CN219321476U - End cover assembly, battery cell, battery and power utilization device - Google Patents

Abstract

The application discloses an end cover assembly, a battery cell, a battery and an electric device. The end cover assembly is used for a battery cell and comprises an end cover and an electrode terminal, wherein the end cover is provided with an electrode leading-out hole; the electrode terminal comprises a connecting part and a terminal main body, and the terminal main body protrudes from the connecting part and is at least partially accommodated in the electrode lead-out hole; the connecting part is provided with the groove, so that the weight of the battery monomer is reduced, the internal space of the battery monomer is saved, and the energy density of the battery monomer is improved.

Description

End cover assembly, battery cell, battery and power utilization device

Technical Field

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

Background

Battery cells are widely used in electronic devices such as cellular phones, notebook computers, battery cars, electric vehicles, electric airplanes, electric ships, electric toy vehicles, electric toy ships, electric toy airplanes, electric tools, and the like. The battery cells may include cadmium-nickel battery cells, hydrogen-nickel battery cells, lithium ion battery cells, secondary alkaline zinc-manganese battery cells, and the like.

In the development of battery technology, how to increase the energy density of a battery cell is one research direction in battery technology.

Disclosure of Invention

The application provides an end cover assembly, a battery cell, a battery and an electric device, which can improve the energy density of the battery cell.

In a first aspect, embodiments of the present application provide an end cap assembly for a battery cell, the end cap assembly including an end cap and an electrode terminal, the end cap having an electrode lead-out hole; the electrode terminal comprises a connecting part and a terminal main body, and the terminal main body protrudes from the connecting part and is at least partially accommodated in the electrode lead-out hole; the connecting part is provided with a groove.

In the scheme, the terminal main body is accommodated in the electrode extraction hole of the end cover, and electric energy is extracted through the terminal main body; through set up the recess at connecting portion, can hold battery cell's electrode terminal's utmost point ear or other parts in the recess, not only alleviateed battery cell's weight, saved battery cell's inner space moreover, improved battery cell's energy density.

In some embodiments, the connection portion includes a first connection sub-portion and a second connection sub-portion, the second connection sub-portion being connected between the terminal body and the first connection sub-portion, the second connection sub-portion having a thickness less than a thickness of the first connection sub-portion to form the recess.

In the scheme, the terminal main body is connected with the thicker first connecting sub-part, so that the connection strength between the terminal main body and the connecting part can be increased, and the stability of the terminal main body is improved.

In some embodiments, the surface of the connection part, facing the electrode assembly of the battery cell, is provided with a groove, so that the tab or other parts of the electrode assembly can be conveniently accommodated in the groove, the process preparation is convenient, and the production efficiency is improved.

In some embodiments, the surface of the first connector facing the end cover and the surface of the second connector facing the end cover are flush, so that the bearing capacity of the connecting part on the end cover can be improved, and the strength of the end cover assembly is enhanced.

In some embodiments, in the thickness direction of the end cover, the thickness of the second connector part is H1, and the thickness of the first connector part is H2, so that H1 is more than or equal to 1/5H2, H1 is more than or equal to 4/5H2, the weight and the internal capacity of the battery cell can be reduced, and the strength of the second connector part can be ensured.

In some embodiments, the first connector sub-portion and the second connector sub-portion are arranged along a first direction; in the second direction, at least one end of the second connecting sub-part exceeds the first connecting sub-part, and the first direction, the second direction and the thickness direction of the end cover are perpendicular to each other.

In the scheme, at least one end of the second connecting sub-part exceeds the first connecting sub-part, so that the weight of the connecting part can be further reduced, the internal space of the battery unit is further saved, and the energy density of the battery unit is improved.

In some embodiments, the number of the second connection sub-portions is two, and the two second connection sub-portions are respectively located at two sides of the first connection sub-portion along the first direction; the electrode terminal is provided with a weight-reducing groove which is positioned at one side of the first connecting sub-part along the second direction and is surrounded by the first connecting sub-part and the two second connecting sub-parts.

In the scheme, the two second connecting sub-parts are respectively positioned at the two sides of the first connecting sub-part along the first direction, so that one end cover assembly can be connected with two electrode assemblies simultaneously, and the energy density of the battery cell is improved. The weight reduction groove is formed by enclosing the first connecting sub-part and the two second connecting sub-parts, so that the weight of the end cover assembly can be reduced, the internal space of the battery unit is saved, the energy density of the battery unit is further improved, and more connecting spaces can be further improved for parts connected with the second connecting sub-parts.

In some embodiments, the end cap assembly further comprises a seal disposed around the terminal body, at least a portion of the seal being sandwiched between the end cap and the connection portion, a projection of the weight-reducing slot not overlapping a projection of the seal in a thickness direction of the end cap.

In the scheme, the sealing element can enhance the sealing effect between the end cover and the electrode terminal, reduce the probability of leakage of the battery monomer and improve the safety performance of the battery monomer. In the thickness direction of the end cover, the projection of the weight reduction groove is not overlapped with the projection of the sealing element, so that the compression amount of the sealing element can be improved, and the safety performance of the battery cell is further improved.

In some embodiments, the connection portion includes a tab connection section and a fusing section, the fusing section being located between the tab connection section and the terminal body, the tab connection section being for connecting the tabs of the electrode assembly.

In the scheme, through setting up the section of fusing for battery monomer can in time fuse under outer short operating condition, is difficult for blasting on fire, improves the free security performance of battery.

In some embodiments, the end cap assembly further comprises a seal disposed around the terminal body, at least a portion of the seal being sandwiched between the end cap and the connection portion, a projection of the seal not overlapping a projection of the groove in a thickness direction of the end cap.

In the scheme, the sealing element can enhance the sealing effect between the end cover and the electrode terminal, reduce the probability of leakage of the battery monomer and improve the safety performance of the battery monomer. In the thickness direction of the end cover, the projection of the sealing element is not overlapped with the projection of the groove, so that the compression amount of the sealing element can be increased, and the safety performance of the battery cell is further improved.

In a second aspect, embodiments of the present application provide a battery cell comprising a housing having an opening, an electrode assembly, and an end cap assembly of any of the above embodiments; the electrode assembly is accommodated in the case; the end cover is used for covering the opening, and the connecting part is positioned in the battery cell.

In some embodiments, the electrode assembly has tabs connected to the connection portion, and at least a portion of the tabs are received in the grooves, thereby not only reducing the weight of the battery cells, but also saving the occupied space of the tabs and improving the energy density of the battery cells.

In some embodiments, the tab includes a horizontal segment directly connected to the connection portion, and in a thickness direction along the end cover, a thickness of the horizontal segment is less than or equal to a depth of the groove, so that an occupied space of the tab can be further saved.

In a third aspect, embodiments of the present application provide a battery comprising a battery cell according to any one of the embodiments described above.

In a fourth aspect, an embodiment of the present application provides an electrical device, including a battery cell according to any one of the foregoing embodiments, where the battery cell is configured to provide electrical energy.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed 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 that other drawings may be obtained according to the drawings without inventive effort for a person skilled in the art.

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

fig. 2 is a schematic structural view of a battery according to some embodiments of the present application;

fig. 3 is a schematic view of the structure of the battery module shown in fig. 2;

FIG. 4 is a schematic diagram of an exploded structure of a battery cell according to some embodiments of the present application;

FIG. 5 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application;

FIG. 6 is a schematic structural view of a flip assembly according to some embodiments of the present application;

FIG. 7 is a schematic structural view of a connection portion according to some embodiments of the present application;

FIG. 8 is a schematic view of the connection portion shown in FIG. 6 at another angle;

FIG. 9 is an enlarged schematic view of portion A of FIG. 8;

FIG. 10 is a schematic view of a connection portion according to other embodiments of the present application;

FIG. 11 is a schematic view of another angle of the connecting portion shown in FIG. 10;

FIG. 12 is a schematic view of a connection portion according to further embodiments of the present application;

FIG. 13 is a schematic view of a connection portion according to further embodiments of the present application;

FIG. 14 is a schematic view of another angle of the connecting portion shown in FIG. 13;

FIG. 15 is a top view of a battery cell according to some embodiments of the present application;

fig. 16 is a partial schematic view of a battery cell according to some embodiments of the present application.

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

Reference numerals illustrate:

a vehicle 1000; a battery 100; a controller 200; a motor 300; a case 10; an upper cover 10a; a lower cover 10b; a battery module 400; a battery cell 20; a housing 22; an end cap 21; an electrode terminal 26; an electrode assembly 23; a main body 231; a tab 232; a vertical section 232a; a horizontal segment 232b; an end cap assembly 500; an electrode lead-out hole 21a; a connection portion 30; a groove 30a; a first connection sub-section 31; a second connector sub-portion 32; a tab connection section 321; a fuse section 322; a through hole 32a; a weight-reducing groove 30b; a terminal body 40; a seal 41; a thickness direction X; a first direction Y; a second direction Z.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, 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 apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily 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 may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

The term "and/or" in this application is merely an association relation describing an associated object, and indicates that three relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In this application, the character "/" generally indicates that the associated object is an or relationship.

In the embodiments of the present application, the same reference numerals denote the same components, and in the interest of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, etc. dimensions of the various components in the embodiments of the present application, as well as the overall thickness, length, width, etc. dimensions of the integrated device, are illustrative only and should not be construed as limiting the present application in any way.

The term "plurality" as used herein refers to more than two (including two).

In the present application, the battery cells may include lithium ion secondary battery cells, lithium ion primary battery cells, lithium sulfur battery cells, sodium lithium ion battery cells, sodium ion battery cells, or magnesium ion battery cells, and the embodiment of the present application is not limited thereto. The battery cells may be cylindrical, flat, rectangular, or otherwise shaped, as well as the embodiments herein are not limited in this regard.

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 by the embodiment of the present application. The battery cells may be cylindrical, flat, rectangular, or otherwise shaped, as well as the embodiments herein are not limited in this regard. The battery cells are generally classified into three types according to the packaging method: the cylindrical battery cell, the square battery cell and the soft package battery cell are not limited thereto.

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, or the like. The battery generally includes a case for enclosing one or more battery cells. The case body can prevent liquid or other foreign matters from affecting the charge or discharge of the battery cells.

The battery cell comprises an electrode assembly and electrolyte, wherein the electrode assembly consists of a positive plate, a negative plate and a separation membrane. The battery cell mainly relies on metal ions to move between the positive and negative electrode plates to operate. The positive plate comprises a positive electrode current collector and a positive electrode active material layer, wherein the positive electrode active material layer is coated on the surface of the positive electrode current collector, the current collector without the positive electrode active material layer protrudes out of the current collector coated with the positive electrode active material layer, and the current collector without the positive electrode active material layer is laminated to serve as a positive electrode 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 electrode sheet comprises a negative electrode current collector and a negative electrode active material layer, wherein the negative electrode active material layer is coated on the surface of the negative electrode current collector, the current collector without the negative electrode active material layer protrudes out of the current collector coated with the negative electrode active material layer, and the current collector without the negative electrode active material layer is laminated to serve as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. The material of the separator may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may be a wound structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The inventors have noted that the electrode assembly is typically electrically connected to an end cap assembly via tabs, which draws electrical energy from the electrode assembly. After further research, it was found that the connection structure between the end cap assembly and the electrode assembly of the battery cell needs to occupy the internal space of the battery cell, reducing the internal capacity of the battery cell and lowering the energy density of the battery cell.

In view of this, the present application provides a technical solution in which an end cap assembly for a battery cell, the end cap assembly including an end cap having an electrode lead-out hole and an electrode terminal; the electrode terminal comprises a connecting part and a terminal main body, and the terminal main body protrudes from the connecting part and is at least partially accommodated in the electrode lead-out hole; the connecting part is provided with a groove. In the scheme, the terminal main body is accommodated in the electrode extraction hole of the end cover, and electric energy is extracted through the terminal main body; through set up the recess at connecting portion, can hold battery cell's electrode terminal's utmost point ear or other parts in the recess, not only alleviateed battery cell's weight, saved battery cell's inner space moreover, improved battery cell's energy density.

The battery cell disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the electric devices. The power supply system with the battery cells, batteries and the like disclosed by the application can be used for forming the power utilization device, so that the stability of the battery performance and the service life of the battery are improved.

The embodiment of the application provides an electricity utilization device using a battery as a power supply, wherein the electricity utilization device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

For convenience of description, the following embodiment will take an electric device according to an embodiment of the present application as an example of the vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the interior of 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 be used as an operating power source of the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

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

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a case 10 and a battery cell 20. In some embodiments, the case 10 may include an upper cover 10a and a lower cover 10b, the upper cover 10a and the lower cover 10b being overlapped with each other, the upper cover 10a and the lower cover 10b together defining an accommodating space for accommodating the battery cell 20. The lower cover 10b may have a hollow structure with one end opened, and the upper cover 10a may have a plate-shaped structure, and the upper cover 10a covers the opening side of the lower cover 10b, so that the upper cover 10a and the lower cover 10b together define an accommodating space; the upper cover 10a and the lower cover 10b may each have a hollow structure with one side opened, and the opening side of the upper cover 10a may be engaged with the opening side of the lower cover 10 b. Of course, the case 10 formed by the upper cover 10a and the lower cover 10b may be of various shapes, such as a cylinder, a rectangular parallelepiped, etc.

Fig. 3 is a schematic structural view of the battery module 400 shown in fig. 2. In the battery 100, the plurality of battery cells 20 may be connected in series, parallel or a series-parallel connection, wherein the series-parallel connection refers to that the plurality of battery cells 20 are connected in series or parallel. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a form that a plurality of battery cells 20 are connected in series or parallel or in series-parallel to form a battery module 400, and a plurality of battery modules 400 are connected in series or parallel or in series-parallel to form a whole and are accommodated in the case 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for making electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 20 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, etc.

Referring to fig. 4, fig. 4 is an exploded view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery. The battery cell 20 includes a case 21, an electrode assembly 22, and other functional components. The end cap 21 refers to a member that is covered at the opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cover 21 may be made of a material (such as an aluminum alloy) with a certain hardness and strength, so that the end cover 21 is not easy to deform when being extruded and collided, so that the battery cell 20 can have higher structural strength, and the safety performance can be improved. The end cap 21 may be provided with functional parts such as electrode terminals 26. The electrode terminals 26 may be used to be electrically connected with the electrode assembly 23 for outputting or inputting electric power of the battery cell 20. In some embodiments, the end cap 21 may also be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. By way of example, the insulation may be plastic, rubber, or the like.

The case 21 is an assembly for forming the internal environment of the battery cell 20, wherein the formed receiving chamber 21a may be used to receive the electrode assembly 22, the electrolyte, and other components. The housing 21 may be of various shapes and various sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 21 may be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 21 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not particularly limited in the embodiment of the present application.

The electrode assembly 22 is a component in which electrochemical reactions occur in the battery cell 20. One or more electrode assemblies 22 may be contained within the housing 21. An insulating film 24 may be provided on the outer surface of the electrode assembly 22 to insulate and protect the battery cells 20 from each other, so that the electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally provided between the positive electrode sheet and the negative electrode sheet. The portions of the positive and negative electrode sheets having active material constitute the main body of the electrode assembly 22, and the portions of the positive and negative electrode sheets having no active material constitute the tabs 232, respectively. The positive electrode tab and the negative electrode tab can be located at one end of the main body together or located at two ends of the main body respectively.

Referring to fig. 5 and 6 in combination, fig. 5 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application; FIG. 6 is a schematic structural view of a flip assembly according to some embodiments of the present application; in a first aspect, the present embodiment provides an end cap assembly 500 for a battery cell 20, the end cap assembly 500 including an end cap 21 and an electrode terminal 26, the end cap 21 having an electrode lead-out hole 21a; the electrode terminal 26 includes a connection part 30 and a terminal body 40, the terminal body 40 protruding from the connection part 30 and being at least partially accommodated in the electrode lead-out hole 21a; the connection portion 30 is provided with a groove 30a.

The grooves 30a may be provided at one side of the connection part 30 facing the electrode assembly 23 of the battery cell 20, at one side of the connection part 30 facing away from the electrode assembly 23, at the side of the connection part 30, or at both the one side of the connection part 30 facing the electrode assembly 23 and the one side facing away from the electrode assembly 23; the shape of the groove 30a may be U-shaped, L-shaped, or ring-shaped, among others. The tab 232 of the electrode assembly 23 may be received in the groove 30a to achieve electrical connection between the tab 232 and the connection part 30, or the tab may be disposed in the groove 30a, or both the tab and the tab 232 may be received in the groove 30a, and the tab 232 may be electrically connected with the connection part 30 through the tab.

In the above-described configuration, the terminal body 40 is accommodated in the electrode extraction hole 21a of the end cap 21, and the electric power is extracted to the outside of the battery cell 20 through the terminal body 40; by providing the grooves 30a in the connection portion 30, the tabs 232 or other components of the battery cell 20 can be accommodated in the grooves 30a, which not only reduces the weight of the battery cell 20, but also saves the internal space of the battery cell 20 and improves the energy density of the battery cell 20.

Referring to fig. 7 to fig. 9 in combination, fig. 7 is a schematic structural diagram of a connection portion according to some embodiments of the present application; FIG. 8 is a schematic view of the connection portion shown in FIG. 6 at another angle; FIG. 9 is an enlarged schematic view of portion A of FIG. 8; in some embodiments, the connection part 30 includes a first connection sub-part 31 and a second connection sub-part 32, the second connection sub-part 32 being connected between the terminal body 40 and the first connection sub-part 31, the thickness H1 of the second connection sub-part 32 being smaller than the thickness H2 of the first connection sub-part 31 to form the groove 30a.

The second connection sub-portion 32 may be disposed at one side or both sides of the first connection sub-portion 31, and the groove 30a is L-shaped; the second connector sub-portion 32 may also be circumferentially disposed about the first connector sub-portion 31, such that the recess 30a is annular. The "second connection sub-portion 32 is connected between the terminal body 40 and the first connection sub-portion 31" means that the projections of the first connection sub-portion 31 onto the terminal body 40 at least partially overlap in the thickness direction X of the end cap 21, "the thickness H1 of the second connection sub-portion 32" means the dimension of the second connection sub-portion 32 in the thickness direction X of the end cap 21, and "the thickness H2 of the first connection sub-portion 31" means the dimension of the first connection sub-portion 31 in the thickness direction X of the end cap 21. The thickness H1 of the second connection sub-portion 32 is smaller than the thickness H2 of the first connection sub-portion 31, which corresponds to thinning the region of the second connection sub-portion 32 of the connection portion 30, forming the groove 30a.

In the above-mentioned scheme, since the thickness of the second connection sub-portion 32 is smaller than that of the first connection sub-portion 31, the terminal body 40 is connected with the thicker first connection sub-portion 31, so that the connection strength between the terminal body 40 and the connection portion 30 can be increased, and the stability of the terminal body 40 can be improved.

In some embodiments, the surface of the connection part 30 facing the electrode assembly 23 of the battery cell 20 is provided with a groove 30a. The grooves 30a may be provided at the side of the connection portion 30, or may be provided at the middle or other regions of the connection portion 30. Since the tab 232 is located at a side of the electrode assembly 23 facing the cap assembly 500, the tab 232 may be directly received in the groove 30a and connected to the second connection sub-portion 32 after being bent, or the tab 232 may be connected to the electrode terminal 26 through the tab after receiving the tab in the groove 30a. The surface of the electrode assembly 23 of the connecting part 30 facing the battery cell 20 is provided with the groove 30a, the tab 232 is not required to bypass the connecting part 30 and then is connected with one side of the connecting part 30 away from the electrode assembly 23, the tab 232 or other parts of the electrode assembly 23 are conveniently accommodated in the groove 30a, the process preparation is convenient, and the production efficiency is improved.

In some embodiments, the surface of the first connector sub-portion 31 facing the end cap 21 and the surface of the second connector sub-portion 32 facing the end cap 21 are flush. That is, the groove 30a is not provided at a side of the connection part 30 facing away from the electrode assembly 23, but is provided at a side of the connection part 30 facing toward the electrode assembly 23.

In the above-mentioned scheme, the surface of the connecting portion 30 facing the end cover 21 is a flat surface, so that the bearing capacity of the connecting portion 30 to the end cover 21 can be improved, and the strength of the end cover assembly 500 can be enhanced.

Optionally, the second connector sub-portion 32 is recessed in the direction of the end cap 21 to form a recess 30a.

In some embodiments, in the thickness direction X of the end cap 21, the thickness of the second connector portion 32 is H1, and the thickness of the first connector portion 31 is H2, 1/5H 2. Ltoreq.H2.ltoreq.H2.ltoreq.4/5H 2. If the thickness of the second connector portion 32 is too small, the structural strength of the second connector portion 32 will be affected; if the thickness of the second connection sub-portion 32 is too large, the accommodating space of the tab 232 or the adapter plate is reduced, the internal space of the battery cell 20 is not greatly changed, and the energy density is limited.

In the above-described scheme, the thickness of the second connector portion 32 is moderate, and not only can the weight and the internal capacity of the battery cell 20 be reduced, but also the strength of the second connector portion 32 can be ensured.

Referring to fig. 10 and 11 in combination, fig. 10 is a schematic structural view of a connecting portion according to other embodiments of the present application; FIG. 11 is a schematic view of another angle of the connecting portion shown in FIG. 10; in some embodiments, the first and second connection sub-portions 31 and 32 are arranged along the first direction Y; at least one end of the second connector portion 32 extends beyond the first connector portion 31 in the second direction Z, and the first direction Y, the second direction Z, and the thickness direction X of the end cap 21 are perpendicular to each other.

Either one end of the second connection sub-portion 32 in the second direction Z may extend beyond the first connection sub-portion 31, or both opposite ends of the second connection sub-portion 32 in the second direction Z extend beyond the first connection sub-portion 31, such that a gap is formed between the first connection sub-portion 31 and the second connection sub-portion 32.

In the above-mentioned scheme, at least one end of the second connection sub-portion 32 exceeds the first connection sub-portion 31, so that the weight of the connection portion 30 can be further reduced, the internal space of the battery cell 20 can be further saved, and the energy density of the battery cell 20 can be improved.

In some embodiments, the number of the second connection sub-portions 32 is two, and the two second connection sub-portions 32 are respectively located at two sides of the first connection sub-portion 31 along the first direction Y; the electrode terminal 26 is provided with a weight-reduction groove 30b, and the weight-reduction groove 30b is located at one side of the first connection sub-portion 31 in the second direction Z and is surrounded by the first connection sub-portion 31 and the two second connection sub-portions 32.

The projection of the weight-reducing groove 30b may not overlap with the projection of the second connector portion 32 in the thickness direction X of the end cap 21, and the weight-reducing groove 30b may be formed by digging a hole in an end portion of the first connector portion 31 in the second direction Z, or the projection of the weight-reducing groove 30b may overlap with the projection portion of one of the second connector portions 32, or the projection portions of the two second connector portions 32, respectively.

In the above-mentioned scheme, the two second connection sub-portions 32 are respectively located at two sides of the first connection sub-portion 31 along the first direction Y, so that one end cap assembly 500 can be connected with two electrode assemblies 23 at the same time, and the energy density of the battery cell 20 is improved. The weight-reducing groove 30b is surrounded by the first connecting sub-portion 31 and the two second connecting sub-portions 32, which not only reduces the weight of the end cover assembly 500 and saves the internal space of the battery cell 20, but also improves the energy density of the battery cell 20 and further improves the connecting space for the parts connected with the second connecting sub-portions 32.

In other embodiments, the weight-reducing groove 30b may be provided in the middle or other regions of the connection portion 30 instead of the end portions of the connection portion 30.

Fig. 12 is a schematic structural view of a connection portion according to still other embodiments of the present application, as shown in fig. 12, in some embodiments, the end cap assembly 500 further includes a sealing member 41 disposed around the terminal body 40, at least a portion of the sealing member 41 is clamped between the end cap 21 and the connection portion 30, and a projection of the weight-reducing groove 30b does not overlap a projection of the sealing member 41 in a thickness direction X of the end cap 21.

The sealing member 41 may be made of a compressible material such as rubber or foam. The sealing member 41 is disposed between the end cap 21 and the connection part 30 in a compressed state, and the sealing member 41 can enhance the sealing effect between the end cap 21 and the electrode terminal 26, reduce the probability of leakage of the battery cell 20, and improve the safety performance of the battery cell 20. In the thickness direction X of the end cap 21, the projection of the weight-reducing groove 30b does not overlap with the projection of the sealing member 41, that is, the sealing member 41 is not disposed at the portion of the connection portion 30 corresponding to the weight-reducing groove 30b, the compression amount of the sealing member 41 can be increased, and the safety performance of the battery cell 20 can be further improved.

FIG. 13 is a schematic view of a connection portion according to further embodiments of the present application; FIG. 14 is a schematic view of another angle of the connecting portion shown in FIG. 13; referring to fig. 13 and 14 in combination, in some embodiments, the connection part 30 includes a tab connection section 321 and a fusing section 322, the fusing section 322 being located between the tab connection section 321 and the terminal body 40, the tab connection section 321 being used to connect the tab 232 of the electrode assembly 23.

The fusing segment 322 is located at a side of the second connection sub-portion 32 near the first connection sub-portion 31, and the through hole 32a is formed at a side of the second connection sub-portion 32 near the first connection sub-portion 31, and a portion of the second connection sub-portion 32 corresponding to the through hole 32a along the second direction Z is the fusing segment 322, because the length L1 of the fusing segment 322 along the second direction Z is smaller than the length L2 of the tab connection segment 321 along the second direction Z, the overcurrent area of the fusing segment 322 is reduced, so that the fusing segment 322 is easy to fuse. It is understood that the through hole 32a may be directly provided at an end of the second connector part 32 along the second direction Z, so as to facilitate the process, and the through hole 32a may be provided at both ends of the second connector part 32 along the second direction Z. Of course, the through holes 32a may be disposed in the middle or other areas of the second connector portion 32 near the first connector portion 31, and the number of the through holes 32a may be one or more.

The tab 232 may be directly welded to the tab connection section 321, or may be connected to the tab connection section 321 through a switching piece.

In the above scheme, through setting up the section of fusing 322 for battery monomer 20 can in time fuse under the outer short operating condition, be difficult for the explosion that fires, improves the security performance of battery monomer 20.

In some embodiments, the end cap assembly 500 further includes a seal member 41 disposed around the terminal body 40, at least a portion of the seal member 41 being sandwiched between the end cap 21 and the connecting portion 30, a projection of the seal member 41 and a projection of the groove 30a not overlapping in the thickness direction X of the end cap 21.

As an example, the recess 30a is provided at the side of the second connector part 32 facing away from the end cap, the projection of the seal 41 not overlapping the projection of the second connector part 32.

The sealing member 41 may be made of a compressible material such as rubber or foam. The sealing member 41 is provided between the end cap 21 and the connection part 30 in a compressed state, so that the sealing effect between the end cap 21 and the electrode terminal 26 can be enhanced, the probability of leakage of the battery cell 20 can be reduced, and the safety performance of the battery cell 20 can be improved.

In the thickness direction X of the end cap 21, the projection of the sealing member 41 does not overlap with the projection of the groove 30a, that is, the sealing member 41 is not disposed at a portion of the connecting portion 30 corresponding to the groove 30a, and the sealing member 41 is compressed by a thicker portion of the connecting portion 30, so that the compression amount of the sealing member 41 can be increased, the probability of leakage of the battery cell 20 can be further reduced, and the safety performance of the battery cell 20 can be improved.

Alternatively, the projection of the seal member 41 falls within the projection range of the first connection sub-portion 31 in the thickness direction X of the end cap 21, and the seal member 41 is clamped between the end cap 21 and the first connection sub-portion 31.

In a second aspect, the present examples provide a battery cell 20 comprising a housing 22, an electrode assembly 23, and an end cap assembly 500 of any of the above embodiments, the housing 22 having an opening; the electrode assembly 23 is accommodated in the case 22; the end cap 21 is used for covering the opening, and the connection part 30 is located inside the battery cell 20.

As shown in fig. 15, fig. 15 is a top view of a battery cell according to some embodiments of the present application; in some embodiments, the electrode assembly 23 has a tab 232, the tab 232 is connected to the connection part 30, and at least a portion of the tab 232 is received in the groove 30a. The tab 232 may be partially accommodated in the groove 30a, or may be completely accommodated in the groove 30a, so that the weight of the battery cell 20 is reduced, the occupied space of the tab 232 is saved, and the energy density of the battery cell 20 is improved.

As shown in fig. 16, fig. 16 is a schematic view of a portion of a battery cell according to some embodiments of the present application. In some embodiments, tab 232 includes a horizontal segment 232b that is directly connected to connection 30. The thickness of the horizontal segment 232b is less than or equal to the depth of the groove 30a in the thickness direction X of the end cap 21.

The electrode assembly 23 includes a main body 231 and a tab 232, and after the tab 232 is bent, the tab 232 includes a vertical section 232a and a horizontal section 232b, the vertical section 232a extends from the main body 231 toward the end cap 21, the horizontal section 232b is bent from the vertical section 232a along a first direction Y and toward a direction approaching the first connection sub-portion 31, and the horizontal section 232b is connected to the second connection sub-portion 32.

In the above-mentioned scheme, the tab 232 is bent to form the horizontal segment 232b, so that the occupied space of the tab 232 can be saved compared with the connection portion 30 of the tab 232 which is not bent. And the horizontal segment 232b is directly connected with the connecting part 30, so that a switching sheet can be omitted, the space is further saved, and the cost is reduced.

In a third aspect, the present examples provide a battery 100 comprising a battery cell 20 of any of the above embodiments.

In a fourth aspect, an embodiment of the present application provides an electrical device, including a battery cell 20 according to any one of the foregoing embodiments, where the battery cell 20 is configured to provide electrical energy.

According to some embodiments of the present application, there is provided an end cap assembly 500 for a battery cell 20, the end cap assembly 500 including an end cap 21 and an electrode terminal 26, the end cap 21 having an electrode lead-out hole 21a; the electrode terminal 26 includes a connection part 30 and a terminal body 40, the terminal body 40 protruding from the connection part 30 and being at least partially accommodated in the electrode lead-out hole 21a; the surface of the connection part 30 facing the electrode assembly 23 of the battery cell 20 is provided with a groove 30a, and the tab 232 is received in the groove 30a and directly connected with the second connection sub-part 32. The connection part 30 includes a first connection sub-part 31 and a second connection sub-part 32, the second connection sub-part 32 being connected between the terminal body 40 and the first connection sub-part 31, the thickness H1 of the second connection sub-part 32 being smaller than the thickness H2 of the first connection sub-part 31 to form the groove 30a.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting thereof; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may be modified or some technical features may be replaced with other technical solutions, which may not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims (15)

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

an end cap having an electrode lead-out hole;

an electrode terminal including a connection portion and a terminal body protruding from the connection portion and at least partially received in the electrode lead-out hole;

the connecting portion is provided with a groove.

2. The end cap assembly of claim 1, wherein the connection portion includes a first connection sub-portion and a second connection sub-portion, the second connection sub-portion being connected between the terminal body and the first connection sub-portion, the second connection sub-portion having a thickness less than a thickness of the first connection sub-portion to form the recess.

3. The end cap assembly according to claim 2, wherein the surface of the connection part facing the electrode assembly of the battery cell is provided with the groove.

4. The end cap assembly of claim 3, wherein a surface of the first connector sub-portion facing the end cap and a surface of the second connector sub-portion facing the end cap are flush.

5. The end cap assembly of any one of claims 2-4, wherein the thickness of the second connector portion is H1 and the thickness of the first connector portion is H2 in the thickness direction of the end cap, 1/5H2 +.h1 +.4/5H 2.

6. The end cap assembly of any one of claims 2-4, wherein the first connector sub-portion and the second connector sub-portion are arranged in a first direction; in the second direction, at least one end of the second connector part exceeds the first connector part, and the first direction, the second direction and the thickness direction of the end cover are perpendicular to each other.

7. The end cap assembly of claim 6, wherein the number of second connector sub-portions is two, the two second connector sub-portions being located on each side of the first connector sub-portion in the first direction; the electrode terminal is provided with a weight-reducing groove which is positioned at one side of the first connecting sub-part along the second direction and is surrounded by the first connecting sub-part and the two second connecting sub-parts.

8. The end cap assembly of claim 7, further comprising a seal disposed around the terminal body, at least a portion of the seal being sandwiched between the end cap and the connection portion, a projection of the weight-reduction groove not overlapping a projection of the seal in a thickness direction of the end cap.

9. The end cap assembly of claim 1 or 2, wherein the connection portion includes a tab connection section and a fusing section, the fusing section being located between the tab connection section and the terminal body, the tab connection section being for connecting a tab of an electrode assembly.

10. The end cap assembly of any one of claims 1-4, further comprising a seal disposed around the terminal body, at least a portion of the seal being sandwiched between the end cap and the connection portion, a projection of the seal not overlapping a projection of the groove in a thickness direction of the end cap.

11. A battery cell, comprising:

a housing having an opening;

an electrode assembly accommodated in the case; and

the end cap assembly of any one of claims 1 to 10, wherein the end cap is configured to cover the opening, and the connecting portion is located inside the battery cell.

12. The battery cell of claim 11, wherein the electrode assembly has a tab connected to the connection portion, and at least a portion of the tab is received in the recess.

13. The battery cell of claim 12, wherein the tab includes a horizontal segment directly connected to the connection portion, the horizontal segment having a thickness less than or equal to a depth of the groove in a thickness direction along the end cap.

14. A battery comprising a cell according to any one of claims 11 to 13.

15. An electrical device comprising a cell according to any one of claims 11 to 13 for providing electrical energy.

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