CN216720087U

CN216720087U - Battery cell, battery and power consumption device

Info

Publication number: CN216720087U
Application number: CN202220243014.6U
Authority: CN
Inventors: 雷育永; 李川; 郭志君; 宋英俊
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2022-06-10
Anticipated expiration: 2032-01-28
Also published as: WO2023142894A1

Abstract

The application provides a battery monomer, battery and power consumption device belongs to battery technical field. The battery cell comprises a shell, an electrode assembly, a first end cover and a second end cover. The inside of casing is formed with and holds the chamber, along predetermineeing the direction, holds the chamber and is formed with first opening and second opening respectively at the both ends of casing. The electrode assembly is accommodated in the accommodating cavity, and a first tab and a second tab are respectively formed at two ends of the electrode assembly in the preset direction. The first end cap is used for covering the first opening and is electrically connected to the first tab. The second end cap is used for covering the second opening and is electrically connected to the second tab. The first opening is larger than the second opening, and the second end cover is configured to cover the second opening after passing through the accommodating cavity from the first opening. The battery monomer of this kind of structure can realize that first end cover and second end cover go into the shell simultaneously to can connect first end cover and second end cover in the casing simultaneously, with shorten the assemble duration, be favorable to improving assembly efficiency.

Description

Battery cell, battery and power consumption device

Technical Field

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

Background

The secondary battery has the outstanding advantages of high energy density, small environmental pollution, large power density, long service life, wide application range, small self-discharge coefficient and the like, is one of the most widely applied batteries in the world nowadays, and is also an important component part for new energy development. The battery monomer of the secondary battery is obtained by assembling an electrode assembly by a positive pole piece, a negative pole piece and a separation film in a winding or laminating mode, then loading the electrode assembly into a shell, covering an end cover, and finally injecting electrolyte. Wherein, free casing of battery and end cover need weld with electrode subassembly's utmost point ear respectively to realize the output and the output of the free electric energy of battery, however, in the battery monomer of this kind of structure, the casing is higher with the welding degree of difficulty of utmost point ear, leads to the free assembly degree of difficulty of battery to be high, and assemble duration is longer, thereby is unfavorable for improving the free production efficiency of battery.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a single battery, a battery and an electric device, which can effectively improve the production efficiency of the single battery.

In a first aspect, an embodiment of the present application provides a battery cell, including a case, an electrode assembly, a first end cap, and a second end cap; an accommodating cavity is formed in the shell, and a first opening and a second opening are formed in the accommodating cavity at two ends of the shell along a preset direction; the electrode assembly is accommodated in the accommodating cavity, and a first tab and a second tab are respectively formed at two ends of the electrode assembly in the preset direction; the first end cover is used for covering the first opening and is electrically connected to the first tab; the second end cover is used for covering the second opening and is electrically connected to the second tab; the first opening is larger than the second opening, and the second end cover is configured to cover the second opening after passing through the accommodating cavity from the first opening.

In the technical scheme, the two ends of the shell in the preset direction are respectively provided with the first opening and the second opening, the first opening is larger than the second opening, so that the second end cover can enter the accommodating cavity from the first opening and cover the second opening from the inside of the accommodating cavity, when the battery cell adopting the structure is produced and assembled, the first end cover and the second end cover can be firstly connected to the first pole lug and the second pole lug of the electrode assembly respectively, then the electrode assembly connected with the first end cover and the second end cover is inserted into the accommodating cavity from the first opening, so that the second end cover can cover the second opening, thereby the function that the first end cover and the second end cover enter the shell simultaneously can be realized, the first end cover and the second end cover can be connected to the two ends of the shell simultaneously during the production and assembly, so as to complete the production and assembly of the battery cell, and then can effectively reduce the free assembly degree of difficulty of battery, and can shorten the assemble duration, be favorable to improving the free production efficiency of battery. In addition, in the battery cell with the structure, the electrode assembly is connected between the first pole lug and the first end cover and between the second pole lug and the second end cover before being assembled into the accommodating cavity of the shell, so that the first pole lug or the second pole lug does not need to be connected with the first end cover and the second end cover after extending out of the shell, the length of the first pole lug and the length of the second pole lug of the electrode assembly are favorably shortened, the production cost of the battery cell can be effectively reduced, and the phenomenon that the first pole lug and the second pole lug are redundant can be relieved.

In some embodiments, the housing includes a connecting portion and a sidewall; the connecting part is an annular structure extending along the circumferential direction of the shell, and the connecting part encloses to form the second opening; the side wall is arranged around the connecting part, one end of the side wall is connected with the connecting part along the preset direction, and the other end of the side wall forms the first opening in a surrounding mode; wherein, along the preset direction, the connecting part is configured to limit the second end cover to be separated from the shell from the second opening to the direction away from the first end cover.

In the above technical scheme, the casing is provided with connecting portion and lateral wall, and the lateral wall encloses to establish at connecting portion for the periphery to form the chamber that holds that is used for holding electrode subassembly. The second opening closes the structure that forms for connecting portion enclose, and connecting portion can restrict the second end cap and break away from the casing to can play certain limiting displacement to the second end cap on the one hand, be favorable to promoting the structural stability between second end cap and the casing, on the other hand can play certain location and guide effect to the second end cap, thereby be convenient for cover the second opening with the second end cap from holding the intracavity, be favorable to assembling the second end cap.

In some embodiments, at least a portion of the second end cap is inserted within the second opening to cover the second opening; along preset direction, the second opening is in the both sides of connecting portion are formed with first sub-opening and second sub-opening respectively, first sub-opening compare in second sub-opening is closer to first end cover, first sub-opening's size is greater than second sub-opening's size, in order to restrict the second end cover is followed the second opening breaks away from to the direction that deviates from first end cover the casing.

In above-mentioned technical scheme, the second opening is formed with first sub-opening and second sub-opening respectively in the both sides of connecting portion, sets up the size through with first sub-opening into being greater than the size of second sub-opening to realized the restriction to the second end cover through this kind of structure, so that the end cover can follow in first sub-opening inserts the second opening, and then be convenient for the second end cover to cover the second opening from holding the intracavity.

In some embodiments, the connecting portion has an inner circumferential wall that encloses the second opening; the inner peripheral wall is provided with a first conical surface, the first conical surface is provided with a large end and a small end which are opposite to each other in the preset direction, and the large end is closer to the first end cover than the small end; and a second conical surface is formed on the outer peripheral side of the second end cover, and the second conical surface and the first conical surface are matched with each other and are abutted against each other.

In the technical scheme, through being formed with first conical surface on the internal perisporium at connecting portion, that is to say, second open-ended pore wall is formed with the structure of first conical surface, and the tip of first conical surface is compared in the tip of first conical surface and is more close to first end cover, so that the second conical surface that the periphery side of making first end cover formed can support and lean on in first conical surface, thereby realized the function that the restriction second end cover breaks away from the casing through this kind of structure, moreover, the steam generator is simple in structure, and convenient to realize, and can also play certain guide effect to the second end cover through the structure of first conical surface and the mutual cooperation of second conical surface, so that guide the second end cover to the second opening in, thereby be favorable to improving the assembly efficiency between second end cover and the casing.

In some embodiments, the second opening includes a first hole section and a second hole section that are sequentially arranged along the preset direction and are mutually communicated, a hole wall of the first hole section is connected to a hole wall of the second hole section, and the hole wall of the first hole section is the first conical surface; the second end cover comprises a first portion and a second portion which are sequentially connected along the preset direction, the second conical surface is formed on the outer peripheral side of the first portion, and at least part of the second portion is accommodated in the second hole section.

In the technical scheme, the second opening is set into the first hole section and the second hole section which are sequentially arranged along the preset direction, and the hole wall of the first hole section is set into the structure of the first conical surface, so that the first conical surface can be formed only by performing a chamfering process on the first hole section during machining, and machining difficulty is reduced, and machining and manufacturing are facilitated. In addition, through forming the periphery side of the first portion with the second end cover with the second circular conical surface that first circular conical surface mutually supported, and hold at least part of second portion in the second hole section, that is to say, a part of second end cover is located first hole section, and another part is located the second hole section to adopt this kind of structure to be favorable to promoting the second end cover and cover the effect of second opening, and be favorable to promoting the assembly stability between second end cover and the connecting portion.

In some embodiments, along the preset direction, the first conical surface extends to a side of the connecting portion facing away from the first end cap, and the small end is formed on a side of the connecting portion facing away from the first end cap.

In the technical scheme, through extending first circular conical surface to one side that connecting portion deviate from first end cover, and form the tip of first circular conical surface on one side that connecting portion deviate from first end cover, that is to say, set up the tip of first circular conical surface into the one side parallel and level that deviates from first end cover with connecting portion, thereby make the whole pore wall of second open-ended be the structure of first circular conical surface, and then make first circular conical surface can play better guide effect to the second end cover on the one hand, be convenient for the second end cover to insert and locate in the second opening, on the other hand is favorable to improving the second end cover and covers in second open-ended structural stability.

In some embodiments, the connecting portion has a step surface against which at least a portion of the second end cap abuts to limit the second end cap from exiting the housing from the second opening in a direction away from the first opening.

In the technical scheme, the step surface is arranged on the connecting part, so that at least part of the second end cover can be abutted against the step surface, the function of limiting the second end cover to be separated from the shell is realized, the structure is simple, and the limiting capacity of the second end cover is favorably improved.

In some embodiments, the second opening includes a third hole section and a fourth hole section that are sequentially arranged along the preset direction and are communicated with each other, a hole wall of the third hole section and a hole wall of the fourth hole section are connected through the step surface, a hole diameter of the third hole section is larger than that of the fourth hole section, and the third hole section is closer to the first end cap than the fourth hole section; the second end cap includes a third portion at least partially received within the third bore section and abutting the step surface, and a fourth portion at least partially received within the fourth bore section.

In the above technical scheme, through setting up the second opening into third hole section and the fourth hole section of arranging in proper order along predetermineeing the direction, and the aperture of third hole section is greater than the aperture of fourth hole section, thereby form the step face that is used for supplying the second end cover to support between the pore wall of third hole section and the pore wall of fourth hole section, and the annular structure of step face for the circumference extension along connecting portion, in order to realize the limit function to the second end cover, and correspond the third part and the fourth part with the second end cover and set up in third hole section and fourth hole section, this kind of structure is favorable to promoting the assembly stability between second end cover and the connecting portion.

In some embodiments, along the preset direction, a side of the second end cap facing away from the first end cap is flush with a side of the connecting portion facing away from the first end cap.

In the technical scheme, one side of deviating from the first end cover through with the second end cover sets up to deviate from one side parallel and level of first end cover with connecting portion, that is to say, the second end cover inserts the terminal surface of locating the second open-ended part and one side parallel and level that connecting portion deviate from the first end cover in the direction of predetermineeing, adopts this kind of structure to be convenient for connect the second end cover on connecting portion, is favorable to guaranteeing connection quality and structural stability between second end cover and the connecting portion, and is convenient for process.

In a second aspect, an embodiment of the present application further provides a battery, including a case and the battery cell described above; the battery unit is accommodated in the box body.

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

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

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

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

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

fig. 4 is an exploded view of a battery cell according to some embodiments of the present disclosure;

FIG. 5 is a schematic structural view of a housing provided in accordance with some embodiments of the present application;

FIG. 6 is a schematic view of the connection of an electrode assembly to an insulating film provided in some embodiments of the present application;

fig. 7 is a cross-sectional view of a battery cell provided in accordance with some embodiments of the present application;

fig. 8 is a partially enlarged view of the battery cell shown in fig. 7 at a;

FIG. 9 is a cross-sectional view of a housing provided in accordance with some embodiments of the present application;

FIG. 10 is an enlarged view of a portion of the housing shown in FIG. 9 at B;

FIG. 11 is a partial cross-sectional view of a second end cap according to some embodiments of the present application;

FIG. 12 is a cross-sectional view of a housing provided in accordance with further embodiments of the present application;

FIG. 13 is an enlarged view of a portion of the housing of FIG. 12 at C;

FIG. 14 is a partial cross-sectional view of a second end cap according to still other embodiments of the present application;

FIG. 15 is a schematic structural view of a housing according to still other embodiments of the present application;

FIG. 16 is an enlarged view of a portion of the housing of FIG. 15 at D;

FIG. 17 is a partial cross-sectional view of a second end cap according to still other embodiments of the present application;

fig. 18 is a partially enlarged view of the battery cell shown in fig. 7 at E.

Icon: 1000-a vehicle; 100-a battery; 10-a box body; 11-a first tank body; 12-a second tank body; 20-a battery cell; 21-a housing; 211-a containment chamber; 212-first opening; 213-a second opening; 2131-a first bore section; 2132-a second bore section; 2133-a third hole segment; 2134-a fourth pore section; 214-a connecting portion; 2141-a first conical surface; 2142-step surface; 215-side wall; 22-an electrode assembly; 221-a first tab; 222-a second tab; 23-a first end cap; 231-a first cover; 2311-an abutment; 2312-a plug-in part; 232-first electrode terminal; 233 — a first insulator; 24-a second end cap; 241-a second cover; 2411-a second conical surface; 2412-first part; 2413-a second part; 2414-third part; 2415-fourth part; 242 — a second electrode terminal; 243-a second insulator; 25-an insulating film; 200-a controller; 300-a motor; x-the preset direction.

Detailed Description

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

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

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

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

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

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

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

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

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

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive pole piece, a negative pole piece and an isolating membrane. 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 includes negative pole mass flow body and negative pole active substance layer, and the negative pole active substance layer coats in the surface of negative pole mass flow body, and the negative pole mass flow body protrusion in the negative pole mass flow body of coating the negative pole active substance layer not coating the negative pole active substance layer, and the negative pole mass flow body of not coating the negative pole active substance layer is as negative pole utmost point ear. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fuse is not fused when a large current is passed, 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 material of the isolation film may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The battery has the outstanding advantages of high energy density, small environmental pollution, large power density, long service life, wide application range, small self-discharge coefficient and the like, and is an important component for the development of new energy. With the continuous development of battery technology, the demand for batteries is increasing, and therefore, the improvement of the production efficiency of batteries is very important.

The inventors have found that improving the production efficiency of the battery requires improving the production efficiency of the battery cell, and after the electrode assembly of the battery cell is mounted in the case, the battery cells are limited by the fact that the difficulty of welding between the tabs of the electrode assembly and the case is high, resulting in long assembly time of the battery cells, in the prior art, the battery cell is usually configured as a housing and two end caps, wherein two ends of the housing are both provided with openings, the two end caps are respectively covered on two ends of the housing, after the electrode lug at one end of the electrode assembly can be welded with one end cover, the end cover is welded at one end of the shell, the electrode lug at the other end of the electrode assembly extends out of the shell and is welded with the electrode terminal of the other end cover, and finally the end cover is welded at the other end of the shell, so that the welding difficulty between the electrode lug of the electrode assembly and the shell is reduced. However, the welding of the two end covers of the battery cell adopting the structure and the shell has a sequence, and the other end cover can be welded with the shell after the welding of the one end cover on the shell is completed, so that the improvement of the production efficiency of the battery cell is not facilitated. In addition, the battery monomer of this kind of structure need extend electrode subassembly's utmost point ear can only weld with the end cover after the casing to lead to electrode subassembly's utmost point ear longer, and then be unfavorable for reducing the free manufacturing cost of battery, and cause utmost point ear to appear redundant phenomenon very easily.

Based on the above consideration, in order to solve the problem of low production efficiency of the battery cell, the inventors have conducted extensive studies to design a battery cell provided with a case, an electrode assembly, a first end cap, and a second end cap. The housing has a containing cavity, and the containing cavity is formed with a first opening and a second opening at two ends of the housing along a preset direction. The electrode assembly is accommodated in the accommodating cavity, and two ends of the electrode assembly in the preset direction are respectively provided with a first tab and a second tab. The first end cover and the second end cover the first opening and the second opening respectively, and the first end cover and the second end cover are electrically connected to a first tab and a second tab of the electrode assembly respectively. The first opening is larger than the second opening, and the second end cover is configured to cover the second opening after passing through the accommodating cavity from the first opening.

In the single battery, the two ends of the shell in the preset direction are respectively provided with the first opening and the second opening, and the first opening is set to be larger than the second opening, so that the second end cover can enter the accommodating cavity from the first opening and cover the second opening from the inside of the accommodating cavity, when the single battery adopting the structure is produced and assembled, the first end cover and the second end cover can be firstly connected to the first pole lug and the second pole lug of the electrode assembly respectively, then the electrode assembly connected with the first end cover and the second end cover is inserted into the accommodating cavity from the first opening, so that the second end cover can cover the second opening, thereby the function of simultaneously putting the first end cover and the second end cover into the shell can be realized, and the first end cover and the second end cover can be welded to the two ends of the shell simultaneously when the single battery is produced and assembled, and then can effectively reduce the free assembly degree of difficulty of battery, and can shorten the assemble duration, be favorable to improving the free production efficiency of battery.

In addition, in the battery monomer of this kind of structure, because electrode subassembly has accomplished before the intracavity is held to the assembly casing between first utmost point ear and the first end cover and between second utmost point ear and the second end cover to need not to extend first utmost point ear or second utmost point ear and link to each other with first end cover and second end cover after the casing, be favorable to shortening the length of electrode subassembly's first utmost point ear and second utmost point ear, and then can effectively reduce battery monomer's manufacturing cost, and can alleviate first utmost point ear and second utmost point ear and appear redundant phenomenon.

The battery cell disclosed in the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but not limited thereto. A power supply system including the battery cell, the battery, and the like disclosed in the present application may be used. Like this, be favorable to reducing the free assembly degree of difficulty of battery to promote the free production efficiency of battery.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric 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 automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

For convenience of description, the following embodiments are described by taking an electric device according to an embodiment of the present application as an example of a vehicle 1000.

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

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

Referring to fig. 2 and 3, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure, and fig. 3 is a schematic structural diagram of a battery cell 20 according to some embodiments of the present disclosure. The battery 100 includes a case 10 and a battery cell 20, and the case 10 is used to accommodate the battery cell 20. Wherein the case 10 is used to provide an assembly space for the battery cells 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first case body 11 and a second case body 12, the first case body 11 and the second case body 12 cover each other, and the first case body 11 and the second case body 12 together define a fitting space for accommodating the battery cell 20. The second box body 12 can be a hollow structure with one open end, the first box body 11 can be a plate-shaped structure, and the first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define an assembly space; the first case body 11 and the second case body 12 may be both hollow structures with one side open, and the open side of the first case body 11 may be covered on the open side of the second case body 12. Of course, the case 10 formed by the first case body 11 and the second case body 12 may be various shapes, for example, a cylindrical body, a rectangular parallelepiped, and the like.

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

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

According to some embodiments of the present disclosure, referring to fig. 3, and please further refer to fig. 4 and 5, fig. 4 is an exploded view of a structure of a battery cell 20 according to some embodiments of the present disclosure, and fig. 5 is a schematic structural view of a housing 21 according to some embodiments of the present disclosure. The embodiment of the application provides a battery cell 20, and the battery cell 20 comprises a shell 21, an electrode assembly 22, a first end cover 23 and a second end cover 24. The housing 21 is formed with an accommodating chamber 211 inside, and the accommodating chamber 211 is formed with a first opening 212 and a second opening 213 at both ends of the housing 21, respectively, along the preset direction X. The electrode assembly 22 is accommodated in the accommodation cavity 211, and both ends of the electrode assembly 22 in the preset direction X are formed with first and second tabs 221 and 222 (positive and negative tabs), respectively. The first end cap 23 is used for covering the first opening 212, and the first end cap 23 is electrically connected to the first tab 221. The second end cap 24 is used for covering the second opening 213, and the second end cap 24 is electrically connected to the second tab 222. The first opening 212 is larger than the second opening 213, and the second end cap 24 is configured to cover the second opening 213 after passing through the accommodating cavity 211 from the first opening 212.

The second end cap 24 is configured to cover the second opening 213 after passing through the accommodating cavity 211 from the first opening 212, that is, the size of the second end cap 24 is smaller than the inner diameters of the first opening 212 and the accommodating cavity 211, so that the second end cap 24 can cover the second opening 213 in the accommodating cavity 211 after entering the accommodating cavity 211 from the first opening 212. When the battery cell 20 is assembled, the first end cap 23 and the second end cap 24 are respectively connected to the first tab 221 and the second tab 222 corresponding to the electrode assembly 22; the electrode assembly 22 with the first end cap 23 and the second end cap 24 connected thereto is inserted into the accommodation cavity 211 from the first opening 212, and the second end cap 24 is inserted into the second opening 213 to cover the second opening 213; the first and second end caps 23 and 24 are then attached to both ends of the case 21, respectively, to complete the assembly of the battery cell 20.

Alternatively, the first end cap 23 and the second end cap 24 may be welded, bonded, or snapped to the housing 21. Illustratively, the first end cap 23 and the second end cap 24 are respectively connected to two ends of the housing 21 by laser welding.

In some embodiments, referring to fig. 6, fig. 6 is a schematic diagram of the connection between the electrode assembly 22 and the insulating film 25 according to some embodiments of the present disclosure. The battery cell 20 may further include an insulating film 25, the insulating film 25 wrapping the outer circumferential sides of the electrode assembly 22, the first end cap 23, and the second end cap 24 in the circumferential direction of the electrode assembly 22. That is, after the first and

second caps

23 and 24 are coupled to the corresponding first and

second tabs

221 and 222 of the electrode assembly 22, respectively, the outer circumferential side of the electrode assembly 22 to which the first and

second caps

23 and 24 are coupled is coated with the insulating film 25. With this structure, on one hand, the electrode assembly 22, the first end cap 23 and the second end cap 24 can be fixed to form an integral body with the electrode assembly 22, the first end cap 23 and the second end cap 24, so as to be inserted into the accommodating cavity 211 of the case 21, and on the other hand, the electrode assembly 22 and the case 21 can be insulated from each other.

For example, the material of the insulating film 25 may be polyimide, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene, or the like.

Referring to fig. 4, in some embodiments, the first end cap 23 may include a first cover 231, a first electrode terminal 232, and a first insulator 233. The first cover 231 covers the first opening 212. The first electrode terminal 232 is mounted on the first cover 231 in an insulated manner, and the first electrode terminal 232 is used to be electrically connected to the first tab 221 of the electrode assembly 22, so as to realize input and output of the positive electrode or the negative electrode of the electrode assembly 22. The first insulating member 233 is disposed on a side of the first cover 231 facing the second opening 213 in the predetermined direction X, and the first insulating member 233 is used for insulating and isolating the first cover 231 and the first tab 221.

The first electrode terminal 232 is mounted on the first cover 231 in an insulated manner, that is, the first electrode terminal 232 is mounted on the first cover 231, but the first electrode terminal 232 and the first cover 231 are not in current conduction.

Illustratively, the first electrode terminal 232 is welded to the first tab 221. The first electrode terminal 232 may be directly welded to the first tab 221, or may be electrically connected to the first tab 221 through other components, for example, after the first tab 221 is welded to the current collecting member, the current collecting member is welded to or abutted against the first electrode terminal 232, so as to achieve the electrical connection between the first tab 221 and the first electrode terminal 232.

Alternatively, referring to fig. 7 and 8, fig. 7 is a cross-sectional view of a battery cell 20 provided in some embodiments of the present application, and fig. 8 is a partial enlarged view of the battery cell 20 shown in fig. 7 at a. The first cover 231 has an abutting portion 2311 and a plugging portion 2312, the abutting portion 2311 abuts against and is connected to one end of the housing 21 away from the second end cap 24 in the preset direction X, the plugging portion 2312 is connected to one side of the abutting portion 2311 facing the second end cap 24 in the preset direction X, and the plugging portion 2312 is plugged into the first opening 212. The first insulating member 233 is mounted to the insertion portion 2312 at a side facing the second end cap 24 in the predetermined direction X.

For example, the material of the first insulating member 233 may include plastic, rubber, plastic, or silicon.

In fig. 4, the second end cap 24 may include a second cover 241, a second electrode terminal 242, and a second insulator 243. The second cover 241 covers the second opening 213 and is connected to an end of the housing 21 away from the first opening 212 in the predetermined direction X. The second electrode terminal 242 is mounted on the second cover 241 in an insulated manner, and the second electrode terminal 242 is used to be electrically connected to the second tab 222 of the electrode assembly 22, so as to realize input and output of the positive electrode or the negative electrode of the electrode assembly 22. The second insulating member 243 is disposed on a side of the second cover 241 facing the first opening 212 in the predetermined direction X, and the second insulating member 243 is used for insulating and isolating the second cover 241 and the second pole piece 222.

The second electrode terminal 242 is mounted on the second cover 241 in an insulated manner, that is, the second electrode terminal 242 is mounted on the second cover 241, but the second electrode terminal 242 and the second cover 241 are not electrically connected.

Illustratively, the second electrode terminal 242 is welded to the second pole ear 222. The second electrode terminal 242 may be directly welded to the second tab 222, or may be electrically connected to the second tab 222 through other components, for example, after the second tab 222 is welded to the current collecting member, the current collecting member is welded to or abutted against the second electrode terminal 242, so as to electrically connect the second tab 222 and the second electrode terminal 242.

For example, the material of the second insulating member 243 may include plastic, rubber, plastic, or silicon.

In some embodiments, the first cover 231 or the second cover 241 may further have a liquid injection hole for injecting the electrolyte into the case 21.

In this embodiment, the housing 21 may also be used to contain an electrolyte, such as an electrolyte. The housing 21 may take a variety of configurations. The material of the housing 21 may be various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

The housing 21 may be in various shapes, such as a cylinder, a rectangular parallelepiped, or the like. The shape of the case 21 may be determined according to the specific shape of the electrode assembly 22. For example, if electrode assembly 22 is of a cylindrical structure, case 21 of a cylindrical structure may be selected; if the electrode assembly 22 has a rectangular parallelepiped structure, the case 21 having a rectangular parallelepiped structure may be used.

In the embodiment of the present application, one or more electrode assemblies 22 may be accommodated in the case 21. Illustratively, in fig. 4, the electrode assemblies 22 are two, and the two electrode assemblies 22 are stacked.

The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. The electrode assembly 22 may include a positive electrode tab, a negative electrode tab, and a separator. The electrode assembly 22 may have a winding type structure 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.

In some embodiments, the battery cell 20 may further include a pressure relief mechanism for relieving pressure inside the battery cell 20 when the internal pressure or temperature of the battery cell 20 reaches a predetermined value.

The pressure release mechanism may be mounted on the first end cap 23 or may be mounted on the second end cap 24. Of course, the battery cell 20 may further include two pressure relief mechanisms, and the first end cap 23 and the second end cap 24 are both provided with the pressure relief mechanisms.

Illustratively, the pressure relief mechanism may be a component such as an explosion-proof valve, an explosion-proof sheet, a gas valve, a pressure relief valve, or a safety valve.

The two ends of the case 21 in the preset direction X are respectively provided with a first opening 212 and a second opening 213, and the first opening 212 is set to be larger than the second opening 213, so that the second end cap 24 can enter the accommodating cavity 211 from the first opening 212, and then the second opening 213 is covered from the inside of the accommodating cavity 211, when the battery cell 20 adopting such a structure is produced and assembled, the first end cap 23 and the second end cap 24 can be firstly connected to the first tab 221 and the second tab 222 of the electrode assembly 22 respectively, and then the electrode assembly 22 connected with the first end cap 23 and the second end cap 24 can be inserted into the accommodating cavity 211 from the first opening 212, so that the second end cap 24 can cover the second opening 213, thereby the function of simultaneously entering the first end cap 23 and the second end cap 24 into the case can be realized, so that the first end cap 23 and the second end cap 24 can be simultaneously connected to the two ends of the case 21 during production and assembly, the production assembly of the single battery 20 is completed, the assembly difficulty of the single battery 20 can be effectively reduced, the assembly time can be shortened, and the production efficiency of the single battery 20 can be improved. In addition, in the battery cell 20 with such a structure, the connection between the first tab 221 and the first end cap 23 and the connection between the second tab 222 and the second end cap 24 are completed before the electrode assembly 22 is assembled into the receiving cavity 211 of the case 21, so that the first tab 221 or the second tab 222 does not need to extend out of the case 21 and then be connected with the first end cap 23 and the second end cap 24, which is beneficial to shortening the lengths of the first tab 221 and the second tab 222 of the electrode assembly 22, thereby effectively reducing the production cost of the battery cell 20 and alleviating the phenomenon of redundancy of the first tab 221 and the second tab 222.

Referring to fig. 5, and with further reference to fig. 9 and 10, according to some embodiments of the present disclosure, fig. 9 is a cross-sectional view of a housing 21 provided in some embodiments of the present disclosure, and fig. 10 is a partial enlarged view of the housing 21 shown in fig. 9 at B. The housing 21 includes a connecting portion 214 and a side wall 215. The connecting portion 214 is an annular structure extending along the circumferential direction of the housing 21, and the connecting portion 214 encloses to form a second opening 213. The side wall 215 is disposed around the connecting portion 214, and along the predetermined direction X, one end of the side wall 215 is connected to the connecting portion 214, and the other end of the side wall 215 encloses the first opening 212. Wherein, along the preset direction X, the connecting portion 214 is configured to limit the second end cap 24 from being separated from the housing 21 from the second opening 213 to the direction away from the first end cap 23.

The side wall 215 surrounds the connecting portion 214, that is, the connecting portion 214 is protruded from an inner circumferential surface of the side wall 215, that is, the side wall 215 covers the connecting portion 214 along a circumferential direction of the connecting portion 214 to form a receiving cavity 211 for receiving the electrode assembly 22, and a first opening 212 is formed at an end of the side wall 215 away from the connecting portion 214 along the predetermined direction X.

Alternatively, the side wall 215 and the connecting portion 214 may be an integral structure or a split structure. When the sidewall 215 and the connecting portion 214 are formed as a single-piece structure, the second opening 213 formed on the connecting portion 214 can also be formed by a stamping or cutting process; when the side wall 215 and the connection portion 214 are of a split structure, the connection portion 214 may be an annular plate-shaped structure extending along the circumferential direction of the housing 21, and the connection portion 214 is welded on the inner circumferential surface of the side wall 215.

Second opening 213 encloses the structure that closes formation for connecting portion 214, and connecting portion 214 can restrict second end cover 24 and break away from casing 21, thereby can play certain limiting displacement to second end cover 24 on the one hand, be favorable to promoting the structural stability between second end cover 24 and the casing 21, on the other hand can play certain location and guide effect to second end cover 24, thereby be convenient for cover second opening 213 from holding the chamber 211 with second end cover 24, be favorable to assembling second end cover 24.

According to some embodiments of the present application, please refer to fig. 10, at least a portion of the second end cap 24 is inserted into the second opening 213 to cover the second opening 213. Along the preset direction X, the second opening 213 is respectively formed with a first sub-opening and a second sub-opening at two sides of the connecting portion 214, the first sub-opening is closer to the first end cap 23 than the second sub-opening, and the size of the first sub-opening is larger than that of the second sub-opening, so as to limit the second end cap 24 to be separated from the housing 21 from the second opening 213 to the direction away from the first end cap 23.

Wherein, along preset direction X, second opening 213 is formed with first sub-opening and second sub-opening respectively in the both sides of connecting portion 214, and first sub-opening is closer to first end cover 23 than second sub-opening, and first sub-opening is greater than the second sub-opening, and the aperture at the both ends of second opening 213 on preset direction X is different promptly, and the aperture of the one end that is close to first end cover 23 is greater than the aperture of the other end.

The second opening 213 is formed with a first sub-opening and a second sub-opening on both sides of the connecting portion 214, and the size of the first sub-opening is set to be larger than that of the second sub-opening, so that the limiting effect on the second end cap 24 is realized through the structure, the end cap can be inserted into the second opening 213 from the first sub-opening, and the second opening 213 is covered from the accommodating cavity 211 by the second end cap 24.

Referring to fig. 10, and with further reference to fig. 11, according to some embodiments of the present application, fig. 11 is a partial cross-sectional view of a second end cap 24 provided in some embodiments of the present application. The connecting portion 214 has an inner peripheral wall that encloses a second opening 213. The inner peripheral wall is formed with a first conical surface 2141, and the first conical surface 2141 has a large end and a small end opposite to each other in the predetermined direction X, and the large end is closer to the first end cap 23 than the small end. A second conical surface 2411 is formed on the outer peripheral side of the second end cap 24, and the second conical surface 2411 and the first conical surface 2141 are mutually matched and abut against each other.

The inner peripheral wall of the connecting portion 214 is formed with a first conical surface 2141, the first conical surface 2141 has a large end and a small end opposite to each other in the predetermined direction X, the large end is closer to the first end cap 23 than the small end, that is, the hole wall of the second opening 213 is formed with a structure of the first conical surface 2141, and the large end of the first conical surface 2141 is closer to the first end cap 23 than the small end of the first conical surface 2141, so that the second conical surface 2411 formed on the outer peripheral side of the second end cap 24 can abut against the first conical surface 2141.

Illustratively, the second conical surface 2411 is provided on the outer peripheral side of the second cover 241 of the second end cap 24.

Through being formed with first conical surface 2141 on the internal perisporium at connecting portion 214 to realized the function that the restriction second end cover 24 breaks away from casing 21 through this kind of structure, moreover, the steam generator is simple in structure, and the realization is convenient, and can also play certain guide effect to second end cover 24 through the structure of first conical surface 2141 and the mutual cooperation of second conical surface 2411, so that guide second end cover 24 to in the second opening 213, thereby be favorable to improving the assembly efficiency between second end cover 24 and the casing 21.

In addition, in the embodiment that the second end cap 24 is connected to the connecting portion 214 of the housing 21 by laser welding, the welding laser is blocked by the second conical surface 2411 of the second end cap 24, so that the phenomenon that the welding laser enters the housing 21 through the gap between the second end cap 24 and the connecting portion 214 can be effectively alleviated, and the risk that the electrode assembly 22 is burned by the welding laser can be reduced.

According to some embodiments of the present disclosure, please continue to refer to fig. 10 and 11, the second opening 213 includes a first hole section 2131 and a second hole section 2132 sequentially arranged along the predetermined direction X and communicated with each other, a hole wall of the first hole section 2131 is connected to a hole wall of the second hole section 2132, and the hole wall of the first hole section 2131 is a first conical surface 2141. The second end cap 24 includes a first portion 2412 and a second portion 2413 connected in series along the predetermined direction X, an outer circumferential side of the first portion 2412 is formed with a second conical surface 2411, and at least a portion of the second portion 2413 is received in the second hole section 2132.

The second cover 241 of the second end cap 24 includes a first portion 2412 and a second portion 2413 connected in sequence, and in the preset direction X, the second portion 2413 is connected to a side of the first portion 2412 facing away from the second insulating member 243, and the second insulating member 243 is connected to a side of the first portion 2412 facing away from the second portion 2413.

Illustratively, the first portion 2412 and the second portion 2413 are a unitary structure.

The second opening 213 is arranged to be the first hole section 2131 and the second hole section 2132 which are sequentially arranged along the preset direction X, and the hole wall of the first hole section 2131 is arranged to be the structure of the first conical surface 2141, so that the first conical surface 2141 can be formed only by performing a chamfering process on the first hole section 2131 during machining, and further, the machining difficulty is favorably reduced, and the machining and the manufacturing are facilitated. In addition, by forming the second conical surface 2411, which is matched with the first conical surface 2141, on the outer peripheral side of the first portion 2412 of the second end cap 24, and accommodating at least part of the second portion 2413 in the second hole section 2132, that is, a part of the second end cap 24 is located in the first hole section 2131, and another part is located in the second hole section 2132, the structure is favorable for improving the effect of covering the second opening 213 by the second end cap 24, and is favorable for improving the assembling stability between the second end cap 24 and the connecting portion 214.

Referring to fig. 12 and 13, fig. 12 is a cross-sectional view of a housing 21 according to some embodiments of the present application, and fig. 13 is a partial enlarged view of the housing 21 shown in fig. 12 at C. Along the preset direction X, the first conical surface 2141 extends to a side of the connecting portion 214 away from the first end cap 23, and forms a small end on a side of the connecting portion 214 away from the first end cap 23.

The first conical surface 2141 extends to a side of the connecting portion 214 departing from the first end cap 23, and a small end of the first conical surface is formed on a side of the connecting portion 214 departing from the first end cap 23, that is, the small end is flush with a side of the connecting portion 214 departing from the first end cap 23, that is, the entire hole wall of the second opening 213 is the first conical surface 2141.

Correspondingly, referring to fig. 14, fig. 14 is a partial cross-sectional view of a second endcap 24 according to still other embodiments of the present application. The second cap body 241 of the second end cap 24 has a second conical surface 2411 on the entire outer peripheral side.

Through extending first circular conical surface 2141 to one side that connecting portion 214 deviates from first end cover 23, and form the tip of first circular conical surface on one side that connecting portion 214 deviates from first end cover 23, thereby make the whole pore wall of second opening 213 be the structure of first circular conical surface 2141, and then make first circular conical surface 2141 can play better guide effect to second end cover 24 on the one hand, be convenient for second end cover 24 inserts and locates in second opening 213, on the other hand is favorable to improving the structural stability that second end cover 24 covers in second opening 213.

In addition, in the embodiment where the second end cap 24 is connected to the connecting portion 214 of the housing 21 by laser welding, such a structure is beneficial to further reduce the phenomenon that laser enters the housing 21 through the gap between the second end cap 24 and the connecting portion 214 when the second end cap 24 and the connecting portion 214 are welded, so as to reduce the risk that the electrode assembly 22 is burned by the welded laser.

According to some embodiments of the present application, referring to fig. 15 and 16, fig. 15 is a schematic structural diagram of a housing 21 provided in some further embodiments of the present application, and fig. 16 is a partial enlarged view of the housing 21 shown in fig. 15 at D. The connecting portion 214 has a stepped surface 2142, and at least a portion of the second end cap 24 abuts against the stepped surface 2142 to limit the second end cap 24 from being removed from the housing 21 from the second opening 213 in a direction away from the first opening 212.

The step surface 2142 is arranged on the connecting portion 214, so that at least part of the second end cover 24 can abut against the step surface 2142, the function of limiting the second end cover 24 to be separated from the housing 21 is achieved, the structure is simple, and the limiting capacity of the second end cover 24 is improved.

With further reference to fig. 16 and with further reference to fig. 17, fig. 17 is a partial cross-sectional view of a second end cap 24 according to still other embodiments of the present application. The second opening 213 includes a third hole segment 2133 and a fourth hole segment 2134 that are sequentially arranged along the predetermined direction X and are mutually communicated, a hole wall of the third hole segment 2133 is connected to a hole wall of the fourth hole segment 2134 through a step surface 2142, an aperture of the third hole segment 2133 is larger than an aperture of the fourth hole segment 2134, and the third hole segment 2133 is closer to the first end cap 23 than the fourth hole segment 2134. The second end cap 24 includes a third portion 2414 and a fourth portion 2415, at least a portion of the third portion 2414 being received within the third bore section 2133 and abutting the step surface 2142, and at least a portion of the fourth portion 2415 being received within the fourth bore section 2134.

The second cover 241 of the second end cap 24 includes a third portion 2414 and a fourth portion 2415 connected in sequence, and in the preset direction X, the fourth portion 2415 is connected to a side of the third portion 2414 facing away from the second insulating member 243, the second insulating member 243 is connected to a side of the third portion 2414 facing away from the fourth portion 2415, and an outer peripheral side of the third portion 2414 protrudes from an outer peripheral side of the fourth portion 2415, so that the third portion 2414 can abut against the step surface 2142.

Illustratively, the third portion 2414 and the fourth portion 2415 are a unitary structure.

By arranging the second opening 213 as the third hole segment 2133 and the fourth hole segment 2134 which are sequentially arranged along the preset direction X, and setting the hole diameter of the third hole segment 2133 to be larger than the hole diameter of the fourth hole segment 2134, a step surface 2142 for the second end cap 24 to abut against is formed between the hole wall of the third hole segment 2133 and the hole wall of the fourth hole segment 2134, the step surface 2142 is an annular structure extending along the circumferential direction of the connecting portion 214, so as to implement a limiting function for the second end cap 24, and the third portion 2414 and the fourth portion 2415 of the second end cap 24 are correspondingly arranged in the third hole segment 2133 and the fourth hole segment 2134, which is beneficial to improving the assembling stability between the second end cap 24 and the connecting portion 214.

In addition, in the embodiment that the second end cap 24 is connected to the connecting portion 214 of the housing 21 by laser welding, the welding laser is blocked by the third portion 2414 of the second end cap 24, so that the phenomenon that the welding laser enters the housing 21 through the gap between the second end cap 24 and the connecting portion 214 can be effectively alleviated, and the risk that the welding laser burns the electrode assembly 22 can be reduced.

Referring to fig. 18, fig. 18 is a partial enlarged view of the battery cell 20 shown in fig. 7 at E, according to some embodiments of the present application. Along the preset direction X, a side of the second end cap 24 facing away from the first end cap 23 is flush with a side of the connecting portion 214 facing away from the first end cap 23.

One side of the second end cap 24 departing from the first end cap 23 is flush with one side of the connecting portion 214 departing from the first end cap 23, that is, an end surface of a portion, inserted into the second opening 213, of the second cover 241 of the second end cap 24 is flush with one side of the connecting portion 214 departing from the first end cap 23 in the preset direction X.

One side of deviating from first end cover 23 through with second end cover 24 sets up to deviate from one side parallel and level of first end cover 23 with connecting portion 214 to adopt this kind of structure to be convenient for connect second end cover 24 on connecting portion 214, be favorable to guaranteeing connection quality and structural stability between second end cover 24 and the connecting portion 214, and be convenient for process.

In addition, in the embodiment where the second end cap 24 is connected to the connecting portion 214 of the housing 21 by welding, this structure facilitates welding the second end cap 24 to the connecting portion 214, which is beneficial to improve the welding quality between the second end cap 24 and the connecting portion 214.

According to some embodiments of the present application, please refer to fig. 18, the connecting portion 214 protrudes from the inner circumferential surface of the sidewall 215 by a dimension of 2mm to 5mm along a radial direction of the second opening 213, and the radial direction of the second opening 213 is perpendicular to the predetermined direction X.

In the above description, the protrusion of the connecting portion 214 from the inner peripheral surface of the sidewall 215 is 2mm to 5mm, that is, the connecting portion 214 extends from the inner peripheral surface of the sidewall 215 to the center of the second opening 213 in the radial direction of the second opening 213, and the extending length is 2mm to 5 mm.

In the embodiment that the second end cap 24 is connected to the connecting portion 214 of the housing 21 by welding, by setting the size of the connecting portion 214 to be 2mm to 5mm protruded from the inner peripheral surface of the sidewall 215, this structure on the one hand facilitates welding the second end cap 24 to the connecting portion 214, and on the other hand can effectively reduce the risk of poor welding quality between the second end cap 24 and the connecting portion 214 due to too small size of the connecting portion 214.

According to some embodiments of the present application, the present application also provides a battery 100 including a case 10 and the battery cell 20 of any of the above aspects. The battery cell 20 is accommodated in the case 10.

According to some embodiments of the present application, the present application further provides an electric device, including the battery 100 of any of the above aspects, and the battery 100 is used for providing electric energy for the electric device.

The powered device may be any of the aforementioned devices or systems that employ battery 100.

According to some embodiments of the present application, referring to fig. 3-11 and 18, the present application provides a battery cell 20 including a case 21, an electrode assembly 22, a first end cap 23 and a second end cap 24. The housing 21 is formed with an accommodating chamber 211 inside, and the accommodating chamber 211 is formed with a first opening 212 and a second opening 213 at two ends of the housing 21 along the preset direction X, respectively, and the first opening 212 is larger than the second opening 213. The electrode assembly 22 is accommodated in the accommodation cavity 211, and a first tab 221 and a second tab 222 are formed at both ends of the electrode assembly 22 in the preset direction X, respectively. The first end cap 23 is used for covering the first opening 212, and the first end cap 23 is electrically connected to the first tab 221. The second end cap 24 is used for covering the second opening 213, and the second end cap 24 is electrically connected to the second tab 222, and the second end cap 24 is configured to cover the second opening 213 after passing through the accommodating cavity 211 from the first opening 212. The casing 21 includes a connecting portion 214 and a side wall 215, the connecting portion 214 is an annular structure extending along a circumferential direction of the casing 21, an inner circumferential wall of the connecting portion 214 is enclosed to form a second opening 213, the second opening 213 includes a first hole section 2131 and a second hole section 2132 which are sequentially arranged along a preset direction X and are communicated with each other, a hole wall of the first hole section 2131 is connected to a hole wall of the second hole section 2132, a first conical surface 2141 is formed on the hole wall of the first hole section 2131, the first conical surface 2141 has a large end and a small end opposite to each other in the preset direction X, and the large end is closer to the first end cap 23 than the small end. The second end cover 24 is inserted into the second opening 213, one side of the second end cover 24 departing from the first end cover 23 is flush with one side of the connecting portion 214 departing from the first end cover 23, a second conical surface 2411 is formed on the outer peripheral side of the second end cover 24, and the second conical surface 2411 and the first conical surface 2141 are mutually matched and mutually abutted. The side wall 215 is disposed around the connecting portion 214, and along the predetermined direction X, one end of the side wall 215 is connected to the connecting portion 214, and the other end of the side wall 215 encloses the first opening 212.

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

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, comprising:

the device comprises a shell, a first connecting piece and a second connecting piece, wherein a containing cavity is formed inside the shell, and a first opening and a second opening are formed in the containing cavity at two ends of the shell respectively along a preset direction;

the electrode assembly is accommodated in the accommodating cavity, and a first tab and a second tab are respectively formed at two ends of the electrode assembly in the preset direction;

the first end cover is used for covering the first opening and is electrically connected to the first tab; and

the second end cover is used for covering the second opening and is electrically connected to the second tab;

the first opening is larger than the second opening, and the second end cover is configured to cover the second opening after passing through the accommodating cavity from the first opening.

2. The battery cell of claim 1, wherein the housing comprises:

the connecting part is an annular structure extending along the circumferential direction of the shell, and the connecting part encloses to form the second opening;

the side wall is arranged around the periphery of the connecting part in a surrounding mode, one end of the side wall is connected with the connecting part along the preset direction, and the other end of the side wall forms the first opening in a surrounding mode;

wherein, along the preset direction, the connecting part is configured to limit the second end cover to be separated from the shell from the second opening to the direction away from the first end cover.

3. The battery cell of claim 2, wherein at least a portion of the second end cap is inserted within the second opening to cover the second opening;

along preset direction, the second opening is in the both sides of connecting portion are formed with first sub-opening and second sub-opening respectively, first sub-opening compare in second sub-opening is closer to first end cover, first sub-opening's size is greater than second sub-opening's size, in order to restrict the second end cover is followed the second opening breaks away from to the direction that deviates from first end cover the casing.

4. The battery cell as recited in claim 3 wherein the connecting portion has an inner peripheral wall that surrounds the second opening;

the inner peripheral wall is provided with a first conical surface, the first conical surface is provided with a large end and a small end which are opposite to each other in the preset direction, and the large end is closer to the first end cover than the small end;

and a second conical surface is formed on the outer peripheral side of the second end cover, and the second conical surface and the first conical surface are matched with each other and are abutted against each other.

5. The battery cell according to claim 4, wherein the second opening comprises a first hole section and a second hole section which are sequentially arranged along the preset direction and are communicated with each other, a hole wall of the first hole section is connected to a hole wall of the second hole section, and the hole wall of the first hole section is the first conical surface;

the second end cover comprises a first portion and a second portion which are sequentially connected along the preset direction, the second conical surface is formed on the outer peripheral side of the first portion, and at least part of the second portion is accommodated in the second hole section.

6. The battery cell as recited in claim 4, wherein the first conical surface extends to a side of the connecting portion facing away from the first end cap along the predetermined direction, and forms the small end at the side of the connecting portion facing away from the first end cap.

7. The battery cell as recited in claim 3 wherein the connecting portion has a stepped surface against which at least a portion of the second end cap abuts to limit the second end cap from exiting the housing from the second opening in a direction away from the first opening.

8. The battery cell of claim 7, wherein the second opening comprises a third hole segment and a fourth hole segment that are sequentially arranged along the predetermined direction and are communicated with each other, a hole wall of the third hole segment and a hole wall of the fourth hole segment are connected through the step surface, a hole diameter of the third hole segment is larger than that of the fourth hole segment, and the third hole segment is closer to the first end cap than the fourth hole segment;

the second end cap includes a third portion at least partially received within the third bore section and abutting the step surface, and a fourth portion at least partially received within the fourth bore section.

9. The battery cell according to any of claims 3-8, wherein a side of the second end cap facing away from the first end cap is flush with a side of the connecting portion facing away from the first end cap in the predetermined direction.

10. A battery, comprising:

a box body; and

the battery cell according to any one of claims 1-9, said battery cell being housed within said case.

11. An electric device, characterized in that it comprises a battery according to claim 10 for providing electric energy.