CN216529083U - End cover assembly, single battery, battery and electric equipment - Google Patents

Abstract

The application provides an end cover subassembly, battery monomer, battery and consumer, its characterized in that, including end cover, first electrode terminal, second electrode terminal, first piece that warp. The first electrode terminal and the second electrode terminal are used for inputting or outputting electric energy and are arranged on the end cover, the hardness of the first electrode terminal is smaller than that of the end cover and is insulated from the end cover, the first electrode terminal is provided with a first connecting part, and the first connecting part is positioned on one side, facing the interior of the battery cell, of the end cover in the thickness direction of the end cover. The first deformation piece is welded on the first connecting portion, the base material of the first deformation piece is the same as that of the first electrode terminal, and is arranged at intervals with the end cover in the thickness direction of the end cover, when the internal pressure of the battery monomer reaches a threshold value, the first deformation piece moves towards the direction facing the end cover, the first deformation piece is made to be in contact with the end cover, and therefore the first electrode terminal is electrically connected to the second electrode terminal through the first deformation piece and the end cover, and the risk of battery overcharge is reduced.

Description

End cover assembly, single battery, battery and electric equipment

Technical Field

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

Background

At present, a secondary battery is used as a battery, and after the secondary battery is discharged, an active material can be activated by charging to continue use. Secondary batteries are widely used in electronic devices such as mobile phones, notebook computers, battery cars, electric automobiles, and electric tools, etc.

Overcharge may occur when the secondary battery is charged, that is, after a full charge state is reached, the charging is continued, which may cause an increase in internal pressure of the battery, deformation, or leakage of liquid, so that the performance of the battery is significantly reduced and even safety problems such as explosion, ignition, etc. may be caused.

Therefore, how to reduce the risk of overcharging of the battery and improve the safety performance of the battery becomes a problem to be solved urgently.

Disclosure of Invention

The application provides an end cover subassembly, battery monomer, battery and consumer for reduce the risk that the battery overcharged, improve the security performance of battery.

In a first aspect, an end cap assembly for a battery cell includes an end cap, a first electrode terminal, a second electrode terminal, and a first deformation element. The first electrode terminal and the second electrode terminal are used for inputting or outputting electric energy and are arranged on the end cover, the hardness of the first electrode terminal is smaller than that of the end cover and is insulated from the end cover, the first electrode terminal is provided with a first connecting portion, and the first connecting portion is located on one side, facing the interior of the battery cell, of the end cover in the thickness direction of the end cover. The first deformation piece is welded on the first connecting portion, the base material of the first deformation piece is the same as that of the first electrode terminal, and is arranged at intervals with the end cover in the thickness direction of the end cover, when the internal pressure of the battery cell reaches a threshold value, the first deformation piece moves towards the direction facing the end cover, so that the first deformation piece is in contact with the end cover, and the first electrode terminal is electrically connected to the second electrode terminal through the first deformation piece and the end cover.

According to the embodiment of the application, the hardness of the end cover is greater than that of the first electrode terminal, so that the pressure resistance of the battery cell is enhanced. The base material of the first deformation piece is the same as that of the first electrode terminal, so that the first deformation piece can be welded with the first connecting part and electrically connected. The first deformation piece is arranged at an interval with the end cover in the thickness direction of the end cover, so that the first deformation piece and the end cover are insulated. When the internal pressure of the battery cell reaches a threshold value, the first deformation piece acts towards the direction facing the end cover, and the first deformation piece is contacted with the end cover, so that the first electrode terminal is electrically connected with the second electrode terminal through the end cover to form a protection loop, and an electrode assembly in the battery cell is short-circuited, thereby reducing the risk of overcharge of the battery and improving the safety performance of the battery.

In some embodiments, the second electrode terminal is electrically connected to the end cap.

According to this application embodiment, second electrode terminal is connected with the end cover electricity, and when battery monomer internal pressure reached the threshold value, first deformation piece moved towards the direction towards the end cover for first deformation piece and end cover contact, first electrode terminal passes through first deformation piece and end cover electricity and connects in second electrode terminal, thereby with the battery internal component short circuit, reduces the risk that the battery overcharged, and simple structure.

In some embodiments, the second electrode terminal has a hardness less than that of the end cap and is insulated from the end cap, the second electrode terminal has a second connecting portion, the second connecting portion is located on a side of the end cap facing the inside of the battery cell in a thickness direction of the end cap, the second connecting portion is used for welding and disposing a second deformation member, and a base material of the second deformation member is the same as a base material of the second electrode terminal and is spaced from the end cap in the thickness direction; when the internal pressure of the battery cell reaches a threshold value, the second deformation piece moves towards the direction facing the end cover, so that the second deformation piece is contacted with the end cover, and the first electrode terminal is electrically connected to the second electrode terminal through the first deformation piece, the end cover and the second deformation piece.

According to this application embodiment, second electrode terminal and end cover are insulating, and have the second connecting portion to welding second deformation piece, second deformation piece and end cover interval set up, when free internal pressure of battery reaches the threshold value, first deformation piece and second deformation piece all move towards the direction towards the end cover for first electrode terminal and second electrode terminal pass through the end cover and realize the electricity and connect, constitute protection return circuit, with the short circuit electrode subassembly in the battery monomer, reduced the risk that the battery overcharged.

In some embodiments, the first connecting portion is provided with a first welding hole corresponding to the shape of the first deformation piece, and when the first deformation piece moves towards the direction facing the end cover, the first deformation piece at least partially penetrates through the first welding hole and is electrically connected with the end cover. And when the second deformation piece moves towards the direction facing the end cover, at least part of the second deformation piece passes through the second welding hole and is electrically connected with the end cover.

According to this application embodiment, be equipped with on the first connecting portion with the first welding hole that warp the piece shape and correspond, be equipped with on the second connecting portion with the second welding hole that warp the piece shape and correspond for first warp piece and second warp piece can weld with first connecting portion and second connecting portion respectively, and have the space of action, so that when battery monomer internal pressure reached the threshold value, first warp piece and second warp piece can partly pass first welding hole and second welding hole, and contact and the electricity is connected with the end cover.

In some embodiments, the first welding hole and the second welding hole each include a first-stage hole and a second-stage hole that are coaxially disposed, the second-stage hole is closer to the end cap than the first-stage hole, a diameter of the second-stage hole is smaller than a diameter of the first-stage hole, a step surface is formed between a hole wall of the first-stage hole and a hole wall of the second-stage hole, the first deformation member is welded on the step surface of the first welding hole, and the second deformation member is welded on the step surface of the second welding hole.

According to the embodiment of the application, the first welding hole and the second welding hole are stepped holes, so that stepped surfaces are formed on the first welding hole and the second welding hole, the first deformation piece and the second deformation piece are welded on the stepped surfaces, the side wall of the first-stage hole is limited, the first deformation piece and the first connecting portion are connected more accurately and reliably, the second deformation piece and the second connecting portion are connected more accurately and reliably, at least part of the first connecting portion and at least part of the second connecting portion are accommodated in the first-stage hole, and the energy density of the battery is improved.

In some embodiments, the first deformation piece and the second deformation piece are both turning pieces, and each turning piece comprises a welding part, a boss and a connecting part located between the welding part and the boss. The welding part is located the edge of upset piece, and the boss is located the central zone of upset piece, and connecting portion are used for connecting welding part and boss, and when battery monomer inside reached the threshold value, the upset piece moved towards the direction towards the end cover for the boss contacts with the end cover.

According to this application embodiment, the upset piece provides the welding part, is convenient for it and first connecting portion or second connecting portion welding, and connecting portion warp when battery monomer internal pressure reaches the threshold value for first deformation piece or second deformation piece can move towards the end cover, realize the electricity with the end cover and be connected, and the boss has increased the area of contact of upset piece with the end cover, thereby has increased the electric current area of overflowing when electrically connecting, has reduced the generating heat of contact department.

In some embodiments, the hardness of the base material of the first deforming member is greater than the hardness of the base material of the second deforming member, and the area of the first deforming member is greater than the area of the second deforming member.

According to this application embodiment, the area of first deformation piece is greater than the area of second deformation piece, when battery monomer internal pressure reached the threshold value, has improved the possibility that first deformation piece and second deformation piece can move towards the end cover simultaneously for the subassembly of battery monomer inside can be more in time by the short circuit, thereby has further improved the security performance of battery.

In some embodiments, the hardness of the base material of the first deformation piece is greater than that of the base material of the second deformation piece, and the minimum thickness of the connecting part of the first deformation piece is smaller than that of the connecting part of the second deformation piece.

According to this application embodiment, the connecting portion of first deformation spare is littleer than the connecting portion thickness in the second deformation spare, has improved first deformation spare and second deformation spare when battery monomer internal pressure reaches the threshold value, can move towards the possibility of end cover action simultaneously for the subassembly of battery monomer inside can be more in time by the short circuit, thereby has further improved the security performance of battery.

In some embodiments, the end cap assembly comprises a first sealing element and a second sealing element, the first sealing element is arranged between the first deformation element and the end cap in the thickness direction to form a first closed space, and the second sealing element is arranged between the second deformation element and the end cap to form a second closed space.

According to this application embodiment, through setting up first sealing member and second sealing member, form first airtight space and second airtight space, when battery monomer internal pressure reached the threshold value, the pressure that first deformation piece and second deformation piece were close to end cover one side is less than the pressure that first deformation piece and second deformation piece kept away from end cover one side to produce the pressure differential, so that first deformation piece and second deformation piece atress take place the action, realize the contact with the end cover.

In some embodiments, the end cap assembly includes a first platen insulated from the first connection; the first pressing plate comprises a first pressing part and a first fixing part, and the first pressing part is positioned on one side, away from the end cover, of the first connecting part in the thickness direction of the end cover and presses the first connecting part to enable the first sealing element to be compressed; the first fixing part is connected with the end cover so as to fix the first pressing plate on the end cover; and/or the end cap assembly comprises a second pressure plate, and the second pressure plate is insulated from the second connecting part; the second pressing plate comprises a second pressing part and a second fixing part, and the second pressing part is positioned on one side, away from the end cover, of the second connecting part in the thickness direction of the end cover and presses the second connecting part so as to compress the second sealing element; the second fixing portion is connected to the end cover to fix the second pressing plate to the end cover.

According to the embodiment of the application, the pressing part of the first pressing plate presses the first connecting part in the direction close to the end cover, and the pressing part of the second pressing plate presses the second connecting part in the direction close to the end cover, so that the first sealing part and the second sealing part are compressed, the risk of sealing failure of the first closed space and the second closed space is reduced, and the possibility of action of the first deformation part and the second deformation part when the internal pressure of the single battery reaches the threshold value is improved.

In a second aspect, embodiments of the present application provide a battery cell, which includes an electrode assembly, a case, and an end cap assembly provided in embodiments of the first aspect of the present application. The case is used for accommodating the electrode assembly, the case is provided with an opening, and the end cover is used for covering the opening.

In some embodiments, the battery cell includes a first current collecting member and a second current collecting member, and the first current collecting member and the first electrode terminal are connected at ends located inside the battery cell to electrically connect the first electrode terminal with the electrode assembly. The second current collecting member and the end of the second electrode terminal located inside the battery cell are connected such that the second electrode terminal is electrically connected with the electrode assembly.

The first current collecting member and/or the second current collecting member has a fuse portion configured to be disconnected when the first electrode terminal and the second electrode terminal are electrically connected, so that the first electrode terminal and/or the second electrode terminal are electrically disconnected from the electrode assembly.

According to the embodiment of the application, when the internal pressure of the battery cell reaches the threshold value, the first electrode terminal and the second electrode terminal are electrically connected through the end cover, at the moment, the current passing through the first current collecting member and the second current collecting member is increased, the fusing part is disconnected, and the first electrode terminal and/or the second electrode terminal are/is electrically disconnected with the electrode assembly, so that the electrode assembly is electrically disconnected with the outside, and the safety performance of the battery is further improved.

In a third aspect, the present application provides a battery including the battery cell provided in the second aspect of the present application.

In a fourth aspect, the present application provides a powered device comprising the battery provided in the third aspect of the present application, the battery being configured to provide electrical energy.

The embodiment of the application provides an end cover assembly for battery monomer, including end cover, first electrode terminal, second electrode terminal and first deformation. The first electrode terminal and the second electrode terminal are used for inputting or outputting electric energy and are arranged on the end cover, the hardness of the first electrode terminal is smaller than that of the end cover and is insulated from the end cover, the first electrode terminal is provided with a first connecting portion, and the first connecting portion is located on one side, facing the interior of the battery cell, of the end cover in the thickness direction of the end cover. First deformation welding is on first connecting portion, the base member material of first deformation is the same with the base member material of first electrode terminal, and set up with the end cover interval on the thickness direction of end cover, when free internal pressure of battery reaches the threshold value, first deformation moves towards the direction towards the end cover, so that first deformation and end cover contact, thereby pass through the end cover electricity with first electrode terminal and connect in second electrode terminal, form the protection circuit, with the short circuit of the free internal assembly of battery, the risk of having reduced the battery overcharge, the security performance of battery has been improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for a person skilled in the art to obtain other drawings based on the drawings without any creative effort.

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

FIG. 2 is a schematic diagram of a cell according to some embodiments of the present disclosure;

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

fig. 4 is a schematic structural view of a battery cell disclosed in some embodiments of the present application;

FIG. 5 is an exploded view of an end cap assembly as disclosed in some embodiments of the present application;

FIG. 6 is a cross-sectional view of an end cap assembly disclosed in some embodiments of the present application;

FIG. 7 is an enlarged partial view at A of the cross-sectional view of the endcap assembly shown in FIG. 6;

FIG. 8 is an exploded view of an end cap assembly according to further embodiments of the present application;

FIG. 9 is a cross-sectional view of an end cap assembly disclosed in other embodiments of the present application;

FIG. 10 is an enlarged partial view at B of the cross-sectional view of the endcap assembly shown in FIG. 9;

FIG. 11 is an enlarged partial view at C of the cross-sectional view of the end cap assembly shown in FIG. 9;

FIG. 12 is a schematic illustration of the construction of a second deformable member disclosed in some embodiments of the present application;

FIG. 13 is a schematic view of a second platen according to some embodiments of the present disclosure.

In the drawings, the drawings are not necessarily to scale.

Description of the labeling: 10-a box body; 11-a first part; 12-a second part; 13-a containment chamber; 20-a battery module; 30-a battery cell; 40-an end cap assembly; 41-end cap; 42-first electrode terminal; 421-a first connection; 4211-first weld hole; 43-a second electrode terminal; 431-a second connection; 4311-second weld hole; 4311a — first stage orifice; 4311 b-second stage orifice; 4311 c-step face; 44-a first deformation; 45-a second deformable member; 451-a weld; 452-a boss; 453-a connecting part; 46-a first seal; 47-a second seal; 48-a first enclosed space; 49-a second enclosed space; 50-a first platen; 501-a first pressing part; 502-a first fixed part; 51-a second platen; 511-a second pressing part; 512-second fixed part; 513-a second transition; 60-an electrode assembly; 61-a housing; 611-opening; 62-a first current collecting member; 63-a second current collecting member; 631-a fuse portion; 100-a battery; 1000-a vehicle; x-thickness direction of end caps.

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.

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 single battery of cylindricality battery, square battery monomer and laminate polymer battery monomer, this application embodiment is also not limited to this.

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

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive pole piece, a negative pole piece and a diaphragm. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece includes anodal mass flow body and anodal active substance layer, and anodal active substance layer coats in anodal mass flow body's surface, and the anodal mass flow body protrusion in the anodal mass flow body that has coated anodal active substance layer of uncoated anodal active substance layer, and the anodal mass flow body that does not coat anodal active substance layer is as anodal utmost point ear. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece comprises a negative pole current collector and a negative pole active substance layer, wherein the negative pole active substance layer is coated on the surface of the negative pole current collector, the negative pole current collector which is not coated with the negative pole active substance layer protrudes out of the negative pole current collector which is coated with the negative pole active substance layer, and the negative pole current collector which is not coated with the negative pole active substance layer is used as a negative pole lug. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fuse is not fused when a large current is passed, the number of the positive electrode tabs is multiple and the positive electrode tabs are stacked together, and the number of the negative electrode tabs is multiple and the negative electrode tabs are stacked together. The base film material of the diaphragm may be PP (polypropylene) or PE (polyethylene), etc.

The battery may be overcharged during charging, that is, the battery continues to be charged after being fully charged, which may cause the internal pressure of the battery to rise, deform or leak, so that the performance of the battery is significantly reduced and even safety problems such as explosion, fire and the like are caused.

Generally, in order to reduce the risk of overcharge of a battery, a deformation member is disposed on an end cap of a battery cell, and when the internal pressure of the battery cell reaches a threshold value, the deformation member is actuated, so that a positive electrode terminal and a negative electrode terminal are electrically connected through the end cap, thereby short-circuiting an electrode assembly in the battery cell.

The invention aims to improve the pressure resistance of a battery monomer, and the end cover adopts a base material with hardness greater than that of an electrode terminal. However, the inventors have found that when the base material of the deformable member is different from that of the end cap, it is difficult to ensure reliable connection by welding, and when the deformable member is made of the same base material as the end cap and has higher hardness, the manufacturing difficulty is increased.

In view of this, the inventor welds the deformation piece on electrode terminal, and when battery monomer internal pressure reached the threshold value, the deformation piece moved towards the end cover to be connected with the end cover electricity, thereby made positive electrode terminal and negative electrode terminal pass through the end cover electricity and be connected, the electrode subassembly short circuit in the battery monomer, reduced the risk of overcharging when strengthening battery monomer resistance to pressure, further improved the security performance 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. 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 view of a vehicle 1000 disclosed in some embodiments of the present application; 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.

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

Referring to fig. 2, fig. 2 is a schematic structural diagram of a battery 100 disclosed in some embodiments of the present application, where the battery 100 includes a battery cell 30 and a case 10, and the case 10 is used for accommodating the battery cell 30.

The case 10 is a component for accommodating the battery cell 30, the case 10 provides an accommodating space for the battery cell 30, 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 30. 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 be a hollow structure with one side open, and the open side of the second portion 12 is closed to the open side of the first portion 11, thereby forming the case 10 having the receiving space. The first portion 11 may have a hollow structure with one side open, the second portion 12 may have a plate-like structure, and the second portion 12 may cover the open 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 30 may be provided. If there are a plurality of battery cells 30, the plurality of battery cells 30 may be connected in series, in parallel, or in series-parallel, where in series-parallel refers to that the plurality of battery cells 30 are connected in series or in parallel. The battery modules 20 can be formed by connecting a plurality of battery cells 30 in series, in parallel, or in series-parallel, and the plurality of battery modules 20 are accommodated in the case 10 in series, in parallel, or in series-parallel. Or all the battery cells 30 may be directly connected in series or in parallel or in series-parallel, and the whole of all the battery cells 30 is accommodated in the case 10.

Referring to fig. 2 and 3, fig. 3 is a schematic structural view of a battery module 20 according to some embodiments of the present disclosure. Illustratively, the battery 100 includes a plurality of battery cells 30, the plurality of battery cells 30 constitute a battery module 20, and the plurality of battery modules 20 are accommodated in the case 10.

In some embodiments, the battery 100 may further include a bus member, and the plurality of battery cells 30 may be electrically connected to each other through the bus member, so as to connect the plurality of battery cells 30 in series, 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. 4, fig. 4 is a schematic structural diagram of a battery cell 30 disclosed in some embodiments of the present application. Battery cell 30 includes an electrode assembly 60, a housing 61, and an end cap assembly 40. The case 61 serves to receive the electrode assembly 60, and the case 61 has an opening 611.

The housing 61 may be a hollow structure with an opening 611 formed at one end. The housing 61 may be various shapes, such as a cylinder, a rectangular parallelepiped, or the like. The material of the housing 61 may be various, such as copper, iron, aluminum, steel, aluminum alloy, etc.

One or more electrode assemblies 60 may be provided in the case 61.

The electrode assembly 60 is a component in the battery cell 30 where electrochemical reactions occur. The electrode assembly 60 may include a positive electrode tab, a negative electrode tab, and a separator. The electrode assembly 60 may have a winding type structure formed by winding a positive electrode tab, a separator, and a negative electrode tab, or a lamination type structure formed by laminating a positive electrode tab, a separator, and a negative electrode tab.

The positive electrode sheet may include a positive electrode current collector and positive electrode active material layers coated on opposite sides of the positive electrode current collector. The negative electrode tab may include a negative electrode current collector and a negative electrode active material layer coated on opposite sides of the negative electrode current collector.

The electrode assembly 60 has a cathode tab, which may be a portion of the cathode sheet on which the cathode active material layer is not coated, and an anode tab, which may be a portion of the anode sheet on which the anode active material layer is not coated.

The battery cell 30 may further include an insulating member to separate the case 61 from the electrode assembly 60, by which the insulating separation of the case 61 from the electrode assembly 60 is accomplished. The insulating member is made of insulating material, and the insulating member can be made of insulating material such as plastic, rubber and the like.

The battery cell 30 may further include a pressure relief device, a component for relieving the pressure inside the battery cell 30, and when the pressure or temperature inside the battery cell 30 reaches a threshold value, the pressure inside the battery cell 30 is relieved through the pressure relief device. The pressure relief device may be a component provided on the end cap 41, or the housing 61 may function as the pressure relief device.

The end cap assembly 40 includes an end cap 41. The end cap 41 is a member that covers the opening 611 of the case 61 to isolate the internal environment of the battery cell 30 from the external environment. The cap 41 covers the opening 611 of the case 61, and the cap 41 and the case 61 together define a sealed space for accommodating the electrode assembly 60, the electrolyte, and other components. The shape of the end cap 41 can be adapted to the shape of the housing 61, for example, the housing 61 has a rectangular parallelepiped structure, the end cap 41 has a rectangular plate structure adapted to the housing 61, and for example, the housing 61 has a cylindrical structure, and the end cap 41 has a circular plate structure adapted to the housing 61. The material of the end cap 41 may be various, for example, copper, iron, aluminum, steel, aluminum alloy, etc., and the material of the end cap 41 may be the same as or different from that of the case 61.

Referring to fig. 5 and 6, fig. 5 is an exploded view of an end cap assembly 40 disclosed in some embodiments of the present application, and fig. 6 is a cross-sectional view of the end cap assembly 40 disclosed in some embodiments of the present application. The end cap assembly 40 includes an end cap 41, a first electrode terminal 42, a second electrode terminal 43, and a first deformation 44. The first electrode terminal 42 and the second electrode terminal 43 are used for inputting or outputting electric energy, and are both provided on the end cap 41, the first electrode terminal 42 has a hardness smaller than that of the end cap 41, and is insulated from the end cap 41, the first electrode terminal 42 has a first connection portion 421, and the first connection portion 421 is located on a side of the end cap 41 facing the inside of the battery cell 30 in the thickness direction X of the end cap 41. The first deformation piece 44 is welded to the first connection part 421, the base material of the first deformation piece 44 is the same as the base material of the first electrode terminal 42, and is spaced from the end cap 41 in the thickness direction X of the end cap 41, and when the internal pressure of the battery cell 30 reaches a threshold value, the first deformation piece 44 moves in a direction facing the end cap 41 so that the first deformation piece 44 and the end cap 41 are in contact with each other, whereby the first electrode terminal 42 is electrically connected to the second electrode terminal 43 through the first deformation piece 44 and the end cap 41.

The first electrode terminal 42 and the second electrode terminal 43 have opposite polarities, and when the first electronic terminal is a positive electrode terminal, the second electrode terminal 43 is a negative electrode terminal, for example, in the present embodiment, the first electrode terminal 42 is a negative electrode terminal, and the second electrode terminal 43 is a positive electrode terminal.

The hardness of the first electrode terminal 42 is less than that of the end cap 41, the material of the first electrode terminal 42 may be copper, aluminum alloy or other conductive material, and the material of the end cap 41 may be steel or the like having a hardness greater than that of the material used for the first electrode terminal 42. Illustratively, in the present embodiment, the material of the first electrode terminal 42 is copper, and the material of the end cap 41 is steel.

Hardness refers to the ability of a material to resist locally the penetration of a hard object into its surface, and can be measured using the measurement standards such as mohs hardness and brinell hardness, which are not specifically limited in this application.

The first electrode terminal 42 and the end cap 41 are insulated by providing an insulating member or coating an insulating layer at the joint of the first electrode terminal 42 and the end cap 41, for example, referring to fig. 6, the insulating member is provided at the joint of the first electrode terminal 42 and the end cap 41 to insulate the first electrode terminal 42 and the end cap 41, and a certain sealing effect is achieved. The second electrode terminal 43 and the end cap 41 may be insulated or electrically connected, and for example, referring to fig. 6, the second electrode terminal 43 and the end cap 41 are electrically connected.

Referring to fig. 6 and 7, fig. 7 is an enlarged partial view at a of the cross-sectional view of the end cap assembly 40 of fig. 6. The first electrode terminal 42 has a first connection portion 421, and the first connection portion 421 extends from an end portion of the first electrode terminal 42 located inside the battery cell 30 in a direction close to the second electrode terminal 43, is located on a side of the end cap 41 facing the inside of the battery cell 30, and has a gap with the end cap 41.

The first deformation piece 44 is welded on the first connection portion 421, and the welding mode may be a penetration welding mode, a splice welding mode, and the like, and the application does not specially limit this. In order to improve the reliability of the welding, the base material of the first deformation member 44 is the same as that of the first electrode terminal 42, and may be copper, aluminum, or other material satisfying manufacturability and electrical conductivity. Alternatively, the base material of the first electrode terminal 42 is copper, so the base material of the first transformation 44 is copper. Alternatively, the surfaces of the first electrode terminal 42 and the first transformation member 44 may have protective layers.

The first deforming member 44 is provided at a distance from the end cap 41 in the thickness direction X of the end cap 41 so that the end cap 41 and the first deforming member 44 are insulated.

According to the embodiment of the present application, the end cap 41 has a hardness greater than that of the first electrode terminal 42, enhancing the pressure resistance of the battery cell 30. The base material of the first deformation piece 44 is the same as that of the first electrode terminal 42, so that the first deformation piece 44 can be electrically connected to the first connection part 421 by welding. When the internal pressure of the battery cell 30 reaches a threshold value, the first deformation member 44 moves in a direction facing the end cap 41, so that the first deformation member 44 is in contact with the end cap 41, the first electrode terminal 42 is electrically connected to the second electrode terminal 43 through the end cap 41, a protection circuit is formed, and an electrode assembly 60 (not shown in the figure) inside the battery cell 30 is short-circuited, so that the risk of overcharging of the battery is reduced, and the safety performance of the battery is improved.

Referring to fig. 6, the second electrode terminal 43 is electrically connected to the end cap 41.

The second electrode terminal 43 and the end cap 41 may be electrically connected through a conductive plastic or a metal block, etc., and the present application is not limited thereto.

Optionally, in the embodiment of the present application, the second electrode terminal 43 is a positive electrode terminal, and after being electrically connected to the end cap 41, the end cap 41 is positively charged, so that the possibility of corrosion of the end cap 41 and the housing 61 is reduced.

According to the embodiment of the application, the second electrode terminal 43 is electrically connected with the end cover 41, when the internal pressure of the battery cell 30 reaches a threshold value, the first deformation piece 44 moves towards the direction facing the end cover 41, so that the first deformation piece 44 is in contact with the end cover 41, and an electrical connection route from the first electrode terminal 42 to the first deformation piece 44 to the end cover 41 and then to the second electrode terminal 43 is formed, so that the internal components of the battery are short-circuited, the risk of overcharging of the battery is reduced, and the structure is simple.

Referring to fig. 8 and 9, fig. 8 is an exploded view of an end cap assembly 40 disclosed in other embodiments of the present application, and fig. 9 is a cross-sectional view of the end cap assembly 40 disclosed in other embodiments of the present application. The second electrode terminal 43 has a hardness less than that of the end cap 41 and is insulated from the end cap 41, the second electrode terminal 43 has a second connection portion 431, the second connection portion 431 is located on a side of the end cap 41 facing the inside of the battery cell 30 in the thickness direction X of the end cap 41, the second connection portion 431 is used for welding a second deformation member 45, and a base material of the second deformation member 45 is the same as that of the second electrode terminal 43 and is spaced from the end cap 41 in the thickness direction X; when the internal pressure of the battery cell 30 reaches a threshold value, the second deformation member 45 is moved in a direction facing the end cap 41 to bring the second deformation member 45 into contact with the end cap 41, thereby electrically connecting the first electrode terminal 42 to the second electrode terminal 43 through the first deformation member 44, the end cap 41, and the second deformation member 45.

The material of the second electrode terminal 43 may be a conductive material such as aluminum, copper, aluminum alloy, etc., and the material of the end cap 41 may be a material such as steel, etc. with a hardness greater than that of the second electrode terminal 43.

The insulation of the second electrode terminal 43 and the end cap 41 may be achieved by providing an insulating member or coating an insulating layer at the junction of the end cap 41 and the second electrode terminal 43, for example, referring to fig. 9, the insulating member is provided between the second electrode terminal 43 and the end cap 41. Optionally, the insulating part is made of rubber, and plays a role in insulation and sealing.

Referring to fig. 9 and 10, fig. 10 is an enlarged partial view at B of the cross-sectional view of the end cap assembly 40 shown in fig. 9. The second electrode terminal 43 has a second connection part 431, and the second connection part 431 extends from an end of the second electrode terminal 43 located inside the battery cell 30 in a direction close to the first electrode terminal 42, is located on a side of the end cap 41 facing the inside of the battery cell 30, and has a gap with the end cap 41.

The second deformation piece 45 is welded on the second connection portion 431, and the welding mode may be a penetration welding mode, a splicing welding mode, and the like, and the application does not specially limit the welding mode. In order to improve the reliability of welding, the base material of the second deformation member 45 is the same as that of the second electrode terminal 43, and may be an aluminum alloy, aluminum, or other material satisfying manufacturability and electrical conductivity. Alternatively, the base material of the second electrode terminal 43 is aluminum, so the base material of the second transformation member 45 is aluminum. Alternatively, the surfaces of the second electrode terminal 43 and the second deforming member 45 may have a protective layer or other outer layer structure.

The second deforming member 45 is provided at a distance from the end cap 41 in the thickness direction X of the end cap 41, so that the end cap 41 and the second deforming member 45 are insulated.

According to the embodiment of the application, the second electrode terminal 43 is insulated from the end cover 41 and is provided with the second connecting portion 431 to weld the second deformation piece 45, the second deformation piece 45 and the end cover 41 are arranged at intervals, when the internal pressure of the battery cell 30 reaches a threshold value, the first deformation piece 44 and the second deformation piece 45 both move towards the direction facing the end cover 41, so that the first electrode terminal 42 and the second electrode terminal 43 are electrically connected through the end cover 41, a protection loop is formed, and the risk of overcharge of the battery is reduced.

Referring to fig. 8, 9, 10 and 11, fig. 11 is an enlarged partial view at C of the cross-sectional view of the end cap assembly 40 shown in fig. 9. The first connection portion 421 is provided with a first welding hole 4211 corresponding to the shape of the first deformation piece 44, and when the first deformation piece 44 moves in a direction facing the end cap 41, the first deformation piece 44 at least partially passes through the first welding hole 4211 and is electrically connected to the end cap 41. The second connection portion 431 is provided with a second welding hole 4311 corresponding to the shape of the second deformation piece 45, and when the second deformation piece 45 moves in a direction facing the end cap 41, the second deformation piece 45 at least partially passes through the second welding hole 4311 and is electrically connected with the end cap 41.

Be equipped with first welding hole 4211 on first connecting portion 421, first welding hole 4211 is corresponding with first deformation piece 44 shape, and first welding hole 4211 needs to satisfy at least, and when first deformation piece 44 warp, first deformation piece 44 can reach end cover 41 through first welding hole 4211 at least partially. Optionally, when the first deformation piece 44 is circular on the whole, the first welding hole 4211 is a circular hole, and when the first deformation piece 44 is square, the first welding hole 4211 is a square hole, so as to reduce the possibility that the first deformation piece 44 is blocked when deformed. Illustratively, referring to fig. 8 and 11, the first welding hole 4211 and the first deformation piece 44 are both circular, and the first deformation piece 44 and the first welding hole 4211 are coaxially arranged and welded.

The second connecting portion 431 is provided with a second welding hole 4311, the shape of the second welding hole 4311 corresponds to that of the second deformation piece 45, the second welding hole 4311 at least needs to be satisfied, and when the second deformation piece 45 deforms, at least part of the second deformation piece 45 can reach the end cover 41 through the second welding hole 4311. Optionally, when the second deformation piece 45 is circular in whole, the second welding hole 4311 is a circular hole, and when the second deformation piece 45 is square, the second welding hole 4311 is a square hole, so as to reduce the possibility that the second deformation piece 45 is blocked when deformed. For example, referring to fig. 8 and 10, the second welding hole 4311 and the second deforming member 45 are both circular, and the second deforming member 45 and the second welding hole 4311 are coaxially disposed and welded.

According to the embodiment of the application, the first connection portion 421 is provided with a first welding hole 4211 corresponding to the shape of the first deformation piece 44, and the second connection portion 431 is provided with a second welding hole 4311 corresponding to the shape of the second deformation piece 45, so that the first deformation piece 44 and the second deformation piece 45 can be welded with the first connection portion 421 and the second connection portion 431 respectively, and a space for movement is provided, so that when the internal pressure of the battery cell 30 reaches a threshold value, the first deformation piece 44 and the second deformation piece 45 can partially pass through the first welding hole 4211 and the second welding hole 4311, and are in contact with and electrically connected with the end cover 41.

Referring to fig. 10 and 11, each of the first welding hole 4211 and the second welding hole 4311 includes a first-stage hole 4311a and a second-stage hole 4311b which are coaxially disposed, the second-stage hole 4311b is closer to the end cap 41 than the first-stage hole 4311a, the diameter of the second-stage hole 4311b is smaller than that of the first-stage hole 4311a, a step surface 4311c is formed between a hole wall of the first-stage hole 4311a and a hole wall of the second-stage hole 4311b, the first deforming member 44 is welded to the step surface 4311c of the first welding hole 4211, and the second deforming member 45 is welded to the step surface 4311c of the second welding hole 4311.

According to this application embodiment, first welding hole 4211 and second welding hole 4311 are the step hole for it forms step face 4311c, first deformation piece 44 and second deformation piece 45 weld in step face 4311c, and it is spacing by the lateral wall of first order hole 4311a, make first deformation piece 44 and first connecting portion 421 connect more reliably, second deformation piece 45 and second connecting portion 431 connect more reliably, first connecting portion 421 and second connecting portion 431 at least partially hold in first order hole 4311a, the energy density of battery has been improved.

Referring to fig. 10, 11 and 12, fig. 12 is a schematic structural view of a second deforming member 45 disclosed in some embodiments of the present application. The first deforming part 44 and the second deforming part 45 are both turning pieces, and each turning piece comprises a welding part 451, a boss 452 and a connecting part 453 located between the welding part 451 and the boss 452. The welding part 451 is positioned at the edge of the turnover piece, the boss 452 is positioned in the central area of the turnover piece, and the connecting part 453 is used for connecting the welding part 451 and the boss 452; when the interior of the battery cell 30 reaches the threshold value, the flip piece is moved in a direction facing the end cap 41 so that the boss 452 comes into contact with the end cap 41.

Optionally, in the thickness direction X of the end cap 41, the thickness of the welding portion 451 is greater than the thickness of the connecting portion 453, the thickness of the boss 452 is greater than the thickness of the connecting portion 453, and the connecting portion 453 is weakest, so that the connecting portion 453 is most easily deformed to realize the flap motion.

According to the embodiment of the application, the turnover sheet provides the welding part 451, so that the turnover sheet is welded with the first connecting part 421 or the second connecting part 431, the connecting part 453 is deformed when the internal pressure of the battery cell 30 reaches a threshold value, so that the first deforming part 44 or the second deforming part 45 can move towards the end cover 41 to be electrically connected with the end cover 41, the boss 452 increases the contact area between the turnover sheet and the end cover 41, the current overflowing area during electrical connection is increased, and the heat generation at the contact part is reduced.

In some embodiments of the present application, the hardness of the base material of the first deforming member 44 is greater than that of the base material of the second deforming member 45, and the area of the first deforming member 44 is greater than that of the second deforming member 45.

Since the first deformation piece 44 and the first connection portion 421 are welded and the second deformation piece 45 and the second connection portion 431 are welded, the base material of the first deformation piece 44 and the base material of the first connection portion 421 are the same and the base material of the second deformation piece 45 and the base material of the second connection portion 431 are the same in order to secure the welding. Optionally, the base materials of the first connecting portion 421 and the first deforming member 44 are copper, and the base materials of the second connecting portion 431 and the second deforming member 45 are aluminum, and in view of the fact that the pressed areas are the same, the second deforming member 45 is more easily turned or deformed than the first deforming member 44, so that in order to reduce the time difference between the actions of the first deforming member 44 and the second deforming member 45, when the internal pressure of the battery cell 30 reaches the threshold value, the internal electrode assembly 60 is more timely short-circuited, the area of the first deforming member 44 is increased, and the area of the first deforming member 44 is larger than the pressed area of the second deforming member 45.

According to this application embodiment, the area of first deformation 44 is greater than the area of second deformation 45, when battery monomer 30 internal pressure reached the threshold value, has improved the possibility that first deformation 44 and second deformation 45 can move towards end cover 41 simultaneously for the inside subassembly of battery monomer 30 can be more in time by the short circuit, thereby has further improved the security performance of battery.

In some embodiments of the present application, the hardness of the base material of the first deforming member 44 is greater than that of the base material of the second deforming member 45, and the minimum thickness of the connecting portion 453 of the first deforming member 44 is less than that of the connecting portion 453 of the second deforming member 45.

Optionally, the base materials of the first connecting portion 421 and the first deforming member 44 are copper, and the base materials of the second connecting portion 431 and the second deforming member 45 are aluminum, and in view of the same thickness, the second deforming member 45 is more easily turned or deformed compared with the first deforming member 44, so that in order to reduce the time difference between the actions of the first deforming member 44 and the second deforming member 45, when the internal pressure of the battery cell 30 reaches the threshold value, the internal electrode assembly 60 thereof can be more timely short-circuited, the thickness of the first deforming member 44 is reduced, and the turning difficulty of the first deforming member 44 is reduced.

According to the embodiment of the application, the minimum thickness of the connecting part 453 of the first deforming part 44 is smaller than the minimum thickness of the connecting part 453 of the second deforming part 45, so that the possibility that the first deforming part 44 and the second deforming part 45 can act towards the end cover 41 when the internal pressure of the battery cell 30 reaches a threshold value is improved, components inside the battery cell 30 can be short-circuited more timely, and the safety performance of the battery is further improved.

Referring to fig. 9, 10 and 11, the end cap assembly 40 includes a first sealing member 46 and a second sealing member 47, the first sealing member 46 is provided between the first deforming member 44 and the end cap 41 in the thickness direction X to form a first sealed space 48, and the second sealing member 47 is provided between the second deforming member 45 and the end cap 41 to form a second sealed space 49.

Optionally, the inner diameter of the first sealing member 46 is larger than the diameter of the second-stage hole 4311b of the first welding hole 4211, so that the first sealing member 46 and the first connection portion 421 have a larger contact area, and a groove for installing the first sealing member 46 may be correspondingly formed on a surface of the end cover 41 facing the inside of the battery cell 30 and/or a surface of the first connection portion 421 facing the end cover 41, so as to prevent a gap from being generated between the two and causing a sealing failure.

The first seal 46 may be rubber or other material that can insulate and meet sealing properties.

Optionally, the inner diameter of the second sealing element 47 is larger than the diameter of the second-stage hole 4311b of the second welding hole 4311, so that the second sealing element 47 and the second connection portion 431 have larger contact areas, and a surface of the end cover 41 facing the inside of the battery cell 30 and/or a surface of the second connection portion 431 facing the end cover 41 may be correspondingly provided with a groove for mounting the second sealing element 47, so as to avoid a gap between the two and cause a sealing failure.

The second seal 47 may be rubber or other material that can insulate and meet the sealing properties.

According to the embodiment of the application, the first sealing member 46 and the second sealing member 47 are arranged to form the first sealed space 48 and the second sealed space 49, when the internal pressure of the battery cell 30 reaches a threshold value, the pressure of the first deformation member 44 and the second deformation member 45 close to the end cover 41 is smaller than the pressure of the first deformation member 44 and the second deformation member 45 far away from the end cover 41, so that a pressure difference is generated, the first deformation member 44 and the second deformation member 45 are forced to act, and the contact with the end cover 41 is realized.

Referring to fig. 9, 10, 11 and 13, fig. 13 is a schematic structural view of a second presser plate 51 in some embodiments of the present application. The end cap assembly 40 includes a first pressing plate 50, the first pressing plate 50 being insulated from the first connection 421; the first pressing plate 50 includes a first pressing portion 501 (not shown in the figure) and a first fixing portion 502 (not shown in the figure), in the thickness direction X of the end cover 41, the first pressing portion 501 is located on a side of the first connecting portion 421 away from the end cover 41, and presses against the first connecting portion 421, so that the first sealing element 46 is compressed; the first fixing portion 502 is connected to the end cap 41 to fix the first pressing plate 50 to the end cap 41; and/or the end cap assembly 40 includes a second pressing plate 51, the second pressing plate 51 being insulated from the second connection portion 431; the second pressing plate 51 includes a second pressing portion 511 and a second fixing portion 512, in the thickness direction X of the end cover 41, the second pressing portion 511 is located on a side of the second connecting portion 431 away from the end cover 41, and presses the second connecting portion 431, so that the second sealing member 47 is compressed; the second fixing portion 512 is connected to the end cap 41 to fix the second pressing plate 51 to the end cap 41.

The first pressure plate 50 is insulated from the first connection portion 421, and the second pressure plate 51 is insulated from the second connection portion 431, which can be realized by coating the surface of the first pressure plate 50 or the second pressure plate 51 with an insulating material such as insulating rubber or plastic, or by other methods such as adding an insulating member, and the application is not limited thereto.

The first fixing portion 502 and the end cap 41, and the second fixing portion 512 and the end cap 41 may be connected by welding, bonding, riveting, or the like, which is not limited in this application. Optionally, the fixing portion 512 and the end cap 41 are welded.

According to the embodiment of the application, the first pressing part 501 presses the first connecting part 421 along the direction close to the end cover 41, and the second pressing part 511 presses the second connecting part 431 along the direction close to the end cover 41, so that the first sealing element 46 and the second sealing element 47 are compressed, the risk of sealing failure of the first sealed space 48 and the second sealed space 49 is reduced, and the possibility of action of the first deformation part 45 and the second deformation part 45 when the internal pressure of the battery cell 30 reaches the threshold value is improved.

In some embodiments, the first pressing plate 50 and/or the second pressing plate 51 are stepped pressing plates, for example, referring to fig. 13, the second pressing plate 51 is a stepped pressing plate and includes a second transition portion 513, and the second transition portion 513 is located between the second pressing portion 511 and the second fixing portion 512 for connecting the second pressing portion 511 and the fixing portion 512.

Optionally, the surfaces of the first pressing plate 50 and/or the second pressing plate 51 contacting the first connection portion 421 or the second connection portion 431 are provided with an insulating material, so that the first pressing plate 50 and the first connection portion 421 are insulated, and the second pressing plate 51 and the second connection portion 431 are insulated.

According to the embodiment of the application, the step-shaped pressing plate provides a larger stress area for the pressing part and provides a sufficient connection area for the fixing part, so that the connection between the fixing part and the end cover 41 is more reliable, the transition part is connected with the pressing part and the fixing part, the structure of the pressing plate is more stable, and the possibility of sealing failure of the first closed space 48 and the second closed space 49 is further reduced.

Referring again to fig. 4, the battery cell 30 further includes a first current collecting member 62 and a second current collecting member 63, the first current collecting member 62 and/or the second current collecting member 63 having a fusing portion 631, the fusing portion 631 being configured to be disconnected when the first electrode terminal 42 and the second electrode terminal 43 are electrically connected, such that the first electrode terminal 42 and/or the second electrode terminal 43 are electrically disconnected from the electrode assembly 60.

The first current collecting member 62 is connected to an end of the first electrode terminal 42 located inside the battery cell 30 such that the first electrode terminal 42 is electrically connected with the electrode assembly 60. The second current collecting member 63 is connected to an end of the second electrode terminal 43 located inside the battery cell 30 such that the second electrode terminal 43 is electrically connected with the electrode assembly 60.

The material of the first current collecting member 62 and the second current collecting member 63 may be aluminum, copper, aluminum alloy, or other conductive material, and the present application is not limited thereto.

The first and second current collecting members 62 and 63 may include terminal connection parts for connecting electrode terminals and tab connection parts for connecting tabs extending from the electrode members.

The connection may be by welding, riveting, bonding or other means that can meet the connection requirements, and this application is not particularly limited.

Illustratively, referring to fig. 4, the second current collecting member 63 has a fusing portion 631.

The fusing portion 631 may be formed by recessing an edge of the current collecting member, forming an opening in the current collecting member, or using a different material or thickness at the fusing portion 631.

The number of the fusing part 631 may be one or more.

According to the embodiment of the present application, the first electrode terminal 42 is connected to the first current collecting member 62, and the second electrode terminal 43 is connected to the second current collecting member 63, so that the electrode assembly 60 is electrically connected to an external electrical device or power source, when the internal pressure of the battery cell 30 reaches a threshold value, the first electrode terminal 42 and the second electrode terminal 43 are electrically connected through the end cap 41, and at this time, the current passing through the first current collecting member 62 and the second current collecting member 63 increases, the fuse 631 is disconnected, and the electrical connection between the first electrode terminal 42 and/or the second electrode terminal 43 and the electrode assembly 60 is disconnected, so that the electrical connection between the electrode assembly 60 and the outside is disconnected, and the safety performance of the battery is further improved.

Referring to fig. 4 to 13, an end cap assembly 40 including an end cap 41, a first electrode terminal 42, a second electrode terminal 43, and a first deformation 44 is provided in some embodiments of the present application. The first electrode terminal 42 and the second electrode terminal 43 are used for inputting or outputting electric energy, and are both provided on the end cap 41, the first electrode terminal 42 has a hardness smaller than that of the end cap 41, and is insulated from the end cap 41, the first electrode terminal 42 has a first connection portion 421, and the first connection portion 421 is located on a side of the end cap 41 facing the inside of the battery cell 30 in the thickness direction X of the end cap 41. The first deformation piece 44 is welded to the first connection part 421, the base material of the first deformation piece 44 is the same as the base material of the first electrode terminal 42, and is spaced from the end cap 41 in the thickness direction X of the end cap 41, and when the internal pressure of the battery cell 30 reaches a threshold value, the first deformation piece 44 moves in a direction facing the end cap 41 so that the first deformation piece 44 contacts the end cap 41, whereby the first electrode terminal 42 is electrically connected to the second electrode terminal 43 through the end cap 41 and the first deformation piece 44.

The second electrode terminal 43 has a hardness less than that of the end cap 41 and is insulated from the end cap 41, the second electrode terminal 43 has a second connection portion 431, the second connection portion 431 is located on one side of the end cap 41 facing the inside of the battery cell 30 in the thickness direction X of the end cap 41, the second connection portion 431 is used for welding a second deformation member 45, and the base material of the second deformation member 45 is the same as that of the second electrode terminal 43 and is spaced from the end cap 41 in the thickness direction X; when the internal pressure of the battery cell 30 reaches the threshold value, the second deformation member 45 is moved in a direction facing the end cap 41 so that the second deformation member 45 and the end cap 41 are brought into contact, thereby electrically connecting the first electrode terminal 42 to the second electrode terminal 43 through the end cap 41.

While the application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims (14)

1. An end cap assembly for a battery cell, comprising:

an end cap;

the first electrode terminal and the second electrode terminal are used for inputting or outputting electric energy, the first electrode terminal and the second electrode terminal are arranged on the end cover, the hardness of the first electrode terminal is smaller than that of the end cover and is insulated from the end cover, the first electrode terminal is provided with a first connecting part, and the first connecting part is positioned on one side, facing the interior of the battery cell, of the end cover in the thickness direction of the end cover; and

first deformation, the welding is in on the first connecting portion, the base member of first deformation with the base member of first electrode terminal is the same, and in the thickness direction with the end cover interval sets up when free internal pressure of battery reaches the threshold value, first deformation orientation towards the direction action of end cover, so that first deformation with the end cover contact, thereby will first electrode terminal passes through first deformation the end cover electricity connect in second electrode terminal.

2. The end cap assembly of claim 1, wherein the second electrode terminal is electrically connected to the end cap.

3. The end cap assembly according to claim 1, wherein the second electrode terminal has a hardness less than that of the end cap and is insulated from the end cap, the second electrode terminal has a second connecting portion on a side of the end cap facing the inside of the battery cell in a thickness direction of the end cap, the second connecting portion is used for welding a second deformation member having a base material identical to that of the second electrode terminal and spaced from the end cap in the thickness direction;

when the internal pressure of the battery cell reaches the threshold value, the second deformation piece moves towards the direction facing the end cover, so that the second deformation piece is in contact with the end cover, and the first electrode terminal is electrically connected to the second electrode terminal through the first deformation piece, the end cover and the second deformation piece.

4. The end cap assembly according to claim 3, wherein the first connecting portion is provided with a first welding hole corresponding to the shape of the first deformation piece, and when the first deformation piece moves towards the direction facing the end cap, the first deformation piece at least partially penetrates through the first welding hole and is electrically connected with the end cap;

the second connecting portion are provided with second welding holes corresponding to the shapes of the second deformation pieces, and when the second deformation pieces face the direction of the end cover to move, at least parts of the second deformation pieces penetrate through the second welding holes and are electrically connected with the end cover.

5. The end cap assembly of claim 4, wherein the first and second welded holes each comprise coaxially disposed first and second stage holes, the second stage hole being closer to the end cap than the first stage hole, the second stage hole having a diameter smaller than the first stage hole, a step surface being formed between a hole wall of the first stage hole and a hole wall of the second stage hole, the first deformable member being welded on the step surface of the first welded hole, the second deformable member being welded on the step surface of the second welded hole.

6. The end cap assembly of claim 3, wherein the first deforming member and the second deforming member are both upset pieces, the upset pieces including welds, bosses, and connecting portions between the welds and the bosses;

the welding part is located the edge of upset piece, the boss is located the central zone of upset piece, connecting portion are used for connecting the welding part with the boss, work as battery monomer is inside to reach when the threshold value, the upset piece towards the direction action of end cover makes the boss with the end cover contact.

7. The end cap assembly of claim 6, wherein the hardness of the base material of the first deformation member is greater than the hardness of the base material of the second deformation member, and the projected area of the first deformation member is greater than the projected area of the second deformation member in the thickness direction of the end cap.

8. The end cap assembly of claim 6, wherein a hardness of a base material of the first deforming member is greater than a hardness of a base material of the second deforming member, and a minimum thickness of the connecting portion of the first deforming member is less than a minimum thickness of the connecting portion of the second deforming member.

9. An end cap assembly according to claim 3, including a first seal member and a second seal member, the first seal member being disposed between the first deformable member and the end cap in the thickness direction to form a first enclosed space, the second seal member being disposed between the second deformable member and the end cap to form a second enclosed space.

10. The end cap assembly of claim 9, wherein the end cap assembly includes a first compression plate insulated from the first connection;

the first pressing plate comprises a first abutting part and a first fixing part, and in the thickness direction of the end cover, the first abutting part is positioned on one side of the first connecting part, which is far away from the end cover, and abuts against the first connecting part so that the first sealing element is compressed; the first fixing part is connected to the end cover so as to fix the first pressing plate to the end cover; and/or

The end cover assembly comprises a second pressing plate, and the second pressing plate is insulated from the second connecting part;

the second pressing plate comprises a second pressing part and a second fixing part, and the second pressing part is positioned on one side, away from the end cover, of the second connecting part in the thickness direction of the end cover and presses the second connecting part so as to compress the second sealing element; the second fixing portion is connected to the end cap to fix the second pressing plate to the end cap.

11. A battery cell, comprising:

the end cap assembly of any one of claims 1-10;

an electrode assembly;

a case for accommodating the electrode assembly, the case having an opening, the end cap for covering the opening.

12. The battery cell according to claim 11, wherein the battery cell includes a first current collecting member and a second current collecting member, the first current collecting member and the first electrode terminal being connected at ends inside the battery cell to electrically connect the first electrode terminal with the electrode assembly;

a second current collecting member connected to an end of the second electrode terminal located inside the battery cell such that the second electrode terminal is electrically connected to the electrode assembly;

the first current collecting member and/or the second current collecting member has a fuse portion configured to be disconnected when the first electrode terminal and the second electrode terminal are electrically connected, such that the first electrode terminal and/or the second electrode terminal are electrically disconnected from the electrode assembly.

13. A battery comprising the battery cell of claim 11 or 12.

14. A powered device comprising the battery of claim 13, the battery for providing electrical energy.

Images