may be a slanted plane or a tapered plane. It will be appreciated that in embodiments where the receiving groove 241 is an annular groove, the first groove side surface 2412 is a conical surface.

In this embodiment, the first groove side surface 2412 located inside the connecting portion 231 is disposed at an obtuse angle with the first groove bottom surface 2411, the first groove side surface 2412 is in an inclined state, and the first groove side surface 2412 guides the connecting portion 231, so that the connecting portion 231 can enter the accommodating groove 241 more easily.

In some embodiments, referring to fig. 6, the receiving groove 241 further includes a second groove side 2413, the second groove side 2413 is connected to the first groove bottom 2411, and the first groove side 2412 is located outside the connecting portion 231 along the first direction X; wherein an angle between the second groove side surface 2413 and the first groove bottom surface 2411 is θ ₂ And satisfies the following conditions: theta is less than 90 DEG ₂ < 180 deg. Understandably, the second channel side 2413 is disposed at an obtuse angle to the first channel bottom 2411.

The second groove side surface 2413 is located outside the connection portion 231 in the first direction X, and the second groove side surface 2413 is an outer side surface of the accommodating groove 241. The second groove side 2413 may be a slanted plane or a tapered plane. It can be understood that in the embodiment where the receiving groove 241 is an annular groove, the second groove side surface 2413 is a conical surface, and the space between the second groove side surface 2413 and the first groove side surface 2412 is a recessed space of the receiving groove 241.

In this embodiment, the second groove side surface 2413 located outside the connecting portion 231 is disposed at an obtuse angle with the first groove side surface 2411, the second groove side surface 2413 is in an inclined state, and the second groove side surface 2413 guides the connecting portion 231, so that the connecting portion 231 can enter the accommodating groove 241 more easily.

In some embodiments, please refer to fig. 7, which is a partial enlarged view of a portion a of the battery cell 20 shown in fig. 4. In the first direction X, the first groove side surface 2412 and the second groove side surface 2413 are both disposed at a gap from the connection portion 231.

It will be appreciated that the connecting portion 231 is not in contact with either the first or

second slot side

2412, 2413. The connection portion 231 abuts against the first groove bottom surface 2411 of the receiving groove 241 to achieve electrical connection between the connection portion 231 and the current collecting member 24.

Taking the receiving groove 241 and the connecting portion 231 as an example, both of which are annular structures, the first direction X is a radial direction of the current collecting member 24, and the first groove side surface 2412 of the receiving groove 241 is spaced from the inner side surface of the connecting portion 231, and the second groove side surface 2413 of the receiving groove 241 is spaced from the outer side surface of the connecting portion 231 along the first direction X.

In the present embodiment, the first and second

groove side surfaces

2412 and 2413 are spaced from the connection portion 231 in the first direction X, so that the gap between the first and second

groove side surfaces

2412 and 2413 is larger than the width of the portion of the connection portion 231 located in the accommodation groove 241, on one hand, so that the connection portion 231 is more easily inserted into the accommodation groove 241, and on the other hand, the risk that the connection portion 231 applies a pressing force to the first and second

groove side surfaces

2412 and 2413 to increase the deformation amount of the current collecting member 24 is reduced.

In other embodiments, the inner side surface and the outer side surface of the connecting portion 231 may respectively abut against the first groove side surface 2412 and the second groove side surface 2413 of the receiving groove 241, and the connecting portion 231 is supported by the inclined first groove side surface 2412 and the inclined second groove side surface 2413, so that the connecting portion 231 and the first groove bottom surface 2411 of the receiving groove 241 are spaced apart from each other.

In some embodiments, please refer to fig. 8, fig. 8 is a schematic structural diagram of a current collecting member 24 according to other embodiments of the present disclosure. The receiving groove 241 has a first groove bottom surface 2411 and a second groove side surface 2413, and the second groove side surface 2413 is connected to the first groove bottom surface 2411. The first groove bottom face 2411 faces the connection portion 231 (not shown in fig. 8) in the thickness direction Z of the end cover 23. The second groove side 2413 is located outside the connection portion 231 in the first direction X, which is perpendicular to the thickness direction Z of the end cap 23. Wherein an angle between the second groove side surface 2413 and the first groove bottom surface 2411 is θ ₂ And satisfies the following conditions: theta < 90 DEG ₂ < 180 deg. Understandably, the second channel side 2413 is disposed at an obtuse angle to the first channel bottom 2411.

The first groove bottom surface 2411 is a surface of the receiving groove 241 located at the deepest position in the depth direction, and the first groove bottom surface 2411 may be perpendicular to the thickness direction Z of the end cover 23. The second groove side surface 2413 is an outer side surface of the receiving groove 241. The second groove side 2413 may be a slanted plane or a tapered plane.

Illustratively, as shown in fig. 8, the receiving groove 241 is circular, the second groove side surface 2413 is a conical surface, and a space defined by the second groove side surface 2413 is a concave space of the receiving groove 241.

In some embodiments, with reference to fig. 6 and fig. 7, the receiving groove 241 includes a first groove side surface 2412 and a second groove side surface 2413, and the first groove side surface 2412 and the second groove side surface 2413 are respectively located at two sides of the connecting portion 231 along a first direction X, which is perpendicular to the thickness direction Z of the end cap 23. The distance between the first groove side surface 2412 and the second groove side surface 2413 in the first direction X gradually decreases along the depth direction of the receiving groove 241.

In the thickness direction Z of the end cover 23, the current collecting member 24 has a first surface 242 and a second surface 243 which are opposite, the first surface 242 faces the end cover 23, the second surface 243 faces away from the end cover 23, the receiving groove 241 is recessed from the first surface 242 in a direction close to the second surface 243, the receiving groove 241 forms an opening in the first surface 242, and the direction in which the first surface 242 faces the second surface 243 is the depth direction of the receiving groove 241.

In the embodiment where the receiving groove 241 has an annular structure, the distance between the first groove side surface 2412 and the second groove side surface 2413 in the first direction X is the difference between the radii of the first groove side surface 2412 and the second groove side surface 2413. Of course, the distance between the first groove side surface 2412 and the second groove side surface 2413 in the first direction X may gradually decrease along the depth direction of the accommodating groove 241 in various ways, for example, the first groove side surface 2412 and the second groove side surface 2413 are both disposed at an obtuse angle with respect to the first groove bottom surface 2411, and for example, one of the first groove side surface 2412 and the second groove side surface 2413 is disposed at an obtuse angle with respect to the first groove bottom surface 2411, and the other is disposed at a right angle with respect to the first groove bottom surface 2411.

In the present embodiment, the width of the receiving groove 241 is gradually narrowed from the opening position thereof in the depth direction, so that the connecting portion 231 more easily enters into the receiving groove 241.

In some embodiments, with continued reference to fig. 6 and 7, the current collecting member 24 includes a first connection region 244 and a second connection region 245. The first connection region 244 is connected to the connection portion 231, and the first connection region 244 is formed at a position where the receiving groove 241 is disposed on the current collecting member 24. The second connection region 245 is connected to the electrode assembly 22. Wherein projections of the first connecting region 244 and the second connecting region 245 on a plane perpendicular to the thickness direction Z of the end cap 23 do not overlap.

The first connection region 244 is a portion where the current collecting member 24 is connected to the connection portion 231, after the current collecting member 24 is provided with the receiving groove 241, a remaining portion of the current collecting member 24 corresponding to the position of the receiving groove 241 is the first connection region 244, in other words, the thickness direction Z of the end cover 23, and a portion of the current collecting member 24 located between the first groove bottom surface 2411 and the second surface 243 of the receiving groove 241 is the first connection region 244. Taking the first connection region 244 welded to the connection portion 231 as an example, a welding mark formed by welding the first connection region 244 to the connection portion 231 is located at the first connection region 244.

The second connection region 245 is a portion where the current collecting member 24 is connected to the electrode assembly 22. Taking the example where the second connection region 245 is welded to the tab 221 of the electrode assembly 22, a weld formed by welding the second connection region 245 to the tab 221 is located at the second connection region 245. It will be appreciated that the projections of the weld formed by welding the first connection region 244 to the connection portion 231 and the weld formed by welding the second connection region 245 to the tab 221 onto a plane perpendicular to the thickness direction Z of the end cap 23 do not overlap.

In the embodiment, the first connection region 244 and the second connection region 245 are disposed in a staggered manner, the first connection region 244 and the second connection region 245 are not affected by each other, and the connection between the first connection region 244 and the connection portion 231 does not affect the connection between the second connection region 245 and the electrode assembly 22, so that the connection stability between the current collecting member 24 and the electrode assembly 22 is improved. For example, after the second connection region 245 is welded to the tab 221 of the electrode assembly 22, and when the connection portion 231 and the first connection region 244 are welded, because the first connection region 244 and the second connection region 245 are disposed in a staggered manner, secondary welding of the second connection region 245 can be avoided, and the influence on the connection strength between the second connection region 245 and the tab 221 of the electrode assembly 22 is reduced.

In some embodiments, with continued reference to fig. 6 and 7, the first connection region 244 is disposed around the outside of the second connection region 245.

In the present embodiment, the first connecting region 244 has a ring-shaped structure, and the receiving groove 241 correspondingly has a ring-shaped structure. The portion of the current collecting member 24 located inboard of the first connection region 244 is a second connection region 245.

In the present embodiment, the first connection region 244 is arranged around the outside of the second connection region 245, so that the first connection region 244 has a larger size, enabling an increase in the flow area of the current collecting member 24 and the end cap 23.

It should be noted that in other embodiments, the second connection region 245 may be disposed around the outside of the first connection region 244.

In some embodiments, with reference to fig. 6, the thickness of the second connecting region 245 is L, and the depth of the accommodating groove 241 is H, so as to satisfy: H/L is more than or equal to 0.15 and less than 1.

The thickness of the second connection region 245 is the thickness of the current collecting member 24. In fig. 6, the thickness of the second connection region 245 is the distance between the first surface 242 and the second surface 243 in the thickness direction Z of the end cap 23, and the depth of the receiving groove 241 is the distance between the first surface 242 and the first groove bottom 2411 in the thickness direction Z of the end cap 23.

Illustratively, 0.1mm ≦ H ≦ 1 mm.

In the present embodiment, the ratio of the depth of the receiving groove 241 to the thickness of the second connection region 245 is set within a reasonable range so that the depth of the receiving groove 241 is not excessively small to receive more portions of the connection portion 231, reducing the amount of deformation of the current collecting member 24.

In some embodiments, referring to fig. 7, the connecting portion 231 abuts against the first groove bottom surface 2411 of the accommodating groove 241 along the thickness direction Z of the end cap 23.

When the connection portion 231 abuts against the first groove bottom surface 2411 of the housing groove 241, both the first groove side surface 2412 and the second groove side surface 2413 of the housing groove 241 may be in contact with the connection portion 231, or may be provided with a gap. For example, in fig. 7, the first groove side 2412 and the second groove side 2413 of the receiving groove 241 are both arranged with a gap in the connection portion 231.

In the present embodiment, the connection portion 231 abuts against the first groove bottom surface 2411 of the accommodation groove 241 in the thickness direction Z of the end cover 23, increasing the contact area of the connection portion 231 with the current collecting member 24, and thus increasing the flow area of the current collecting member 24 with the end cover 23.

In some embodiments, the current collecting member 24 is welded with the connection portion 231. The current collecting member 24 and the connection portion 231 are firmly connected, and stable overcurrent of the current collecting member 24 and the connection portion 231 is realized.

In embodiments where the current collecting member 24 abuts against the first groove bottom surface 2411 of the receiving groove 241, the connection portion 231 may be welded and fixed with the first connection region 244 of the current collecting member 24 by means of penetration welding.

In some embodiments, the connection portion 231 is a closed structure extending along the circumference of the end cap 23 and connected end to end.

Illustratively, the connecting portion 231 is of an annular configuration, and the receiving groove 241 is also of an annular configuration.

In the present embodiment, the connection portion 231 is a closed end-to-end structure, which, on one hand, makes the extrusion force of the connection portion 231 on the periphery of the current collecting member 24 uniform, and can effectively reduce the deformation of the current collecting member 24; on the other hand, the flow area of the current collecting member 24 and the end cap 23 is increased.

In some embodiments, referring to fig. 9, fig. 9 is a schematic view illustrating the connection between the end cap 23 and the current collecting member 24 shown in fig. 4. The end cap 23 further includes a body portion 232 and a recess portion 233, the body portion 232 is connected to the housing 21, the body portion 232 has an inner surface 2321 and an outer surface 2322 opposite to each other in the thickness direction Z of the end cap 23, the inner surface 2321 faces the current collecting member 24, and the connecting portion 231 is protruded from the inner surface 2321. The concave portion 233 is provided at a position of the body portion 232 corresponding to the connection portion 231, and the concave portion 233 is recessed from the outer surface 2322 in a direction toward the current collecting member 24.

The body 232 and the housing 21 may be fixed by welding. The body portion 232 may be circular, rectangular, etc. Taking the main body 232 as an example, a portion of the main body 232 beyond the outer surface of the connecting portion 231 may be welded to the housing 21 along the radial direction of the main body 232.

The shape of the concave portion 233 is the same as that of the connection portion 231. Illustratively, the concave portion 233 and the connecting portion 231 are both annular structures, and the concave portion 233 and the connecting portion 231 are both disposed coaxially with the body portion 232.

In the present embodiment, the provision of the recessed portion 233 reduces the thickness of the end cap 23 at the position of the connection portion 231, makes it easier to connect the connection portion 231 and the current collecting member 24 together, and enhances the stability after the connection of the connection portion 231 and the current collecting member 24. For example, when the connection portion 231 is welded to the current collecting member 24, the thickness of the end cover 23 at the position of the connection portion 231 is reduced, so that the connection portion 231 is more firmly welded to the current collecting member 24.

In some embodiments, with continued reference to fig. 9, the main body 232 includes a pressure relief portion 2323, the connecting portion 231 surrounds the pressure relief portion 2323, and the pressure relief portion 2323 is provided with a scored groove 2324.

The portion of the body 232 located inside the inner surface of the connecting portion 231 is a pressure relief portion 2323. Taking the connection portion 231 as an annular structure as an example, the pressure relief portion 2323 has a circular structure located inside the inner side surface of the connection portion 231. The indentation 2324 on the pressure relief 2323 may be of various shapes, such as circular, U-shaped, linear, etc.

The pressure relief portion 2323 is provided with the notch 2324 at a position to form a weak region to be ruptured when the pressure or temperature inside the battery cell 20 reaches a threshold value, so as to relieve the pressure inside the battery cell 20. The end cover 23 with the structure has a pressure relief function, and the safety of the battery cell 20 is improved.

In some embodiments, with continued reference to fig. 9, the pressure relief portion 2323 partially protrudes toward the current collecting member 24 and forms a boss 2325, and a groove 2326 is formed at a position corresponding to the boss 2325 on a side of the pressure relief portion 2323 facing away from the current collecting member 24. The surface of the boss 2325 facing the current collecting member 24 is provided with a scored groove 2324; and/or, the groove 2326 has a second groove bottom surface 2326a, the second groove bottom surface 2326a being provided with the score groove 2324.

The bosses 2325 on the pressure relief part 2323 can be formed by stamping, after stamping the side of the pressure relief part 2323 away from the current collecting member 24, the side of the pressure relief part 2323 away from the current collecting member 24 is formed into the grooves 2326, and the side of the pressure relief part 2323 facing the current collecting member 24 is correspondingly formed into the bosses 2325.

Illustratively, the boss 2325 and the groove 2326 are both circular, the boss 2325 is disposed coaxially with the groove 2326, and the diameter of the boss 2325 is greater than the diameter of the groove 2326.

The second groove bottom surface 2326a is a surface of the groove 2326 located at the deepest position in the depth direction, and a direction in which the outer surface 2322 of the body portion 232 points to the inner surface 2321 is the depth direction of the groove 2326. Illustratively, the second slot bottom surface 2326a is located between the outer surface 2322 and the inner surface 2321 of the body portion 232 along the thickness direction Z of the end cap 23.

For example, in fig. 9, score groove 2324 is provided on the surface of boss 2325 facing current collecting member 24, i.e., score groove 2324 is recessed from the surface of boss 2325 facing current collecting member 24 in the direction of second groove bottom surface 2326 a.

In this embodiment, the whole area of the end cover 23 where the scored groove 2324 is provided is recessed towards the inside of the battery cell 20, and when the end cover 23 receives an impact force from the outside of the battery cell 20, the impact force is not easily directly applied to the area of the end cover 23 where the groove 2326 is provided, so that the purpose of protecting the area of the end cover 23 where the scored groove 2324 is provided is achieved, and the risk that the area where the scored groove 2324 is provided is damaged and cracked due to the impact force applied to the end cover 23 is reduced.

In some embodiments, with continued reference to fig. 9, the bosses 2325 are spaced apart from the current collecting member 24 in the thickness direction Z of the end cover 23.

It will be appreciated that a gap is formed between the surface of the boss 2325 facing the current collecting member 24 and the first surface 242 of the current collecting member 24.

Illustratively, the current collecting member 24 is provided with a central aperture 246, and the gap between the boss 2325 and the current collecting member 24 communicates with the central aperture 246.

In this embodiment, a certain gap exists between the boss 2325 and the current collecting member 24, and the current collecting member 24 is not easy to affect the pressure relief of the end cap 23, so as to ensure that the end cap 23 can normally relieve the pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value.

The embodiment of the application provides a battery 100, which comprises a box body 10 and a battery unit 20 provided by any one of the above embodiments, wherein the battery unit 20 is accommodated in the box body 10.

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

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

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

Claims

1. A battery cell, comprising:

a housing having an opening;

an electrode assembly housed within the case;

an end cap connected to the housing and closing the opening;

a current collecting member positioned within the case and disposed at a side of the electrode assembly facing the end cap, the current collecting member connecting the end cap and the electrode assembly;

the end cover comprises a connecting part connected with the current collecting component, a containing groove is formed in the surface, facing the end cover, of the current collecting component along the thickness direction of the end cover, and the connecting part is at least partially contained in the containing groove.

2. The battery cell as recited in claim 1 wherein the receiving groove is a closed groove extending circumferentially of the current collecting member and joined end to end.

3. The battery cell as recited in claim 2 wherein the receiving groove is an annular groove.

4. The battery cell as recited in claim 1, wherein the receiving groove has a first groove bottom surface and a first groove side surface, the first groove side surface being continuous with the first groove bottom surface;

the first groove bottom face faces the connection portion in the thickness direction;

the first groove side surface is located on the inner side of the connecting portion along a first direction, and the first direction is perpendicular to the thickness direction;

wherein an angle between the first groove side surface and the first groove bottom surface is θ ₁ And satisfies the following conditions: theta is less than 90 DEG ₁ ＜180°。

5. The battery cell as recited in claim 4 wherein the receiving groove further comprises a second groove side surface that is continuous with the first groove bottom surface, the first groove side surface being located outside of the connecting portion in the first direction;

wherein an angle between the second groove side surface and the first groove bottom surface is θ ₂ And satisfies the following conditions: theta is less than 90 DEG ₂ ＜180°。

6. The battery cell as recited in claim 5 wherein the first and second slot sides are each spaced from the connection portion along the first direction.

7. The battery cell as recited in claim 1 wherein the receiving groove has a first groove bottom surface and a second groove side surface, the second groove side surface being continuous with the first groove bottom surface;

the second groove side surface is positioned outside the connecting part along a first direction, and the first direction is perpendicular to the thickness direction;

wherein an angle between the second groove side surface and the first groove bottom surface is θ ₂ Satisfies the following conditions: theta is less than 90 DEG ₂ ＜180°。

8. The battery cell as recited in claim 1 wherein the receiving groove includes a first groove side surface and a second groove side surface, the first and second groove side surfaces being located on either side of the connecting portion in a first direction, the first direction being perpendicular to the thickness direction;

the distance between the first groove side surface and the second groove side surface in the first direction is gradually reduced along the depth direction of the accommodating groove.

9. The battery cell according to any one of claims 1-8, wherein the current collecting member comprises:

a first connection region connected to the connection portion, the first connection region being formed at a position where the current collecting member sets the accommodation groove;

a second connection region connected to the electrode assembly;

wherein projections of the first and second connection regions on a plane perpendicular to the thickness direction do not overlap.

10. The battery cell as recited in claim 9 wherein the first connection region is disposed around the outside of the second connection region.

11. The battery cell as set forth in claim 9, wherein the second connection region has a thickness L, and the receiving groove has a depth H, such that: H/L is more than or equal to 0.15 and less than 1.

12. The battery cell as recited in any of claims 1-8, wherein the receiving groove has a first groove bottom surface against which the connecting portion abuts in the thickness direction.

13. The battery cell according to any one of claims 1 to 8, wherein the current collecting member is welded to the connection portion.

14. The battery cell according to any one of claims 1-8, wherein the connecting portion is a closed structure extending in a circumferential direction of the end cap and connected end to end.

15. The battery cell of any of claims 1-8, wherein the end cap further comprises:

a body portion connected to the case, the body portion having an inner surface and an outer surface opposite to each other in the thickness direction, the inner surface facing the current collecting member, the connecting portion being protrudingly provided on the inner surface;

and a recess portion provided at a position of the body portion corresponding to the connection portion, the recess portion being recessed from the outer surface in a direction approaching the current collecting member.

16. The battery cell as recited in claim 15 wherein the body portion includes a relief portion, the connecting portion being disposed around the relief portion, the relief portion being provided with a scored groove.

17. The battery cell as recited in claim 16, wherein the pressure relief portion partially protrudes toward the current collecting member and forms a protrusion, and a groove is formed at a position corresponding to the protrusion on a side of the pressure relief portion facing away from the current collecting member;

the surface of the lug boss facing the current collecting component is provided with the notching groove; and/or the groove has a second groove bottom surface provided with the scoring groove.

18. The battery cell as recited in claim 17 wherein the boss is disposed in a spaced relation to the current collecting member in the thickness direction.

19. A battery, comprising:

a box body;

the battery cell of any of claims 1-18, the battery cell housed within the case.

20. An electrical device comprising the battery of claim 19.