End cover assembly of battery cell, battery cell, battery and electrical device

Abstract

The present application provides an end cap assembly of a battery cell, a battery cell, a battery and an electrical device, wherein the end cap assembly includes an end cap, an electrode terminal and an insulating member, wherein the end cap is provided with an electrode lead-out hole, wherein at least a portion of the electrode terminal is accommodated in the electrode lead-out hole, wherein at least a portion of the insulating member is accommodated in the electrode lead-out hole to separate the hole wall of the electrode lead-out hole from the electrode terminal, and wherein the insulating member is connected between the electrode terminal and the hole wall of the electrode lead-out hole. Through the above structure, the electrode terminal can be connected to the hole wall of the electrode lead-out hole in its own radial direction through the insulating member, thereby realizing a firm connection between the electrode terminal and the hole wall of the electrode lead-out hole, so that the electrode terminal does not need to form a connection structure with the end cap on both sides of the end cap, thereby reducing the size of the electrode terminal in its own axial direction, thereby reducing the size of the end cap assembly of the battery cell in the axial direction of the electrode terminal, and thus helping to improve the energy density of the battery cell.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an end cover assembly of a battery cell, a battery cell, a battery and an electrical device. Background Art

[0002] Batteries have the advantages of high specific energy and high power density. They are widely used in electronic devices and transportation vehicles, such as mobile phones, laptops, electric vehicles, electric airplanes, electric ships, electric tools, etc.

[0003] As the application scope of batteries continues to expand, people have higher and higher requirements on the energy density of batteries. How to improve the energy density of batteries has always been the focus of technical personnel in this field. Utility Model Content

[0004] In view of the above problems, the present application provides an end cover assembly of a battery cell, a battery cell, a battery and an electrical device. The end cover assembly of the battery cell helps to improve the energy density of the battery cell.

[0005] In a first aspect, some embodiments of the present application provide an end cap assembly of a battery cell, the end cap assembly of the battery cell comprising an end cap, an electrode terminal and an insulating member, the end cap being provided with an electrode lead-out hole, at least a portion of the electrode terminal being accommodated in the electrode lead-out hole, at least a portion of the insulating member being accommodated in the electrode lead-out hole and separating the hole wall of the electrode lead-out hole from the electrode terminal, and the insulating member being connected to the electrode terminal and the hole wall of the electrode lead-out hole.

[0006] Through the above structure, the electrode terminal can be connected to the hole wall of the electrode lead-out hole in its own radial direction through the insulating member, thereby realizing a firm connection between the electrode terminal and the hole wall of the electrode lead-out hole, so that the electrode terminal no longer needs to form a connection structure with the end cover on both sides of the end cover, thereby reducing the size of the electrode terminal in its own axial direction, thereby reducing the size of the end cover assembly of the battery cell in the axial direction of the electrode terminal, which helps to improve the energy density of the battery cell.

[0007] According to the end cap assembly provided in some embodiments of the present application, the end cap assembly includes a connecting structure, and at least one of the end cap and the electrode terminal is connected to the insulating member through the connecting structure, so that the insulating member is firmly connected to the end cap or the electrode terminal.

[0008] According to the end cap assembly provided in some embodiments of the present application, the connection structure is a fusion structure, and the melting points of the insulating member, the electrode terminal and the end cap are all higher than the melting point of the fusion structure, so that in the process of melting the material to form the fusion structure, it is not easy to cause the melting of the insulating member, the electrode terminal and the end cap, and it is not easy to damage the structure of the insulating member, the electrode terminal and the end cap.

[0009] According to the end cap assembly provided in some embodiments of the present application, the welding structure includes solder, which not only facilitates the formation of the welding structure, but also enables the welding structure to provide sufficient connecting force, so that the connection between the end cap and the insulating member and between the electrode terminal and the insulating member is firm.

[0010] According to the end cap assembly provided in some embodiments of the present application, the insulating member is a ceramic structure or a glass structure, which not only makes the insulating member have good insulation performance, but also makes the insulating member have good high temperature resistance.

[0011] According to the end cap assembly provided in some embodiments of the present application, the electrode terminal includes a transition portion and a terminal portion, the transition portion is located on the side of the end cap facing the electrode assembly of the battery cell and is used to connect the terminal portion with the electrode assembly, the terminal portion protrudes from the surface of the transition portion facing the end cap, and at least part of the terminal portion is accommodated in the electrode lead-out hole; the insulating member is sleeved on the outer periphery of the terminal portion.

[0012] According to the end cap assembly provided in some embodiments of the present application, the electrode terminal is an integrally formed structure, so that the electrode terminal can be manufactured synchronously as a whole, which not only facilitates the processing and manufacturing of the electrode terminal, but also makes the overall structure of the electrode terminal have good strength.

[0013] According to the end cap assembly provided in some embodiments of the present application, the end cap assembly also includes an insulating structure, which includes a first part and a second part that are connected to each other, the first part is clamped between the end cap and the electrode terminal, and the second part is located on the side of the end cap facing the electrode assembly of the battery cell, so that the second part can insulate and isolate the end cap from the electrode terminal, and the first part can insulate and isolate the electrode assembly of the battery cell from the end cap.

[0014] According to the end cap assembly provided in some embodiments of the present application, the insulating structure and the electrode terminal are injection molded structures, which is not only beneficial to improving the connection strength between the insulating structure and the electrode terminal, but also beneficial to improving the molding efficiency of the insulating structure.

[0015] According to the end cap assembly provided in some embodiments of the present application, the insulating structure also includes a limiting portion, which is connected to the electrode terminal, so that the insulating structure can be better connected to the electrode terminal, which is beneficial to improving the firmness of the connection between the insulating structure and the electrode terminal.

[0016] According to the end cap assembly provided in some embodiments of the present application, a fuse structure is provided on the transition portion, and the fuse structure is configured to cut off the connection between the electrode assembly and the terminal portion when the temperature exceeds a first threshold value, so that the fuse structure can cut off the connection between the electrode assembly and the terminal portion when an overcurrent occurs at the electrode terminal.

[0017] According to the end cover assembly provided in some embodiments of the present application, the limiting portion covers the fuse structure, and the melting point of the limiting portion is lower than the melting point of the fuse structure, so that when the temperature of the fuse structure exceeds the first threshold and melts, the limiting portion melts, and the molten limiting portion material enters the disconnected fuse structure, thereby keeping the parts on both sides of the fuse structure insulated and isolated, which helps to reduce the possibility of the fuse structure overlapping again to connect the parts on both sides.

[0018] According to the end cap assembly provided in some embodiments of the present application, the transition portion includes a main body area and a transition area which are interconnected, the main body area is connected to the electrode terminal, the transition area is used to connect to the electrode assembly, the fuse structure is arranged in the main body area, and the fuse structure is located between the connection between the main body area and the electrode terminal and the connection between the transition area and the electrode assembly, so that the fusing of the fuse structure can cut off the electrical connection between the electrode assembly and the electrode terminal.

[0019] According to the end cap assembly provided in some embodiments of the present application, the main body area includes a first area and a second area connected to each other, and in the axial direction of the electrode terminal, the thickness of the first area is less than the thickness of the second area, and the first area forms a fuse structure. By setting the thickness of the first area to be less than the thickness of the second area, the temperature at which the first area fuses is lower than the temperature at which the second area fuses, so that the first area can form a fuse structure that is easier to fuse than the second area.

[0020] On the second aspect, some embodiments of the present application also provide a battery cell, which includes a shell, an electrode assembly and an end cover assembly provided by any of the above technical solutions, the shell forms a accommodating space with an opening, the electrode assembly is arranged in the accommodating space, and the end cover of the end cover assembly covers the opening.

[0021] In a third aspect, some embodiments of the present application further provide a battery, which includes the battery cell provided by the aforementioned technical solution.

[0022] In a fourth aspect, some embodiments of the present application further provide an electrical device, which includes a battery provided by the aforementioned technical solution, and the battery is used to provide electrical energy.

[0023] The technical solution provided by the embodiments of the present disclosure brings at least the following beneficial effects:

[0024] Some embodiments of the present application provide an end cap assembly of a battery cell, the end cap assembly comprising an end cap, an electrode terminal and an insulating member, the end cap is provided with an electrode lead-out hole, at least a portion of the electrode terminal is accommodated in the electrode lead-out hole, at least a portion of the insulating member is accommodated in the electrode lead-out hole to separate the hole wall of the electrode lead-out hole from the electrode terminal, and the insulating member is connected between the electrode terminal and the hole wall of the electrode lead-out hole. Through the above structure, the electrode terminal can be connected to the hole wall of the electrode lead-out hole in its own radial direction through the insulating member, so as to achieve a firm connection between the electrode terminal and the hole wall of the electrode lead-out hole, so that the electrode terminal does not need to form a connection structure with the end cap on both sides of the end cap, thereby reducing the size of the electrode terminal in its own axial direction, thereby reducing the size of the end cap assembly of the battery cell in the axial direction of the electrode terminal, which helps to improve the energy density of the battery cell.

[0025] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limitations of the present application. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings.

[0027] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0028] Figure 2 An exploded view of a battery provided in some embodiments of the present application;

[0029] Figure 3 An exploded view of a battery cell provided in some embodiments of the present application;

[0030] Figure 4 A top view of an end cap assembly of a battery cell provided in some embodiments of the present application;

[0031] Figure 5 A disassembled diagram of an end cover assembly of a battery cell provided in some embodiments of the present application;

[0032] Figure 6 for Figure 4 Sectional view at AA in the middle;

[0033] Figure 7 for Figure 6 The enlarged view of point B in the middle;

[0034] Figure 8 for Figure 6 Enlarged view of point C in the middle;

[0035] Fig. 9 A bottom view of an end cap assembly of a battery cell provided in some embodiments of the present application;

[0036] Fig.10 for Fig. 9 Cross-sectional view at DD in the middle.

[0037] In the attached picture:

[0038] 10. Box body; 101. First box body; 102. Second box body; 2. Battery cell; 21. Shell; 22. Electrode assembly; 23. End cap; 231. Electrode lead-out hole; 24. Electrode terminal; 241. Adapter; 2411. Fuse structure; 2412. Main body area; 24121. First area; 24122. Second area; 2413. Adapter area; 242. Terminal part; 2421. Connecting part; 2422. Supporting part; 25. Insulating member; 26. Connecting structure; 27. Insulating structure; 271. First part; 272. Second part; 273. Limiting part; 1000. Vehicle; 100. Battery; 200. Controller; 300. Motor. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0041] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0042] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0044] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0045] In the embodiments of the present application, "parallel" includes not only the absolutely parallel situation, but also the roughly parallel situation conventionally recognized in engineering; at the same time, "perpendicular" also includes not only the absolutely perpendicular situation, but also the roughly perpendicular situation conventionally recognized in engineering. For example, if the angle between two directions is 85°-90°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0046] The term "plurality" used in the present application refers to two or more (including two).

[0047] At present, judging from the development of the market situation, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields.

[0048] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0049] The battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0050] The battery cells may be lithium-ion battery cells, sodium-ion battery cells, sodium-lithium-ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium-sulfur battery cells, magnesium-ion battery cells, nickel-hydrogen battery cells, nickel-cadmium battery cells, lead-acid battery cells, etc.

[0051] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0052] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0053] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0054] As people's requirements for battery energy density become higher and higher, how to improve battery energy density has attracted more and more attention from technicians in this field. In the prior art, in order to firmly connect the electrode terminals in the battery cell to the end cap, the electrode terminals are usually welded to the end cap on both sides of the end cap. Among them, in order to facilitate the welding of the electrode terminals to the end cap, the electrode terminals need to extend out of the electrode lead-out holes by a sufficient size, so that the axial size of the electrode terminals is large, and the battery cell occupies a large space, which is not conducive to improving the energy density of the battery cell.

[0055] In order to improve the energy density of a battery cell, some embodiments of the present application provide an end cap assembly of a battery cell, the end cap assembly comprising an end cap, an electrode terminal and an insulating member, the end cap is provided with an electrode lead-out hole, at least a portion of the electrode terminal is accommodated in the electrode lead-out hole, at least a portion of the insulating member is accommodated in the electrode lead-out hole to separate the hole wall of the electrode lead-out hole from the electrode terminal, and the insulating member is connected between the electrode terminal and the hole wall of the electrode lead-out hole. Through the above structure, the electrode terminal can be connected to the hole wall of the electrode lead-out hole in its own radial direction through the insulating member, so as to achieve a firm connection between the electrode terminal and the hole wall of the electrode lead-out hole, so that the electrode terminal does not need to form a connection structure with the end cap on both sides of the end cap, thereby reducing the size of the electrode terminal in its own axial direction, thereby reducing the size of the end cap assembly of the battery cell in the axial direction of the electrode terminal, which helps to improve the energy density of the battery cell.

[0056] The end cap assembly of the battery cell described in the embodiment of the present application is applicable to the battery cell, the battery and the electrical device using the battery. The battery cell can be used for, but not limited to, batteries, and can also be used for vehicles, aircraft, ships, electronic equipment, electric tools and other products, which can improve the reliability of these products.

[0057] Electrical devices may be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, electric tools, etc. Vehicles may be fuel vehicles, gas vehicles or new energy vehicles, and new energy vehicles may be pure electric vehicles, hybrid vehicles or extended-range vehicles, etc. Spacecraft include aircraft, rockets, space shuttles and spacecrafts, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc.

[0058] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device in an embodiment of the present application.

[0059] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0060] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0061] Please refer to Figure 2 , Figure 2An exploded view of a battery 100 provided for some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 2, and the battery cell 2 is accommodated in the housing 10. Among them, the housing 10 is used to provide a storage space for the battery cell 2. There may be multiple battery cells 2 in the battery 100, and the multiple battery cells 2 may be connected in series, in parallel, or in mixed connection. Mixed connection means that multiple battery cells 2 are both connected in series and in parallel. Multiple battery cells 2 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 2 is accommodated in the housing 10; of course, the battery 100 can also be a battery module formed by first connecting multiple battery cells 2 in series, in parallel, or in mixed connection, and then the multiple battery modules are connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the housing 10.

[0062] The box 10 may include a first box 101 and a second box 102, and the first box 101 and the second box 102 cover each other to define a placement space for accommodating the battery cell 2. The first box 101 and the second box 102 may be in various shapes, such as a cuboid, a cylinder, etc. The first box 101 may be a hollow structure with one side open, and the second box 102 may also be a hollow structure with one side open, and the open side of the second box 102 covers the open side of the first box 101, thereby forming a box 10 with a placement space.

[0063] The battery 100 may further include other structures. For example, the battery 100 may further include a busbar component for realizing electrical connection between the plurality of battery cells 2 .

[0064] Each battery cell 2 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 2 may be cylindrical, flat, rectangular or in other shapes.

[0065] In some embodiments of the present application, Figure 3 As shown, the battery cell 2 includes a housing and an electrode assembly 22, and the electrode assembly 22 is accommodated in the housing. The housing can be a wall structure arranged on the periphery of the battery cell 2, which can form a cavity for accommodating other components of the battery cell 2 such as the electrode assembly 22 and the electrolyte. The electrode assembly 22, as a component accommodated in the housing, is in contact with the electrolyte, and active ions (such as lithium ions) can be conducted between the electrode assembly 22 and the electrolyte.

[0066] The housing includes an end cover assembly and a shell 21 . The shell 21 has an opening, and the end cover assembly covers the opening.

[0067] In some embodiments of the present application, Figures 4 to 6As shown, the end cap assembly of the battery cell 2 includes an end cap 23, an electrode terminal 24 and an insulating member 25. The end cap 23 is provided with an electrode lead-out hole 231, and at least a portion of the electrode terminal 24 is accommodated in the electrode lead-out hole 231; at least a portion of the insulating member 25 is accommodated in the electrode lead-out hole 231 and separates the hole wall of the electrode lead-out hole 231 from the electrode terminal 24, and the insulating member 25 is connected to the electrode terminal 24 and the hole wall of the electrode lead-out hole 231.

[0068] The end cap 23 may be a component in the end cap assembly used to cover the opening of the shell 21, and together with the shell 21, it forms a cavity for accommodating components such as the electrode assembly 22 and the electrolyte. Exemplarily, the end cap 23 may be connected to the opening of the shell 21 by welding, so that the materials of the end cap 23 and the shell 21 are melted together, which is conducive to improving the sealing of the battery cell 2.

[0069] The electrode lead-out hole 231 may be a through-hole structure opened on the end cover 23, which is used to set the electrode terminal 24. The electrode lead-out hole 231 can communicate with the cavity inside the battery cell 2, so that the electrode terminal 24 can be electrically connected to the electrode assembly 22 in the cavity. Exemplarily, the electrode lead-out hole 231 can be formed by machining processes such as milling and drilling, or can be made simultaneously with the end cover 23 by an integral molding process such as stamping.

[0070] The electrode terminal 24 is a component provided on the end cap 23 and can be used to electrically connect to an electrical device or a charging device outside the battery cell 2 so as to charge and discharge the battery cell 2. The electrode terminal 24 can include but is not limited to a columnar structure, and those skilled in the art can configure it according to actual conditions.

[0071] At least part of the electrode terminal 24 is accommodated in the electrode lead-out hole 231, and part of the electrode terminal 24 can be inserted into the electrode lead-out hole 231; part of the electrode terminal 24 extends from the electrode lead-out hole 231 to the side of the end cover 23 away from the electrode assembly 22, so that the power-consuming device or charging device outside the battery cell 2 can be easily connected to the electrode terminal 24; part of the electrode terminal 24 extends from the electrode lead-out hole 231 to the side of the end cover 23 facing the electrode assembly 22, so that the electrode terminal 24 can be easily connected to the pole piece in the electrode assembly 22.

[0072] The insulating member 25 may be a component for insulating and isolating the electrode terminal 24 from the hole wall of the electrode lead-out hole 231, and is made of an insulating material and has good insulating properties. By accommodating at least a portion of the insulating member 25 in the electrode lead-out hole 231, the insulating member 25 can separate the hole wall of the electrode lead-out hole 231 from the electrode terminal 24, so that the electrode terminal 24 is insulated and isolated from the end cap 23. Exemplarily, the insulating member 25 may be provided in an annular shape, at least a portion of the annular insulating member 25 is provided in the electrode lead-out hole 231, and at least a portion of the electrode terminal 24 passes through the annular insulating member 25.

[0073] Connecting the insulating member 25 to the electrode terminal 24 and the hole wall of the electrode lead-out hole 231 may mean that the insulating member 25 is connected to both the electrode terminal 24 and the hole wall of the electrode lead-out hole 231, so that the insulating member 25 can firmly connect the electrode terminal 24 and the hole wall of the electrode lead-out hole 231.

[0074] By accommodating at least a portion of the insulating member 25 in the electrode lead-out hole 231 and connecting the insulating member 25 between the electrode terminal 24 and the hole wall of the electrode lead-out hole 231, the electrode terminal 24 can be connected to the hole wall of the electrode lead-out hole 231 in its own radial direction through the insulating member 25, thereby achieving a firm connection between the electrode terminal 24 and the hole wall of the electrode lead-out hole 231, so that the electrode terminal 24 does not need to form a connection structure 26 with the end cover 23 on both sides of the end cover 23, thereby reducing the size of the electrode terminal 24 in its own axial direction, thereby reducing the size of the end cover assembly of the battery cell 2 in the axial direction of the electrode terminal 24, and helping to improve the energy density of the battery cell 2.

[0075] In some embodiments, Figure 7 and Figure 8 As shown, the end cap assembly includes a connection structure 26 , and at least one of the end cap 23 and the electrode terminal 24 is connected to the insulating member 25 through the connection structure 26 .

[0076] The connection structure 26 may be a structure for connecting the insulating member 25 to the end cap 23 or the electrode terminal 24. Exemplarily, the connection structure 26 may be a combination of protrusions and recesses provided on the insulating member 25 and the end cap 23 or the electrode terminal 24, so that the insulating member 25 and the end cap 23 or the electrode terminal 24 can be firmly connected through the combination of the protrusions and recesses; the connection structure 26 may also be a structure formed after the adhesive or meltable material is solidified, which is located between the insulating member 25 and at least one of the end cap 23 and the electrode terminal 24, so that at least one of the end cap 23 and the electrode terminal 24 is firmly connected to the insulating member 25 through the connection structure 26.

[0077] At least one of the end cap 23 and the electrode terminal 24 is connected to the insulating member 25 via the connecting structure 26. The end cap 23 may be connected to the insulating member 25 via the connecting structure 26, or the electrode terminal 24 may be connected to the insulating member 25 via the connecting structure 26, or both the end cap 23 and the electrode terminal 24 may be connected to the insulating member 25 via the connecting structure 26.

[0078] In some embodiments, the connection structure 26 is a welding structure, and the melting points of the insulating member 25 , the electrode terminal 24 , and the end cap 23 are all higher than the melting point of the welding structure.

[0079] The fusion structure may refer to a structure formed by melting, entering the gap between the end cap 23 and the insulating member 25, and the gap between the electrode terminal 24 and the insulating member 25, and solidifying. By setting the connection structure 26 as a fusion structure, the connection between the end cap 23 and the insulating member 25, and the connection between the electrode terminal 24 and the insulating member 25 are made firm.

[0080] By setting the melting points of the insulating member 25, the electrode terminal 24 and the end cap 23 to be higher than the melting point of the fusion structure, it is not easy to cause the melting of the insulating member 25, the electrode terminal 24 and the end cap 23 during the process of melting the material to form the fusion structure, and it is not easy to damage the structure of the insulating member 25, the electrode terminal 24 and the end cap 23.

[0081] In some embodiments, the fused structure includes a solder.

[0082] The fusion structure includes solder, which means that the fusion structure is formed by the solder in the brazing process entering the gap between the end cover 23 and the insulating member 25 and the gap between the electrode terminal 24 and the insulating member 25 and solidifying. This not only makes it convenient to form the fusion structure, but also enables the fusion structure to provide sufficient connecting force, so that the connection between the end cover 23 and the insulating member 25 and between the electrode terminal 24 and the insulating member 25 is firm.

[0083] In some embodiments, the insulating member 25 is a ceramic structure or a glass structure.

[0084] The insulating member 25 is a ceramic structure or a glass structure, which may mean that the insulating member 25 is made of a ceramic material or a glass material, which not only makes the insulating member 25 have good insulation performance, but also makes the insulating member 25 have good high temperature resistance.

[0085] Exemplarily, the insulating member 25 may also be made of a high temperature resistant insulating material such as a thermosetting resin, so that the insulating member 25 has good high temperature resistance and insulation capabilities.

[0086] In some embodiments, the electrode terminal 24 includes a transition portion 241 and a terminal portion 242, the transition portion 241 is located on the side of the end cover 23 facing the electrode assembly 22 of the battery cell 2 and is used to connect the terminal portion 242 to the electrode assembly 22, the terminal portion 242 protrudes from the surface of the transition portion 241 facing the end cover 23, and at least a portion of the terminal portion 242 is accommodated in the electrode lead-out hole 231; the insulating member 25 is sleeved on the outer periphery of the terminal portion 242.

[0087] The transition part 241 and the terminal part 242 may be different structural parts connected to each other in the electrode terminal 24, wherein the terminal part 242 may refer to a part for passing through the electrode lead-out hole 231, at least a part of the terminal part 242 is accommodated in the electrode lead-out hole 231 and the end thereof extending out of the electrode lead-out hole 231 is used to connect with an electric device or a charging device. By sleeve-arranging the insulating member 25 on the outer periphery of the terminal part 242, the terminal part 242 is insulated and isolated from the hole wall of the electrode lead-out hole 231.

[0088] Exemplarily, the terminal portion 242 may be configured as a columnar structure, so that the terminal portion 242 can be conveniently inserted into the electrode lead-out hole 231 , and both ends of the terminal portion 242 can be located on both sides of the end cover 23 .

[0089] The adapter 241 may refer to a portion for connecting with the pole piece in the electrode assembly 22. The terminal portion 242 is protrudingly arranged on the surface of the adapter 241 facing the end cap 23, so that the adapter 241 is arranged at the end of the terminal portion 242. The adapter 241 is located on the side of the end cap 23 facing the electrode assembly 22 of the battery cell 2, so that the adapter 241 can be directly connected with the pole piece in the electrode assembly 22.

[0090] Exemplarily, the transition portion 241 may be configured as a sheet-like structure, so that the transition portion 241 has a larger area and may be connected to a plurality of electrode sheets in the electrode assembly 22 .

[0091] In some embodiments, two electrode terminals 24 are provided at intervals, one of which is a positive terminal and the other is a negative terminal. For example, the positive terminal can be an aluminum part, that is, made of metal aluminum, the transition part 241 in the negative terminal can be a copper sheet, and the terminal part 242 in the negative terminal can be an aluminum part, so that the electrode terminal 24 has a small resistance.

[0092] In some embodiments, the electrode terminal 24 is an integrally formed structure.

[0093] The electrode terminal 24 is an integrally formed structure, which may mean that the transition portion 241 and the terminal portion 242 are made by an integrally formed processing method such as stamping, so that the electrode terminal 24 can be manufactured as a whole synchronously, which not only makes the processing and manufacturing of the electrode terminal 24 convenient, but also makes the overall structure of the electrode terminal 24 have good strength.

[0094] In some embodiments, the end cap assembly also includes an insulating structure 27, which includes a first part 271 and a second part 272 that are interconnected, the first part 271 is clamped between the end cap 23 and the electrode terminal 24, and the second part 272 is located on the side of the end cap 23 facing the electrode assembly 22 of the battery cell 2.

[0095] The insulating structure 27 may be a structure that plays an insulating role and is disposed on the end cover 23. The insulating structure 27 may be disposed on the surface of the end cover 23 and is used to insulate the end cover 23 from surrounding components.

[0096] The first portion 271 and the second portion 272 may be different structural parts connected to each other on the insulating structure 27, wherein the first portion 271 is sandwiched between the end cap 23 and the electrode terminal 24 to insulate and isolate the end cap 23 from the electrode terminal 24. Exemplarily, the first portion 271 may be disposed on a portion of the hole wall of the electrode lead-out hole 231 of the end cap 23, so that a portion of the electrode terminal 24 is isolated from the hole wall of the electrode lead-out hole 231 by the first portion 271.

[0097] The second portion 272 is disposed on the side of the end cover 23 facing the electrode assembly 22 of the battery cell 2 so that the second portion 272 with insulating properties is disposed between the electrode assembly 22 of the battery cell 2 and the end cover 23 , thereby reducing the possibility of short circuit inside the battery cell 2 .

[0098] In some embodiments, the insulating structure 27 and the electrode terminal 24 are injection molded structures.

[0099] The insulating structure 27 and the electrode terminal 24 are injection-molded structures, which may mean that the insulating structure 27 and the electrode terminal 24 are formed into an integral structure by an injection molding process. Exemplarily, the electrode terminal 24 may be placed in an injection mold as an insert, and the material of the insulating structure 27 is injection-molded on the surface of the electrode terminal 24, so that the insulating structure 27 is formed on the surface of the electrode terminal 24, which is not only conducive to improving the connection strength between the insulating structure 27 and the electrode terminal 24, but also conducive to improving the molding efficiency of the insulating structure 27.

[0100] In some embodiments, Fig. 9 As shown, the insulating structure 27 further includes a limiting portion 273 , and the limiting portion 273 is connected to the electrode terminal 24 .

[0101] The limiting portion 273 may be a structure for limiting the electrode terminal 24 . By connecting the limiting portion 273 to the electrode terminal 24 , the insulating structure 27 can be better connected to the electrode terminal 24 , which is beneficial to improving the firmness of the connection between the insulating structure 27 and the electrode terminal 24 .

[0102] Exemplarily, the limiting portion 273 is connected to the second portion 272, and a limiting gap is formed between the limiting portion 273, the second portion 272 and the first portion 271. The electrode terminal 24 is located in the limiting gap and is connected to the limiting portion 273, the first portion 271 and the second portion 272, so that the electrode terminal 24 is firmly connected to the insulating structure 27.

[0103] In some embodiments, a fuse structure 2411 is provided on the transition portion 241 , and the fuse structure 2411 is configured to cut off the connection between the electrode assembly 22 and the terminal portion 242 when the temperature exceeds a first threshold.

[0104] The fuse structure 2411 may be a structure for cutting off the output of electrical energy from the electrode assembly 22 . The fuse structure 2411 is disposed on the electrode terminal 24 and can cut off the connection between the electrode assembly 22 and the terminal portion 242 when an overcurrent occurs at the electrode terminal 24 .

[0105] By configuring the fuse structure 2411 to cut off the connection between the electrode assembly 22 and the terminal portion 242 when the temperature exceeds the first threshold, the electrode terminal 24 can be melted by the increase in temperature when an overcurrent occurs, thereby cutting off the connection between the electrode assembly 22 and the terminal portion 242 and stopping the electrode assembly 22 from outputting electrical energy to the outside through the electrode terminal 24.

[0106] The first threshold may be the melting point of the fuse structure 2411 , so that the fuse structure 2411 may be fused when the temperature exceeds the first threshold.

[0107] Exemplarily, the melting point of the material at the fuse structure 2411 can be configured as a first threshold value, so that when the temperature to which the fuse structure 2411 is subjected exceeds the first threshold value, it will fuse; the fuse structure 2411 can also be thinned so that the thickness of its material is lower than the thickness of the material at other parts of the transition portion 241, so that the fusing temperature at the fuse structure 2411 is lower than the temperature of other parts of the transition portion 241, so that when the temperature to which the fuse structure 2411 is subjected exceeds the first threshold value, it will fuse.

[0108] In some embodiments, Fig.10 As shown, the limiting portion 273 covers the fuse structure 2411 , and the melting point of the limiting portion 273 is lower than the melting point of the fuse structure 2411 .

[0109] The limiting portion 273 covers the fuse structure 2411, and the limiting portion 273 may cover the fuse structure 2411 on the side of the transition portion 241 away from the second portion 272, so that both sides of the fuse structure 2411 are covered by the insulating structure 27. By setting the melting point of the limiting portion 273 to be lower than the melting point of the fuse structure 2411, when the temperature of the fuse structure 2411 exceeds the first threshold and the fuse structure 2411 is fused, the limiting portion 273 melts, and the melted limiting portion 273 material enters the disconnected fuse structure 2411, so as to keep the parts on both sides of the fuse structure 2411 insulated and isolated, which is conducive to reducing the possibility that the fuse structure 2411 overlaps again to connect the parts on both sides.

[0110] In some embodiments, the transition portion 241 includes a main body area 2412 and a transition area 2413 that are interconnected, the main body area 2412 is connected to the electrode terminal 24, the transition area 2413 is used to connect to the electrode assembly 22, and the fuse structure 2411 is arranged in the main body area 2412, and the fuse structure 2411 is located between the connection between the main body area 2412 and the electrode terminal 24 and the connection between the transition area 2413 and the electrode assembly 22.

[0111] The main body area 2412 and the transition area 2413 may be different areas connected to each other in the transition portion 241. The main body area 2412 may be an area for connecting to the electrode terminal 24, and the transition area 2413 may be an area for connecting to the pole piece in the electrode assembly 22. The transition area 2413 is connected to the main body area 2412, so that the pole piece in the electrode assembly 22 is connected to the electrode terminal 24.

[0112] By setting the fuse structure 2411 in the main body area 2412 and between the connection between the main body area 2412 and the electrode terminal 24 and the connection between the transition area 2413 and the electrode assembly 22, the fuse structure 2411 can be melted to cut off the electrical connection between the electrode assembly 22 and the electrode terminal 24.

[0113] In some embodiments, the main body region 2412 includes a first region 24121 and a second region 24122 that are connected to each other. In the axial direction of the electrode terminal 24 , the thickness of the first region 24121 is less than that of the second region 24122 , and the first region 24121 forms a fuse structure 2411 .

[0114] The first region 24121 and the second region 24122 may be different regions connected to each other in the main region 2412, or two adjacent second regions 24122 may be connected through the first region 24121. By setting the thickness of the first region 24121 to be smaller than the thickness of the second region 24122, the temperature at which the first region 24121 melts is smaller than the temperature at which the second region 24122 melts, so that the first region 24121 can form a fuse structure 2411 that is easier to melt than the second region 24122.

[0115] In some embodiments, there are multiple transition areas 2413, and the multiple transition areas 2413 are arranged at intervals for connecting to different pole pieces in the electrode assembly 22. A fuse structure 2411 is provided between the connection between each transition area 2413 and the electrode assembly 22 and the connection between the main area 2412 and the electrode terminal 24.

[0116] By providing a plurality of transition areas 2413 , and arranging the plurality of transition areas 2413 at intervals and used to connect with different pole pieces in the electrode assembly 22 , the plurality of transition areas 2413 can be connected with pole pieces in different parts of the electrode assembly 22 , respectively.

[0117] By providing a fuse structure 2411 between the connection between each transition area 2413 and the electrode assembly 22 and the connection between the main area 2412 and the electrode terminal 24, the fuse structure 2411 can cut off the connection between the electrode pieces in different parts of the electrode assembly 22 and the electrode terminal 24 in different areas.

[0118] In some embodiments, the electrode terminal 24 includes a connecting portion 2421 and a supporting portion 2422 arranged along its own axial direction. In the axial direction of the electrode terminal 24, the projection of the insulating member 25 is located within the projection range of the supporting portion 2422; the electrode lead-out hole 231 is configured as a stepped hole, and the opening of the large diameter section of the electrode lead-out hole 231 faces the electrode assembly 22 of the battery cell 2. The insulating member 25 is connected between the hole wall of the small diameter section of the electrode lead-out hole 231 and the connecting portion 2421, and at least part of the supporting portion 2422 is located in the large diameter section.

[0119] The connecting portion 2421 and the supporting portion 2422 may be different portions arranged in the axial direction of the electrode terminal 24. The electrode terminal 24 is a stepped structure by arranging the projection of the insulating member 25 in the axial direction of the electrode terminal 24 within the projection range of the supporting portion 2422 in the axial direction of the electrode terminal 24.

[0120] By configuring the electrode lead-out hole 231 as a stepped hole, and arranging the opening of the large diameter section of the electrode lead-out hole 231 toward the electrode assembly 22 of the battery cell 2, the electrode terminal 24 with a stepped structure is inserted into the electrode lead-out hole 231, and at least part of the support portion 2422 is located in the large diameter section of the electrode lead-out hole 231, so that at least part of the support portion 2422 can be abutted against the step surface of the electrode lead-out hole 231, so that when the internal pressure of the battery cell 2 is increased, the support portion 2422 can reduce the abutting force between the adapter 241 and the end cover 23 by abutting against the step surface of the electrode lead-out hole 231, which is beneficial to reducing the deformation of the adapter 241 and improving the reliability of the electrode terminal 24.

[0121] Some embodiments of the present application also provide a battery cell 2, which includes a shell 21, an electrode assembly 22 and an end cover assembly provided by the above technical solution, the shell 21 forms a accommodating space with an opening, the electrode assembly 22 is arranged in the accommodating space, and the end cover 23 of the end cover assembly covers the opening.

[0122] Since the battery cell 2 includes the end cover assembly provided by the above technical solution, the battery cell 2 has a higher energy density.

[0123] Some embodiments of the present application further provide a battery 100, which includes a battery cell 2 provided by the above technical solution, and has a higher energy density.

[0124] Some embodiments of the present application further provide an electric device, which includes the battery 100 provided by the above technical solution, and the battery 100 is used to provide electric energy. The electric device can be any electric device of the above technical solution.

[0125] Some embodiments of the present application provide an end cap assembly of a battery cell 2, the end cap assembly comprising an end cap 23, an electrode terminal 24 and an insulating member 25, the end cap 23 is provided with an electrode lead-out hole 231, at least part of the electrode terminal 24 is accommodated in the electrode lead-out hole 231, the insulating member 25 is sleeved on the electrode terminal 24 accommodated in the electrode lead-out hole 231, and the electrode terminal 24 accommodated in the electrode lead-out hole 231 is connected to the electrode terminal 24 and the hole wall of the electrode lead-out hole 231 through the insulating member 25. The end cap 23 and the electrode terminal 24 are both connected to the insulating member 25 through a connecting structure 26.

[0126] The terminal portion 242 in the electrode terminal 24 protrudes from the surface of the transition portion 241 facing the end cap 23, and the transition portion 241 is located on the side of the end cap 23 facing the electrode assembly 22 of the battery cell 2 and is used to connect the terminal portion 242 to the electrode assembly 22. The insulation structure 27 also includes a stopper 273 covering the fuse structure 2411, and the stopper 273 is connected to the electrode terminal 24.

[0127] In the above structure, the electrode terminal 24 can be connected to the hole wall of the electrode lead-out hole 231 in its own radial direction through the insulating member 25, so as to realize a firm connection between the electrode terminal 24 and the hole wall of the electrode lead-out hole 231, so that the electrode terminal 24 no longer needs to form a connection structure 26 with the end cover 23 on both sides of the end cover 23, thereby reducing the size of the electrode terminal 24 in its own axial direction, thereby reducing the size of the end cover assembly of the battery cell 2 in the axial direction of the electrode terminal 24, which helps to improve the energy density of the battery cell 2.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An end cap assembly of a battery cell, characterized in that: include: An end cap having an electrode lead-out hole; an electrode terminal, at least a portion of which is accommodated in the electrode lead-out hole; An insulating member, at least a portion of which is accommodated in the electrode lead-out hole and separates a hole wall of the electrode lead-out hole from the electrode terminal, and the insulating member is connected to the electrode terminal and the hole wall of the electrode lead-out hole.

2. The end cap assembly according to claim 1, characterized in that: The end cap assembly includes a connection structure through which at least one of the end cap and the electrode terminal is connected to the insulating member.

3. The end cap assembly according to claim 2, characterized in that: The connection structure is a welding structure, and the melting points of the insulating member, the electrode terminal and the end cover are all higher than the melting point of the welding structure.

4. The end cap assembly according to claim 3, characterized in that: The fusion structure includes a solder.

5. The end cap assembly according to claim 1, characterized in that: The insulating member is a ceramic structure or a glass structure.

6. The end cap assembly according to claim 1, characterized in that: The electrode terminal comprises a transition portion and a terminal portion, wherein the transition portion is located on a side of the end cap facing the electrode assembly of the battery cell and is used to connect the terminal portion to the electrode assembly, the terminal portion protrudes from a surface of the transition portion facing the end cap, and at least a portion of the terminal portion is accommodated in the electrode lead-out hole; The insulating member is sleeved on the outer periphery of the terminal portion.

7. The end cap assembly according to claim 6, characterized in that: The electrode terminal is an integrally formed structure.

8. The end cap assembly according to claim 6, characterized in that: It also includes an insulating structure, which includes a first part and a second part connected to each other, the first part is sandwiched between the end cover and the electrode terminal, and the second part is located on a side of the end cover facing the electrode assembly of the battery cell.

9. The end cap assembly according to claim 8, characterized in that: The insulating structure and the electrode terminal are injection molded structures.

10. The end cap assembly according to claim 8, characterized in that: The insulating structure further includes a limiting portion connected to the electrode terminal.

11. The end cap assembly according to claim 10, characterized in that: The transition portion is provided with a fuse structure, and the fuse structure is configured to cut off the connection between the electrode assembly and the terminal portion when the temperature exceeds a first threshold.

12. The end cap assembly according to claim 11, characterized in that The limiting portion covers the fuse structure, and the melting point of the limiting portion is lower than the melting point of the fuse structure.

13. The end cap assembly according to claim 11, characterized in that: The transition portion includes a main body area and a transition area that are connected to each other, the main body area is connected to the electrode terminal, the transition area is used to connect to the electrode assembly, the fuse structure is arranged in the main body area, and the fuse structure is located between the connection between the main body area and the electrode terminal and the connection between the transition area and the electrode assembly.

14. The end cap assembly according to claim 13, characterized in that: The main body region includes a first region and a second region connected to each other. In the axial direction of the electrode terminal, the thickness of the first region is smaller than that of the second region. The first region forms the fuse structure.

15. A battery cell, characterized in that: include: A housing, forming a receiving space with an opening; An electrode assembly is disposed in the accommodation space; The end cap assembly according to any one of claims 1 to 14, wherein the end cap of the end cap assembly covers the opening.

16. A battery, characterized in that: Comprising the battery cell as claimed in claim 15.

17. An electrical device, characterized in that: Comprising a battery as claimed in claim 16, the battery is used to provide electrical energy.

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