Cylindrical battery monomer, battery device and electric equipment

Abstract

The utility model discloses a cylindrical battery monomer, a battery device and electric equipment. The cylindrical battery monomer comprises a shell, an electrode assembly and a current collecting assembly, the electrode assembly is arranged in the shell and comprises a pole piece roll core and a pole lug; the pole piece roll core is provided with a central hole which is through along the axial direction, and the pole lug is connected to the end part of the pole piece roll core along the axial direction. The plurality of tabs are stacked along the radial direction of the pole piece roll core, the plurality of tabs comprise a first tab far away from the central hole, a second tab close to the central hole and a middle-layer tab arranged between the first tab and the second tab, and the first tab is electrically connected with the middle-layer tab. And the current collecting assembly is electrically connected to the shell and is at least electrically connected with the middle-layer tab, so that the electrode assembly is electrically connected with the shell. According to the structure, the electron transmission path between the outer-layer tab and the current collecting plate is shortened, the lithium precipitation of the outer-layer pole piece is reduced, and the over-current capability consistency of the single battery is improved, so that the operation stability of the battery is improved.

Description

Technical Field

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

[0002] Batteries are widely used in various electronic devices, such as mobile phones, laptops, electric vehicles, electric aircraft, electric ships, electric toy cars, electric toy aircraft, electric toy ships, power tools and energy storage systems, etc.

[0003] As the battery load increases, how to improve the flow capacity of battery cells is also one of the research issues in this field. Utility Model Content

[0004] In view of the above problems, the present application provides a cylindrical battery cell, a battery device and an electrical equipment, which shortens the electron transmission path between the outer electrode and the current collecting plate, reduces lithium plating of the outer electrode, improves the consistency of the current capacity of the battery cell, and thus improves the stability of the battery operation.

[0005] In a first aspect, the present application provides a cylindrical battery cell comprising a housing, an electrode assembly, and a current collecting assembly. The electrode assembly is disposed in the housing, and the electrode assembly comprises a pole piece core and a pole lug. The pole piece core has a central hole extending axially therethrough, and the pole lug is connected to the end of the pole piece core along the axial direction. A plurality of pole lugs are stacked radially along the pole piece core, and the plurality of pole lugs include a first pole lug away from the central hole, a second pole lug close to the central hole, and a middle pole lug disposed between the first pole lug and the second pole lug, and the first pole lug is electrically connected to the middle pole lug. The current collecting assembly is electrically connected to the housing, and the current collecting assembly is electrically connected to at least the middle pole lug to electrically connect the electrode assembly and the housing.

[0006] In the technical solution of the embodiment of the present application, a shell is provided to provide a stable and closed internal space for the electrode assembly, which effectively isolates impurities, moisture, etc. in the external environment and improves the stability of the battery cell operation. The pole piece winding method is adopted to form a pole piece core, which reduces the space occupied by the electrode pole piece, improves the utilization rate of the space in the shell, and improves the energy density of the cylindrical battery cell. A plurality of radially stacked pole ears are provided on the pole piece core to enhance the current transmission capacity of the pole piece core. The multi-layer pole ears can disperse the current and reduce the resistance, so that the battery can respond quickly during the charging and discharging process, reduce energy loss, and improve the overall efficiency. In particular, by electrically connecting the first pole ear of the outer layer with the middle pole ear, the electron transmission path between the outer pole ear and the collecting disk is shortened. Not only is the loss in the process of power transmission reduced, but also the risk of lithium plating caused by excessive current density near the outer pole ear is reduced, thereby improving the stability of the cylindrical battery cell operation.

[0007] In some embodiments, multiple tabs are bent toward the center hole and stacked on the end surface of the pole piece core along the axial direction of the pole piece core. In the above structure, bending and folding the multiple pole pieces toward the center hole can reduce the internal space occupied by the tabs, increase the spatial energy density of the cylindrical battery cell, and improve the connection stability between the first tab and the middle tab, increase the connection area between the tab and the current collecting assembly, and improve the connection strength, thereby improving the stability of current transmission and the operational stability of the cylindrical battery cell.

[0008] In some embodiments, the multiple tabs extend in increasing length along the axial direction of the pole piece core, from the center hole of the pole piece core toward the edge of the pole piece core. In the above structure, extending the length of the outer ring tab can better utilize the space within the housing and improve the stability of the connection between the outer ring tab and the middle ring tab.

[0009] In some embodiments, the current collecting assembly includes a collecting plate and a collecting connector. The collecting plate is welded to the tab, one end of the collecting connector is connected to the circumference of the collecting plate, and the other end of the collecting connector is connected to the outer shell to electrically connect the collecting plate to the outer shell. In the above structure, the provision of the collecting plate increases the contact area between the current collecting assembly and the tab, improving the strength and stability of the connection. The collecting connector is connected to the edge of the collecting plate, which can reduce the occupied space and improve the energy density of the cylindrical battery cell.

[0010] In some embodiments, the diameter of the current collecting disk is smaller than the diameter of the pole piece core, and the edge of the current collecting disk is spaced apart from at least a portion of the first pole tab. In the above structure, the area of the current collecting disk is smaller than the area of the end surface of the pole piece core, reducing the space occupied by the current collecting disk. A gap is also provided between the edge of the current collecting disk and at least a portion of the first pole tab, providing space for the installation of structures such as an insulating sheet.

[0011] In some embodiments, the electrode assembly includes a first connecting portion connected between the current collecting disk and the middle tab. The first connecting portion extends along the edge of the electrode core toward the center hole and connects the first tab to the middle tab, thereby electrically connecting the first tab and the current collecting disk. In the above structure, by providing the first connecting portion to sequentially connect the first tab, the middle tab, and the current collecting disk, the electron transmission path between the first tab and the current collecting disk is shortened, the current flow capacity of each part of the electrode assembly is improved, and thus the operating stability of the cylindrical battery cell is improved.

[0012] In some embodiments, the first connecting portion bends and extends along the pole piece core toward the center hole. In the above structure, the length of the first connecting portion is extended, the connection strength between the first tab and the middle tab is enhanced, the contact area between the middle tab and the current collecting plate is increased, and the connection strength is improved.

[0013] In some embodiments, the first connecting portion is formed by welding the middle tab and the first tab. In the above structure, the first connecting portion is formed by melting the materials of the middle tab and the first tab by high-temperature heating and then cooling, which facilitates manufacturing and does not require additional welding materials, thereby improving manufacturing efficiency and reducing production costs.

[0014] In some embodiments, there are multiple first connection portions, each of which is spaced apart along the circumference of the electrode core. In the above structure, increasing the number of first connection portions increases the contact area between the first connection portions and the current collecting disk and the electrode tab, thereby increasing the number of connection points, improving the connection stability between the electrode tab and the current collecting disk, and enhancing the consistency of the current flow capacity of each part of the electrode assembly.

[0015] In some embodiments, the electrode assembly includes a second connecting portion, a first tab of the second connecting portion, and a middle tab. Multiple second connecting portions are arranged along the circumference of the central hole and arranged sequentially along an annular path. In the above structure, the provision of the second connecting portion forms a flow path between the interconnected tabs, allowing tabs on different layers to form a current output flow channel with the collector plate welding point through the flow path, thereby improving the consistency of the flow capacity of the electrode assembly.

[0016] In some embodiments, there are multiple second connection portions, each of which is spaced apart radially along the electrode core. In the above structure, increasing the number of second connection portions increases the contact area between the second connection portions and the current collecting disk and the electrode tab, thereby increasing the number of connection points, improving the connection stability between the electrode tab and the current collecting disk, and enhancing the consistency of the current flow capacity throughout the electrode assembly.

[0017] In some embodiments, the second connecting portion includes a first welding ring, which is connected between the first pole ear and the middle pole ear. The first welding ring includes a plurality of first welding blocks spaced apart along an annular path, and the first welding blocks are formed by welding the first pole ear and the middle pole ear. In the above structure, a first welding ring is provided to electrically connect the outer first pole ear with the middle pole ear to form a current path of the first pole ear-middle pole ear-current collecting disk, thereby shortening the electron transmission path between the outer ring pole ear and the current collecting disk, and improving the consistency of the current flow capacity of various parts of the electrode assembly.

[0018] In some embodiments, the cylindrical battery cell further includes an insulating member disposed between the electrode core and the outer casing, wrapping the electrode core. The second connecting portion is spaced apart from the insulating member. This structure improves the insulation performance between the electrode assembly and the outer casing. The spacing between the second connecting portion and the insulating member reduces damage to the insulating member during the manufacturing process, thereby improving the insulation effect.

[0019] In a second aspect, the present application provides a battery comprising the cylindrical battery cell in the above embodiment.

[0020] In a third aspect, the present application provides an electrical device, which includes the battery in the above embodiment, and the battery is used to provide electrical energy.

[0021] 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

[0022] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0023] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0024] Figure 2 A schematic diagram of the exploded structure of a battery provided in some embodiments of the present application;

[0025] Figure 3 A schematic structural diagram of a cylindrical battery cell provided in some embodiments of the present application;

[0026] Figure 4 A schematic diagram of the exploded structure of a cylindrical battery cell provided in some embodiments of the present application;

[0027] Figure 5 A schematic diagram of the structure of an electrode assembly provided in some embodiments of the present application;

[0028] Figure 6 A schematic diagram of a partial structure of a cylindrical battery cell provided in some embodiments of the present application;

[0029] Figure 7 for Figure 6 Schematic diagram of the cross-sectional structure at AA in the middle;

[0030] Figure 8 for Figure 7 A schematic diagram of the enlarged structure of an embodiment at B in FIG.

[0031] Figure 9 This is a schematic structural diagram of the first connecting portion of some embodiments of the present application;

[0032] Figure 10 Schematic diagram of the structure of the first connecting portion of some other embodiments of the present application;

[0033] Figure 11 for Figure 7 A schematic diagram of the enlarged structure of another embodiment at B;

[0034] Figure 12 This is a schematic structural diagram of the second connecting portion of some embodiments of the present application.

[0035] DETAILED DESCRIPTION OF THE REFERENCE NUMERALS

[0036] 1. Vehicle; 2. Battery; 10. Electrode assembly; 101. Pole sheet core; 102. Tab; 103. Center hole; 104. First tab; 105. Second tab; 106. Middle tab; 20. Shell; 25. Electrode terminal; 30. End cap; 40. Outer shell; 50. Current collecting assembly; 501. Current collecting disk; 502. Current collecting connection; 503. First connection; 504. Second connection; 505. First welding ring; 506. Second welding ring; 507. First welding block; 508. Second welding block; 509. Third welding block; 510. Third welding ring; 3. Controller; 4. Motor; 5. Case; 51. First case portion; 52. Second case portion; 53. Accommodation space; X, axial direction; 7. Cylindrical battery cell. DETAILED DESCRIPTION

[0037] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0039] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0040] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0042] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0043] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0044] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0045] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0046] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0047] At present, in cylindrical battery cells, a current collecting plate is usually provided to electrically connect the electrode assembly with the pole on the outer shell. The current collecting plate is welded to the pole tab, and the current collecting plate is electrically connected to the pole. When welding the pole tab, the current collecting plate is usually only connected to the inner ring pole tab of the electrode assembly through a weld. The weld point forms an overcurrent between the electrode assembly and the current collecting plate. The current of the outer ring pole tab needs to pass through the middle ring pole tab to reach the weld point to form an overcurrent. When the battery cell is charged at a high rate, the electron transmission path of the outer ring pole tab is long and the impedance is large. Electrons and lithium ions are concentrated near the outer ring pole tab. When the current density exceeds the lithium plating window, lithium plating occurs, causing safety problems of the battery cell.

[0048] Based on the above problems, an embodiment of the present application provides a cylindrical battery cell, in which an outer shell is provided to provide a stable and closed internal space for the electrode assembly, effectively isolating impurities, moisture, etc. in the external environment, thereby improving the stability of the battery cell operation. The pole piece winding method is adopted to form a pole piece core, which reduces the space occupied by the electrode pole piece, improves the utilization rate of the space in the outer shell, and improves the energy density of the cylindrical battery cell. A plurality of radially stacked pole ears are provided on the pole piece core to enhance the current transmission capacity of the pole piece core. The multi-layer pole ears can disperse the current and reduce the resistance, so that the battery can respond quickly during the charging and discharging process, reduce energy loss, and improve the overall efficiency. In particular, by electrically connecting the first pole ear of the outer layer with the middle pole ear, the electron transmission path between the outer pole ear and the current collecting disk is shortened. Not only is the loss during the power transmission process reduced, but also the risk of lithium plating caused by excessive current density near the outer pole ear is reduced, thereby improving the stability of the cylindrical battery cell operation.

[0049] The battery of the present application is described in detail below.

[0050] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0051] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is a battery module formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells using cable ties.

[0052] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0053] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0054] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0055] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0056] Battery cells may include but are not limited to 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.

[0057] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc. There is no special limitation in this application.

[0058] 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.

[0059] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0060] The battery disclosed in the embodiments of the present application can be used in electrical devices that use the battery as a power source or various energy storage systems that use the battery as an energy storage element. The electrical device can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, and the like. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like, and the spacecraft can include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0061] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0062] Figure 1A schematic structural diagram of a vehicle provided for some embodiments of the present application.

[0063] like Figure 1 As shown, a battery 2 is provided inside the vehicle 1, and the battery 2 can be provided at the bottom, head, or tail of the vehicle 1. The battery 2 can be used to power the vehicle 1, for example, the battery 2 can be used as an operating power source for the vehicle 1.

[0064] The vehicle 1 may further include a controller 3 and a motor 4 . The controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of the vehicle 1 during startup, navigation, and driving.

[0065] In some embodiments of the present application, the battery 2 can not only serve as the operating power source of the vehicle 1, but also serve as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0066] Figure 2 Schematic diagram of the exploded structure of the battery provided in some embodiments of the present application.

[0067] The housing 5 is used to accommodate cylindrical battery cells 7 and can have various structures. In some embodiments, the housing 5 can include a first housing portion 51 and a second housing portion 52. The first housing portion 51 and the second housing portion 52 overlap each other and together define a storage space 53 for accommodating the cylindrical battery cells 7. The second housing portion 52 can be a hollow structure with one end open. The first housing portion 51 is a plate-like structure, and the first housing portion 51 overlaps the open side of the second housing portion 52 to form the housing 5 with the storage space 53. The first housing portion 51 and the second housing portion 52 can also each be a hollow structure with one end open. The open side of the first housing portion 51 overlaps the open side of the second housing portion 52 to form the housing 5 with the storage space 53. Of course, the first housing portion 51 and the second housing portion 52 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0068] In order to improve the sealing performance after the first box body 51 and the second box body 52 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 51 and the second box body 52 .

[0069] Assuming that the first box portion 51 covers the top of the second box portion 52 , the first box portion 51 can also be referred to as an upper box cover, and the second box portion 52 can also be referred to as a lower box.

[0070] In the battery 2, there can be one or more cylindrical battery cells 7. If there are multiple cylindrical battery cells 7, the multiple cylindrical battery cells 7 can be connected in series, in parallel, or in a hybrid connection. Hybrid connection refers to the multiple cylindrical battery cells 7 being connected both in series and in parallel. The multiple cylindrical battery cells 7 can be directly connected in series, in parallel, or in a hybrid connection, and then the entirety of the multiple cylindrical battery cells 7 is housed in the housing 5. Of course, multiple battery cells can also be first connected in series, in parallel, or in a hybrid connection to form a battery module, and then the multiple battery modules are further connected in series, in parallel, or in a hybrid connection to form a single unit, which is then housed in the housing 5.

[0071] In some optional embodiments, the cylindrical battery cells 7 may also be directly accommodated in the box body 5 to reduce the number of connecting components or supporting components required to form the battery module and improve the energy density of the battery 2 .

[0072] For example, the cylindrical battery cell 7 may be the smallest unit constituting the battery 2 .

[0073] Figure 3 A schematic structural diagram of a battery cell provided in some embodiments of the present application.

[0074] like Figure 3 As shown, in some embodiments, the cylindrical battery cell 7 includes a housing 40 and an electrode assembly 10 accommodated in the housing 40 .

[0075] The electrode assembly 10 includes a positive electrode and a negative electrode. During the charge and discharge process of the cylindrical battery cell 7, active ions (e.g., lithium ions) are intercalated and released between the positive and negative electrodes. Optionally, the electrode assembly 10 also includes a separator disposed between the positive and negative electrodes. The separator can reduce the risk of short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0076] The housing 40 is used to encapsulate the electrode assembly 10 and the electrolyte and other components. The housing 40 can be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing 40), or an aluminum-plastic film.

[0077] In some embodiments, the housing 40 includes a shell 20 and an end cover 30 . The shell 20 has an opening, and the end cover 30 is used to cover the opening.

[0078] The housing 20 is a component used to cooperate with the end cap 30 to form an internal cavity of the cylindrical battery cell 7. The formed internal cavity can be used to accommodate the electrode assembly 10, electrolyte and other components.

[0079] The housing 20 and the end cap 30 may be separate components. For example, an opening may be provided on the housing 20 , and the end cap 30 may be placed over the opening to form an internal cavity of the cylindrical battery cell 7 .

[0080] The end cover 30 is connected to the housing 20 by welding, bonding, clamping or other methods.

[0081] In some embodiments, the cylindrical battery cell 7 further includes an electrolyte contained in the housing 40. The electrolyte serves to conduct ions between the positive and negative electrodes and can be in liquid, gel, or solid form.

[0082] In some embodiments, the cylindrical battery cell 7 includes an electrode terminal 25 . The electrode terminal 25 is electrically connected to the electrode assembly 10 to output or input electrical energy from the cylindrical battery cell 7 .

[0083] In some embodiments, the cylindrical battery cell 7 includes a pressure relief mechanism, which is configured to rupture when the internal pressure of the cylindrical battery cell 7 exceeds a threshold value to relieve the internal pressure of the cylindrical battery cell 7 .

[0084] Please refer to Figures 2 to 6 ,in, Figure 4 This is a schematic diagram of the exploded structure of a cylindrical battery cell provided in some embodiments of the present application. Figure 5 This is a schematic diagram of the structure of the electrode assembly provided in some embodiments of the present application. Figure 6 Schematic diagram of the partial structure of a cylindrical battery cell provided in some embodiments of the present application.

[0085] As shown in the figure, the cylindrical battery cell 7 includes a shell 40, an electrode assembly 10 and a current collecting assembly. The electrode assembly 10 is arranged in the shell 40, and the electrode assembly 10 includes a pole piece core 101 and a pole lug 102. The pole piece core 101 has a central hole 103 extending along the axial direction X, and the pole lug 102 is connected to the end of the pole piece core 101 along the axial direction X. A plurality of pole lugs 102 are stacked along the radial direction of the pole piece core 101, and the plurality of pole lugs 102 include a first pole lug 104 away from the central hole 103, a second pole lug 105 close to the central hole 103, and a middle pole lug 106 arranged between the first pole lug 104 and the second pole lug 105, and the first pole lug 104 is electrically connected to the middle pole lug 106. The current collecting assembly is electrically connected to the shell 40, and the current collecting assembly is electrically connected to at least the middle pole lug 106 to electrically connect the electrode assembly 10 and the shell 40.

[0086] The electrode core 101 is formed by winding the electrode sheet along the axial direction X. The central hole 103 is a naturally formed through-hole within the electrode core 101 after it is formed. The tabs 102 are located at the ends of the electrode core 101 along the axial direction X, with the positive tab at the first end and the negative tab at the second end. The housing 40 is provided with electrode terminals 25, and the current collector assembly is connected to the electrode terminals 25 to transmit electrical energy from the electrode assembly 10.

[0087] Optionally, an insulating component is provided between the outer shell 40 and the electrode assembly 10 , and the insulating component is used to achieve insulation between the electrode assembly 10 and the outer shell 40 , thereby reducing the risk of short circuit and leakage of the outer shell 40 .

[0088] The first pole tab 104 is the outermost pole tab 102, or the first pole tab 104 is the N pole tabs 102 closest to the outer side of the end face of the pole piece core 101, where 3≤N≤5. At least a portion of one or more first pole tabs 104 is spaced apart from the current collecting assembly, that is, a gap exists between at least a portion of the first pole tab 104 and the current collecting assembly, preventing direct welding connection. The orthographic projection of the current collecting assembly on the end face of the pole piece core 101 completely covers the middle pole tab 106, allowing direct contact between the middle pole tab 106 and the current collecting assembly, facilitating welding or other connections.

[0089] In the technical solution of the embodiment of the present application, a housing 40 is provided to provide a stable and enclosed internal space for the electrode assembly 10, effectively isolating impurities, moisture, etc. from the external environment, thereby improving the operational stability of the cylindrical battery cell 7. The pole piece winding method is used to form the pole piece core 101, which reduces the space occupied by the electrode pieces, improves the utilization rate of the space within the housing 40, and increases the energy density of the cylindrical battery cell 7. A plurality of radially stacked tabs 102 are provided on the pole piece core 101 to enhance the current transmission capacity of the pole piece core 101. The multi-layered tabs 102 can disperse the current and reduce resistance, allowing the battery 2 to respond quickly during the charge and discharge process, reducing energy loss and improving overall efficiency. In particular, by first electrically connecting the outer first tab 104 to the middle tab 106, the electron transmission path between the outer tab and the current collecting disk is shortened, and then the middle tab is connected to the current collecting assembly. This forms a current path from the outer tab to the middle tab to the current collecting assembly. This not only reduces the loss during power transmission, but also reduces the risk of lithium deposition due to excessive current density near the outer tabs, thereby improving the operational stability of the cylindrical battery cell 7.

[0090] In some embodiments of the present application, multiple pole tabs 102 are bent toward the center hole 103 and stacked on the end surface of the pole tab core 101 along the axial direction X of the pole tab core 101. In the above structure, bending and folding the multiple pole tabs toward the center hole 103 can reduce the internal space of the housing 40 occupied by the pole tabs 102, thereby increasing the spatial energy density of the cylindrical battery cell 7, and improving the connection stability between the first pole tab 104 and the middle pole tab 106. The connection area between the pole tab 102 and the current collecting assembly is increased to improve the connection strength, thereby improving the stability of current transmission and the operating stability of the cylindrical battery cell 7.

[0091] like Figure 5As shown, in some embodiments of the present application, the extension lengths of the plurality of tabs 102 along the axial direction X of the pole piece core 101 increase in sequence from the central hole 103 of the pole piece core 101 toward the edge of the pole piece core 101. In the above structure, extending the length of the outer ring tabs can better utilize the space within the housing 40 and improve the stability of the connection between the outer ring tabs and the middle ring tabs.

[0092] like Figure 4 As shown, in some embodiments of the present application, the current collecting assembly 50 includes a current collecting disc 501 and a current collecting connection portion 502. The current collecting disc 501 is welded to the tab 102, one end of the current collecting connection portion 502 is connected to the circumference of the current collecting disc 501, and the other end of the current collecting connection portion 502 is connected to the housing 40 to electrically connect the current collecting disc 501 to the housing 40. In the above structure, the provision of the current collecting disc 501 increases the contact area between the current collecting assembly 50 and the tab 102, improves the strength and stability of the connection, and the current collecting connection portion 502 is connected to the edge of the current collecting disc 501, which can reduce the occupied space and improve the energy density of the cylindrical battery cell 7.

[0093] like Figure 6 As shown, in some embodiments of the present application, the diameter of the current collecting disk 501 is smaller than the diameter of the pole piece core 101, and the edge of the current collecting disk 501 is spaced apart from at least a portion of the first pole tab 104. In the above structure, the area of the current collecting disk 501 is smaller than the area of the end surface of the pole piece core 101, reducing the space occupied by the current collecting disk 501, and a gap is provided between the edge of the current collecting disk 501 and at least a portion of the first pole tab 104, providing space for the installation of structures such as an insulating sheet.

[0094] Please refer to Figures 7 to 9 In some embodiments of the present application, the electrode assembly 10 includes a first connecting portion 503, which is connected between the first pole tab 104 and the middle pole tab 106. The first connecting portion 503 extends along the edge of the pole sheet core 101 toward the center hole 103 and connects the first pole tab 104 with the middle pole tab 106.

[0095] In the above structure, the first electrode tab 104 and the middle electrode tab 106 are connected by providing the first connecting portion 503, thereby shortening the electron transmission path between the first electrode tab 104 and the current collecting plate 501, improving the flow capacity of each part of the electrode assembly 10, and thus improving the operating stability of the cylindrical battery cell 7.

[0096] like Figure 10As shown, in some embodiments of the present application, the first connecting portion 503 is bent and extended along the pole piece core 101 toward the center hole 103. In the above structure, the length of the first connecting portion 503 is extended, the connection strength between the first pole tab 104 and the middle pole tab 106 is enhanced, the contact area between the middle pole tab 106 and the current collecting plate 501 is increased, and its current flow capacity and connection strength are improved.

[0097] In some embodiments of the present application, the first connection portion 503 is formed by welding the middle tab 106 and the first tab 104 . For example, the middle tab 106 and the first tab 104 can be connected by laser welding.

[0098] In the above structure, the first connecting portion 503 is formed by melting the materials of the middle tab 106 and the first tab 104 by high temperature heating and cooling, which is easy to manufacture and does not require additional welding materials, thereby improving manufacturing efficiency and reducing production costs.

[0099] In some embodiments of the present application, there are multiple first connection parts 503, which are spaced apart along the circumference of the pole piece core 101. For example, there are four first connection parts 503, and the four welded parts are spaced apart at 90° along the end surface of the saw blade core.

[0100] In the above structure, by increasing the number of first connecting parts 503, the flow path between the middle electrode tab 106 and the first electrode tab 104 is increased, the connection stability between the electrode tab 102 and the current collecting plate is improved, and the consistency of the flow capacity of each part of the electrode assembly 10 is improved.

[0101] like Figure 11 as well as Figure 12 As shown, in some embodiments of the present application, the electrode assembly 10 includes a second connecting portion 504, which is connected between the first electrode tab 104 and the middle electrode tab 106, and the second connecting portion 504 is arranged along the circumference of the central hole 103 and arranged along an annular path.

[0102] In the above structure, by setting the second connecting portion 504, a flow path is formed between the interconnected pole tabs 102, so that the pole tabs 102 of different layers can form a current output flow channel through the connection point, thereby improving the consistency of the flow capacity of each part of the electrode assembly 10.

[0103] In some embodiments of the present application, there are multiple second connection portions 504, which are spaced apart along the radial direction of the pole piece core 101. Optionally, the distance D between two adjacent second connection portions 504 is: 5 mm ≤ D ≤ 15 mm.

[0104] In the above structure, by increasing the number of second connecting parts 504, the contact area between the second connecting parts 504 and the current collecting plate and the pole ear 102 is increased, the connection points are increased, the connection stability between the pole ear 102 and the current collecting plate is improved, and the consistency of the flow capacity of various parts of the electrode assembly 10 is improved.

[0105] In some embodiments of the present application, the second connecting portion 504 includes a first welding ring 505. The first welding ring 505 is connected between the first electrode tab 104 and the middle electrode tab 106. The first welding ring 505 includes a plurality of first welding blocks 507 spaced apart along an annular path. The first welding blocks 507 are formed by welding the first electrode tab 104 and the middle electrode tab 106. In the above structure, the provision of the first welding ring 505 electrically connects the outer first electrode tab 104 and the middle electrode tab 106, shortening the electron transmission path between the outer ring electrode tab and the current collecting disk 501, thereby improving the consistency of the current flow capacity of each part of the electrode assembly 10.

[0106] In some optional embodiments, the electrode assembly 10 further includes a second welding ring 506, which is connected between the middle electrode tab 106 and the second electrode tab 105. The second welding ring 506 includes a plurality of second welding blocks 508 spaced apart along an annular path, and the second welding blocks 508 are formed by welding the second electrode tab 105 and the middle electrode tab 106. In the above structure, the first welding ring 505 is provided to electrically connect the outer first electrode tab 104 with the middle electrode tab 106, and the second welding ring 506 is provided to connect the middle electrode tab 106 with the second electrode tab 105. This increases the current path between electrode assemblies of different electrode layers, shortens the electron transmission path between the outer and inner electrode tabs and the current collecting disk 501, and improves the consistency of the current capacity of each part of the electrode assembly 10.

[0107] In some optional embodiments, the electrode assembly 10 further includes a third welding ring 510, which is connected between the current collecting disk 501 and the second electrode tab 105. The third welding ring 510 includes a plurality of third welding blocks 509 spaced apart along an annular path. The third welding blocks 509 are formed by welding the second electrode tab 105 and the current collecting disk 501. In the above structure, the third welding ring 510 directly electrically connects the inner second electrode tab 105 to the current collecting disk 501, shortening the electron transmission path between the inner ring electrode tab and the current collecting disk 501, thereby improving the consistency of the current flow capacity throughout the electrode assembly 10.

[0108] In some embodiments of the present application, the cylindrical battery cell 7 further includes an insulating member disposed between the electrode core 101 and the outer casing 40 and wrapping the electrode core 101. The second connecting portion 504 is spaced apart from the insulating member. This structure improves the insulation performance between the electrode assembly 10 and the outer casing 40. The spaced apart arrangement of the second connecting portion 504 and the insulating member reduces damage to the insulating member during the manufacturing process, thereby improving the insulation effect.

[0109] An embodiment of the present application provides a battery 2 comprising the aforementioned cylindrical battery cell 7. An embodiment of the present application also provides an electrical device comprising the aforementioned battery 2, which is configured to provide electrical energy. Within the cylindrical battery cell 7, a housing 40 is provided to provide a stable and enclosed interior space for the electrode assembly 10, effectively isolating impurities, moisture, and the like from the external environment, thereby improving the operational stability of the cylindrical battery cell 7. The pole piece winding method employed to form the pole piece core 101 reduces the space occupied by the electrode pieces, improves the space utilization within the housing 40, and enhances the energy density of the cylindrical battery cell 7. Multiple radially stacked tabs 102 are provided on the pole piece core 101, enhancing the current transmission capability of the pole piece core 101. The multiple layers of tabs 102 disperse current and reduce resistance, enabling rapid response during charge and discharge of the battery 2, reducing energy loss and improving overall efficiency. In particular, by electrically connecting the outer first tab 104 to the middle tab 106, the electron transmission path between the outer tabs and the current collecting plate 501 is shortened. This not only reduces the loss during power transmission, but also reduces the risk of lithium deposition near the outer tab due to excessive current density, thereby improving the operational stability of the battery 2.

[0110] 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 make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions 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. A cylindrical battery cell, characterized in that: include: shell; an electrode assembly disposed in the housing, the electrode assembly comprising a pole piece core and a pole lug, the pole piece core having a central hole extending therethrough in an axial direction, the pole lug being connected to an end of the pole piece core along the axial direction, the plurality of pole lugs being stacked radially along the pole piece core, the plurality of pole lugs comprising a first pole lug away from the central hole, a second pole lug close to the central hole, and a middle pole lug disposed between the first pole lug and the second pole lug, the first pole lug being electrically connected to the middle pole lug; A current collecting assembly is electrically connected to the housing. The current collecting assembly is electrically connected to at least the middle tab to electrically connect the electrode assembly and the housing.

2. The cylindrical battery cell according to claim 1, characterized in that: The second electrode tab is electrically connected to the middle electrode tab.

3. The cylindrical battery cell according to claim 1, characterized in that: The plurality of pole tabs are bent toward the center hole and are stacked on the end surface of the pole piece core along the axial direction of the pole piece core.

4. The cylindrical battery cell according to any one of claims 1 to 3, characterized in that: Along the direction from the central hole of the pole piece core toward the edge of the pole piece core, the extension lengths of the plurality of pole tabs along the axial direction of the pole piece core increase sequentially.

5. The cylindrical battery cell according to claim 4, characterized in that: The current collecting assembly comprises: A current collecting plate, connected to the tab by welding; The current collecting connection portion has one end connected to the peripheral side of the current collecting disc and the other end connected to the housing to electrically connect the current collecting disc and the housing.

6. The cylindrical battery cell according to claim 5, characterized in that: The diameter of the current collecting disk is smaller than the diameter of the pole piece winding core, and the edge of the current collecting disk is spaced apart from at least a portion of the first pole tab.

7. The cylindrical battery cell according to claim 5, characterized in that: The electrode assembly includes a first connecting portion, which is connected between the first electrode tab and the middle electrode tab. The first connecting portion extends along the edge of the electrode core toward the center hole and connects the first electrode tab to the middle electrode tab.

8. The cylindrical battery cell according to claim 7, characterized in that: The first connecting portion bends and extends along the pole piece core toward the central hole.

9. The cylindrical battery cell according to claim 7, characterized in that: The first connecting portion is formed by welding the middle tab and the first tab.

10. The cylindrical battery cell according to claim 7, characterized in that: There are multiple first connection parts, and the multiple first connection parts are arranged at intervals along the circumference of the pole piece core.

11. The cylindrical battery cell according to any one of claims 5 to 10, characterized in that: The electrode assembly includes a second connecting portion connected to the first electrode tab and the middle electrode tab. The second connecting portion is disposed along the circumference of the central hole and arranged along an annular path.

12. The cylindrical battery cell according to claim 11, characterized in that: There are multiple second connection parts, and the multiple second connection parts are arranged at intervals along the radial direction of the pole piece core.

13. The cylindrical battery cell according to claim 11, characterized in that: The second connecting portion includes: a first welding ring, the first welding ring is connected between the first electrode tab and the middle electrode tab, the first welding ring includes a plurality of first welding blocks spaced apart along an annular path, and the first welding blocks are formed by welding the first electrode tab and the middle electrode tab.

14. The cylindrical battery cell according to claim 11, characterized in that: The cylindrical battery cell further includes an insulating member, which is disposed between the pole piece core and the housing and wraps the pole piece core, and the second connecting portion is spaced apart from the insulating member.

15. A battery device, characterized in that: The invention comprises a cylindrical battery cell according to any one of claims 1 to 14.

16. An electrical device, characterized in that: The electric device comprises the battery device according to claim 15, and the battery device is used to provide electric energy.

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