Cylindrical battery monomer, battery and power utilization device

Abstract

The utility model provides a cylindrical battery monomer, a battery and a power utilization device, and belongs to the technical field of batteries. The cylindrical battery cell comprises: an electrode assembly which is of a winding structure and comprises a first tab; an accommodating space for accommodating the electrode assembly is defined in the shell; the current collecting component comprises a first connecting part and a second connecting part which are connected, the second connecting part is connected to the outer edge of the first connecting part and protrudes in the direction away from the electrode assembly, the first connecting part is electrically connected with the first tab, and the second connecting part is directly connected with the shell; the first connecting part is provided with at least one first notch which is recessed from the outer edge to the center, and the first notch is used for communicating spaces on the two sides of the first connecting part in the thickness direction. According to the invention, the first gap is formed in the current collecting component, so that the exhaust efficiency of the cylindrical battery monomer can be improved.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0003] During the battery's charge and discharge cycles, the electrode assembly releases a significant amount of gas over a period of time. Failure to quickly expel the gas from the battery cells can lead to combustion, explosion, and other issues. Therefore, improving the exhaust efficiency of battery cells has become a pressing issue. Utility Model Content

[0004] The present application aims to solve at least one of the technical problems existing in the background art. To this end, one object of the present application is to provide a cylindrical battery cell, a battery, and an electrical device to improve the exhaust efficiency of the cylindrical battery cell.

[0005] An embodiment of the first aspect of the present application provides a cylindrical battery cell, comprising: an electrode assembly, which is a wound structure, the electrode assembly including a first tab; a shell, which internally defines a storage space for accommodating the electrode assembly; and a current collecting member, comprising a first connecting portion and a second connecting portion connected to each other, the second connecting portion being connected to the outer edge of the first connecting portion and protruding in a direction away from the electrode assembly, the first connecting portion being electrically connected to the first tab, and the second connecting portion being directly connected to the shell, the first connecting portion having at least one first notch recessed from its outer edge toward the center, the first notch being used to connect the spaces on both sides of the first connecting portion along its thickness direction.

[0006] In the technical solution of the embodiment of the present application, the first notch of the first connecting part is located on the outside of the first connecting part close to the shell, and the first notch connects the space on both sides of the first connecting part along its thickness direction, so that the first notch can connect the space between the electrode assembly and the side wall of the shell. In this way, the gas generated outside the electrode assembly can be discharged directly through the first notch, reducing the exhaust distance of the gas generated outside the electrode assembly and improving the exhaust efficiency; and the second connecting part is connected to the outer edge of the first connecting part and protrudes in the direction away from the electrode assembly, so that the weld mark between the current collecting component and the shell can be staggered with the first notch, thereby improving the reliability of the current collecting component in terms of flow and exhaust.

[0007] In some embodiments, the cylindrical battery cell further includes an end cap located on a side of the current collecting member away from the electrode assembly and connected to the housing to seal the opening of the accommodating space; the end cap is provided with a pressure relief component spaced apart from the first connecting portion and configured to break open when the internal pressure of the cylindrical battery cell reaches a preset threshold. The spacing between the end cap and the first connecting portion allows the two to form a space of a certain height, providing a sufficient exhaust channel for discharged gases, further improving the exhaust efficiency of the cylindrical battery cell, and reducing the risk of the current collecting member contacting the pressure relief component when deformed, thereby improving the reliability of the pressure relief component.

[0008] In some embodiments, there are multiple second connecting portions, which are spaced apart along the periphery of the first connecting portion, with second gaps formed between adjacent second connecting portions. The second gaps can provide the second connecting portions with a certain degree of deformation, allowing the second connecting portions to fit tightly against the inner wall of the housing, thereby enhancing the reliability of the connection between the second connecting portions and the housing.

[0009] In some embodiments, the first notch and the second notch are interconnected. The second notch exposes the inner wall of the housing. The first notch and the second notch are connected, so that the first notch can be directly connected to the inner wall of the housing, thereby forming a larger space between the first notch and the inner wall of the housing, which can provide a larger exhaust channel for gas discharge and further improve the exhaust efficiency of the cylindrical battery cell.

[0010] In some embodiments, the number of the first notches and the second notches is equal, and the first notches are arranged in a one-to-one correspondence with the second notches. This improves the fit between the second connecting portion and the inner wall of the housing while also making the exhaust passage formed at the first notches larger, thereby improving the stability of the cylindrical battery cell and thereby improving the overall performance of the cylindrical battery cell.

[0011] In some embodiments, the housing includes a sidewall, and on a projection plane perpendicular to the winding axis of the electrode assembly, the orthographic projection of the gap between the electrode assembly and the inner wall surface of the sidewall at least partially overlaps with the orthographic projection of the first notch. In other words, the gap between the electrode assembly and the inner wall surface of the housing sidewall is directly opposite the first notch, allowing gas generated outside the electrode assembly to be discharged directly through the first notch, further reducing the exhaust distance of gas generated outside the electrode assembly and further improving exhaust efficiency.

[0012] In some embodiments, the electrode assembly further comprises a main body, the first tab being located at an end of the main body along the winding axis of the electrode assembly, and the maximum diameter of the first connecting portion being less than or equal to the inner diameter of the housing and greater than the diameter of the main body. In this manner, while the second connecting portion, located outside the first connecting portion, can be located within the housing and directly connected to the inner surface of the housing sidewall, the orthographic projection of the main body on the first connecting portion is located within the first connecting portion, thereby enabling the first notch of the first connecting portion to be aligned with the gap between the main body and the inner surface of the housing sidewall, allowing gas generated outside the electrode assembly to be discharged directly through the first notch.

[0013] In some embodiments, the first connecting portion further includes a through hole that is disposed opposite and connected to the center hole of the electrode assembly. Thus, gas discharged from the electrode assembly to the center hole can be discharged through the through hole, reducing airflow accumulation in the center hole and improving exhaust efficiency.

[0014] In some embodiments, the first connecting portion further comprises a plurality of hollow grooves spaced apart circumferentially around the through-hole, with each of the plurality of hollow grooves extending away from the through-hole. The hollow grooves can also form exhaust channels for gas within the cylindrical battery cell. Furthermore, the hollow grooves can reduce the structural strength of the current collecting member, allowing the current collecting member to rupture when excessive pressure is generated by a large amount of gas within the electrode assembly, thereby increasing the exhaust channel and further improving the exhaust efficiency of the cylindrical battery cell.

[0015] In some embodiments, at least one of the plurality of hollow grooves is connected to the through-hole. This allows, on the one hand, gas exhausted through the through-hole to be directed to the hollow groove for discharge, providing guidance for the gas inside the cylindrical battery cell and reducing the accumulation of airflow at the center hole. On the other hand, the hollow groove extends away from the through-hole and is connected to the through-hole, making it easier for the first connection portion to rupture when the pressure inside the cylindrical battery cell is excessive, thereby providing a certain degree of pressure relief, reducing the risk of explosion of the cylindrical battery cell, and improving the safety of the cylindrical battery cell.

[0016] In some embodiments, the plurality of hollow grooves include at least one first hollow groove and at least one second hollow groove. The first hollow groove communicates with the through-hole, and the second hollow groove is spaced apart from the through-hole. The first hollow grooves and the second hollow grooves are alternately spaced along the circumference of the first connecting portion. This balances the exhaust channel area and structural strength of the current collecting member, thereby ensuring the stability of the cylindrical battery cells to a certain extent.

[0017] In some embodiments, the hollow grooves and the first notches are alternately spaced along the circumference of the first connecting portion. This maintains a certain distance between the hollow grooves and the first notches, ensuring that the first connecting portion has a certain strength. Under normal pressure conditions within the cylindrical battery cell, the current collecting member can form a stable electrical connection with the electrode assembly and the housing.

[0018] In some embodiments, the first connecting portion further includes at least one positioning hole extending through the first connecting portion along its thickness and spaced apart from the through-hole. The positioning hole facilitates quick positioning of the current collecting member, the electrode assembly, and the housing during installation of the current collecting member within the housing, thereby improving the production efficiency of cylindrical battery cells and increasing production capacity.

[0019] In some embodiments, the housing includes a sidewall, the inner surface of which is parallel to the winding axis of the electrode assembly, and the second connecting portion is welded to the inner surface of the sidewall. This improves the connection strength between the second connecting portion and the sidewall and creates a sufficient exhaust space on the side of the first connecting portion adjacent to the second connecting portion, further improving the exhaust efficiency of the cylindrical battery cell.

[0020] In some embodiments, the cylindrical battery cell further includes an electrode terminal insulated from the housing; wherein the electrode assembly includes a second tab having a different polarity than the first tab, the second tab being electrically connected to the electrode terminal. The tabs having different polarities can effectively maintain a stable circuit state between the positive and negative electrodes of the cylindrical battery cell, enabling the cylindrical battery cell to operate normally.

[0021] An embodiment of the second aspect of the present application provides a battery, which includes the cylindrical battery cell in the above embodiment.

[0022] An embodiment of the third aspect of the present application provides an electrical device, which includes the battery in the above embodiment.

[0023] 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

[0024] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0025] Figure 1 A schematic structural diagram of a vehicle according to some embodiments of the present application;

[0026] Figure 2 Schematic diagram of the exploded structure of batteries according to some embodiments of the present application;

[0027] Figure 3 A schematic diagram of the three-dimensional structure of a cylindrical battery cell according to some embodiments of the present application;

[0028] Figure 4 This is a schematic top view of a cylindrical battery cell according to some embodiments of the present application;

[0029] Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure in the AA direction;

[0030] Figure 6 for Figure 5 A schematic diagram of the enlarged structure in the middle dotted box;

[0031] Figure 7 This is a schematic diagram of the exploded structure of a cylindrical battery cell according to some embodiments of the present application;

[0032] Figure 8 Schematic diagram of the top view of the current collecting component in some embodiments of the present application;

[0033] Figure 9 This is a schematic side structural diagram of a current collecting component in some embodiments of the present application;

[0034] Figure 10 Schematic diagrams of the three-dimensional structure of current collecting components of other embodiments of the present application;

[0035] Figure 11 Schematic diagrams of top views of current collecting components according to other embodiments of the present application;

[0036] Figure 12 Schematic side views of the current collecting components of other embodiments of the present application;

[0037] Figure 13 Schematic diagram of the exploded structure of cylindrical battery cells according to other embodiments of the present application.

[0038] Description of reference numerals:

[0039] Vehicles 1000;

[0040] A first hollow groove 2341 and a second hollow groove 2342;

[0041] Battery 100;

[0042] Controller 200, main body 211, tabs 212, first tab 212a, second tab 212b, center hole 213, electrode terminal 214, current collecting plate 215, first connecting portion 231, first notch 231a, second connecting portion 232, second notch 232a, through hole 233, hollow groove 234, positioning hole 235, aluminum nail 261, plastic nail 262;

[0043] Motor 300;

[0044] Box body 10, first part 11, second part 12;

[0045] Cylindrical battery cell 20, electrode assembly 21, housing 22, current collecting member 23, pressure relief component 24, end cap 25, cover plate 26;

[0046] First angle R1, second angle R2. DETAILED DESCRIPTION

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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).

[0053] 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.

[0054] 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.

[0055] Under extreme conditions, cylindrical battery cells may experience thermal runaway, which can lead to rapid decomposition of the electrolyte and other battery materials, generating a large amount of gas inside the shell. If the gas cannot be discharged in time, it will cause excessive pressure inside the cylindrical battery cell and become dangerous.

[0056] Gas may be generated in various locations within the electrode assembly. To effectively discharge gas generated within the electrode assembly, the electrode assembly has a central hole. Gas generated throughout the entire electrode assembly converges into the central hole and is discharged through the central hole. However, for gas generated outside the electrode assembly, the distance from the central hole creates a longer path for gas flow, preventing timely discharge of the gas generated outside the electrode assembly.

[0057] Furthermore, the compact internal structure of cylindrical battery cell housings can easily obstruct gas flow. For example, the current collecting member within the housing, along with the weld marks formed by the current collecting member, the tabs, and the electrode terminals, can block the flow of gas, trapping most of the gas in the gap between the housing and the electrode assembly, making it difficult to escape.

[0058] Based on the above considerations, a cylindrical single-cell monomer is designed, comprising a shell, an electrode assembly located within the shell, and a current collecting component. The current collecting component comprises a first connecting portion electrically connected to the first tab of the electrode assembly and a second connecting portion electrically connected to the shell, the first connecting portion having at least one first notch recessed from its outer edge toward the center. That is, the first notch is located on the outside of the first connecting portion close to the shell, and the first notch connects the spaces on both sides of the first connecting portion along the thickness direction, so that the first notch can connect the space between the electrode assembly and the side wall of the shell. In this way, the gas generated outside the electrode assembly can be discharged directly through the first notch, reducing the exhaust distance of the gas generated outside the electrode assembly and improving the exhaust efficiency. In addition, the second connecting portion is connected to the outer edge of the first connecting portion and protrudes in the direction away from the electrode assembly, so that the weld mark between the current collecting component and the shell can be staggered with the first notch, thereby improving the reliability of the flow and exhaust of the current collecting component.

[0059] The cylindrical battery cells disclosed in the embodiments of this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the cylindrical battery cells and batteries disclosed in this application can be used to improve the exhaust efficiency of the cylindrical battery cells and enhance battery reliability.

[0060] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0061] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0062] Please refer to Figure 1 , Figure 1A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can 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 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. 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.

[0063] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000 , but also 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 .

[0064] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the exploded structure of a battery provided in some embodiments of the present application. The battery 100 includes a housing 10 and cylindrical battery cells 20, which are housed within the housing 10. The housing 10 is used to provide a storage space for the cylindrical battery cells 20, and the housing 10 can have a variety of structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the cylindrical battery cells 20. The second portion 12 can be a hollow structure with one end open, and the first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. The first portion 11 and the second portion 12 can also be hollow structures with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have a variety of shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0065] In the battery 100, there may be multiple cylindrical battery cells 20, and the multiple cylindrical battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple cylindrical battery cells 20. The multiple cylindrical battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entirety of the multiple cylindrical battery cells 20 may be housed within the housing 10. Of course, the battery 100 may also be a battery module formed by first connecting multiple cylindrical battery cells 20 in series, in parallel, or in a hybrid connection, and then the multiple battery modules may be connected in series, in parallel, or in a hybrid connection to form an entirety, and then housed within the housing 10. The battery 100 may also include other structures. For example, the battery 100 may also include a busbar component for electrically connecting the multiple cylindrical battery cells 20.

[0066] A cylindrical battery cell 20 is the smallest unit that makes up a battery. Each cylindrical battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. Cylindrical battery cells 20 can be cylindrical, flat, rectangular, or in other shapes. Unless otherwise specified, the embodiments of this application use cylindrical battery cells as an example.

[0067] refer to Figures 3 to 9 , Figure 3 A schematic diagram of the three-dimensional structure of a cylindrical battery cell according to some embodiments of the present application; Figure 4 This is a schematic top view of a cylindrical battery cell according to some embodiments of the present application; Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure in the AA direction; Figure 6 for Figure 5 A schematic diagram of the enlarged structure in the middle dotted box; Figure 7 This is a schematic diagram of the exploded structure of a cylindrical battery cell according to some embodiments of the present application; Figure 8 Schematic diagram of the top view of the current collecting component in some embodiments of the present application; Figure 9 This is a schematic side structural diagram of a current collecting component in some embodiments of the present application.

[0068] An embodiment of the present application provides a cylindrical battery cell, including: an electrode assembly 21, which is a wound structure, and the electrode assembly 21 includes a first electrode tab 212a; a shell 22, which defines an accommodating space for accommodating the electrode assembly 21; and a current collecting member 23, including a first connecting portion 231 and a second connecting portion 232 connected to each other, the second connecting portion 232 being connected to the outer edge of the first connecting portion 231 and protruding in a direction away from the electrode assembly 21, the first connecting portion 231 being electrically connected to the first electrode tab 212a, and the second connecting portion 232 being directly connected to the shell 22, and the first connecting portion 231 having at least one first notch 231a recessed from its outer edge toward the center, and the first notch 231a being used to connect the space on both sides of the first connecting portion 231 along its thickness direction.

[0069] The housing 22 is a component used to form the internal environment of the cylindrical battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 21, electrolyte, and other components. The housing 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylinder, a hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the electrode assembly 21. The housing 22 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0070] The electrode assembly 21 is the component where the electrochemical reaction occurs in the cylindrical battery cell 20. One or more electrode assemblies 21 may be contained in the housing 22. The electrode assembly 21 is mainly formed by winding and placing a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the main body 211 of the electrode assembly 21, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute a tab 212. The tab 212 may include a first tab 212a and a second tab 212b of different polarities, wherein the first tab 212a and the second tab 212b may be located together in a section of the main body 211 or respectively at both ends of the main body 211. The first tab 212a may be located on one of the positive electrode sheet or the negative electrode sheet, and the second tab 212b may be located on the other of the positive electrode sheet or the negative electrode sheet. During the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 22 a connects the electrode terminal to form a current loop.

[0071] The current collecting member 23 is electrically connected to the first electrode tab 212a for outputting or inputting electric energy of the cylindrical battery cell 20. The current collecting member 23 may be made of a conductive material, such as copper or a copper alloy.

[0072] The first connection portion 231 of the current collecting member 23 may be electrically connected to the first electrode tab 212 a by welding, such as laser welding, ultrasonic welding, or friction welding.

[0073] There is a gap between the electrode assembly 21 and the inner wall of the shell 22 , and the first notch 231 a can connect the space between the electrode assembly 21 and the inner wall of the shell 22 and the space on the side of the first connecting portion 231 away from the electrode assembly 21 .

[0074] In some embodiments, the orthographic projection of the gap between the electrode assembly 21 and the side wall of the housing 22 on the current collecting member 23 overlaps with at least a portion of the first notch 231a. In other words, the entire first notch 231a is connected to the gap between the electrode assembly 21 and the inner wall of the housing 22, or a portion of the first notch 231a is connected to the gap between the electrode assembly 21 and the inner wall of the housing 22, and the remaining portion is covered by the electrode assembly 21.

[0075] In some embodiments, the number of the first notch 231a may be only one. In other embodiments, the number of the first notch 231a may be multiple, for example, 2, 3, 4 or more.

[0076] In some embodiments, when there are multiple first notches 231 a , the multiple first notches 231 a may be evenly spaced apart along the circumference of the first connecting portion 231 .

[0077] refer to Figure 8 The angle between the lines from both sides of the first notch 231 a to the center of the first connection portion 231 is the first angle R1 , and the first angles R1 corresponding to the plurality of first notches 231 a are all equal.

[0078] In other embodiments, when there are multiple first notches 231a, the multiple first notches 231a may be unevenly spaced along the circumference of the first connecting portion 231. For example, the first angles R1 corresponding to the multiple first notches 231a may not be equal, or only the first angles R1 corresponding to some of the first notches 231a may be equal.

[0079] In some embodiments, the first angle R1 may be 10° to 60°.

[0080] In some embodiments, the shape of the first notch 231 a may include, but is not limited to, regular or irregular shapes such as a triangle, a U-shape, a rectangle, a semicircle, or a polygon.

[0081] In some embodiments, the second connection portion 232 may be perpendicular to the first connection portion 231 , so that the second connection portion 232 fits more closely against the inner wall of the housing 22 .

[0082] In some embodiments, the height of the second connection portion 232 can be 1 mm to 3 mm, and can be 1 mm, 2 mm, 2.5 mm, or 3 mm, for example. Within the above range, on the one hand, the second connection portion 232 can enclose a larger space with the first connection portion 231, providing a larger exhaust channel for the gas generated inside the cylindrical battery cell, and the area of ​​the second connection portion 232 itself is large enough to form a large area of ​​contact with the shell 22, thereby forming a more stable electrical connection with the shell 22. On the other hand, the size of the second connection portion 232 itself is not too large, and it does not occupy too much space in the shell 22, keeping the structure of the cylindrical battery cell compact.

[0083] In the above technical solution, the first notch 231a of the first connecting portion 231 is located on the outside of the first connecting portion 231 near the shell 22, and the first notch 231a connects the space on both sides of the first connecting portion 231 along its thickness direction, so that the first notch 231a can connect the space between the electrode assembly 21 and the shell 22. In this way, the gas generated outside the electrode assembly 21 can be discharged directly through the first notch 231a, reducing the exhaust distance of the gas generated outside the electrode assembly 21 and improving the exhaust efficiency. In addition, the second connecting portion 232 extends along the outer edge of the first connecting portion 231 and protrudes in the direction away from the electrode assembly 21, which can stagger the weld mark between the current collecting component and the shell 22 with the first notch 231a, thereby improving the reliability of the current collecting component's flow and exhaust.

[0084] refer to Figures 5 to 7 In some embodiments, the cylindrical battery cell further includes an end cover, which is located on a side of the current collecting member away from the electrode assembly and is connected to the shell to close the opening of the accommodating space; a pressure relief component is provided on the end cover, the pressure relief component is spaced apart from the first connecting portion, and the pressure relief component is constructed to break when the internal pressure of the cylindrical battery cell reaches a preset threshold.

[0085] The end cap 25 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the cylindrical battery cell 20 from the external environment. The end cap can be located on the side of the current collecting member 23 away from the electrode assembly 21. Without limitation, the shape of the end cap 25 can be adapted to the shape of the shell 22 to match the shell 22. The shell 22 and the end cap 25 can be independent components, and an opening can be provided on the shell 22. The internal environment of the cylindrical battery cell 20 is formed by covering the opening with the end cap 25. Without limitation, the end cap 25 and the shell 22 can also be integrated. Specifically, the end cap 25 and the shell 22 can form a common connection surface before other components are put into the shell. When the interior of the shell 22 needs to be encapsulated, the end cap 25 is covered with the shell 22.

[0086] The end cap 25 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0087] refer to Figure 7 The pressure relief component 24 is located on a side of the current collecting member 23 away from the electrode assembly 21. The pressure relief component 24 is configured to break open when the internal pressure of the cylindrical battery cell reaches a certain threshold, allowing the gas inside the cylindrical battery cell to be discharged, thereby reducing the internal pressure.

[0088] The pressure relief member 24 can be a weak structure located on the end cap 25. When the internal pressure of the cylindrical battery cell 20 increases to a certain level, the weak structure will be destroyed first, allowing gas to escape and relieve pressure. In some embodiments, the pressure relief member 24 can be a structural weak point formed by one or more notched grooves provided at designated locations on the housing 22.

[0089] The end cap 25 and the first connecting portion 231 are spaced apart so that the two form a space of a certain height, providing a sufficient exhaust channel for the exhausted gas, further improving the exhaust efficiency of the cylindrical battery cell, and at the same time reducing the risk of the current collecting component 23 touching the pressure relief component 24 when deformed, thereby improving the reliability of the pressure relief component 24.

[0090] refer to Figures 10 to 13 , Figure 10 Schematic diagrams of the three-dimensional structure of current collecting components of other embodiments of the present application; Figure 11 Schematic diagrams of top views of current collecting components according to other embodiments of the present application; Figure 12 Schematic side views of the current collecting components of other embodiments of the present application; Figure 13 Schematic diagram of the exploded structure of cylindrical battery cells according to other embodiments of the present application.

[0091] According to some embodiments of the present application, there are multiple second connection parts 232 , and the multiple second connection parts 232 are arranged at intervals along the outer periphery of the first connection part 231 , and second gaps 232 a are formed between adjacent second connection parts 232 .

[0092] The second notch 232a can provide a certain degree of deformation capability for the second connecting portion 232. When the second connecting portion 232 extends into the inner wall of the housing 22, the second connecting portion 232 can deform to adapt to the size of the housing 22, allowing the second connecting portion 232 to fit tightly against the inner wall of the housing 22, thereby improving the electrical connection performance between the second connecting portion 232 and the inner wall of the housing 22.

[0093] In some embodiments, the number of the second notch 232a may be only one. In other embodiments, the number of the second notch 232a may be multiple, for example, 2, 3, 4 or more.

[0094] In some embodiments, when there are multiple second notches 232a, the multiple second notches 232a can be evenly spaced around the outer edge of the first connecting portion 231. The angle between the lines connecting the two sides of the second notch 232a and the center of the first connecting portion 231 is the second angle R2, and the second angles R2 corresponding to the multiple second notches 232a are all equal.

[0095] In other embodiments, when there are multiple second notches 232a, the plurality of second notches 232a may be unevenly spaced around the outer edge of the first connecting portion 231. For example, the second angles R2 corresponding to the plurality of second notches 232a may not be equal, or only some of the second notches 232a may have the same second angles R2.

[0096] In some embodiments, the shape of the second notch 232a may include, but is not limited to, regular or irregular shapes such as a triangle, a U-shape, a rectangle, a semicircle, or a polygon.

[0097] It is understandable that, in other embodiments, the second connection portion 232 may also extend along the outer edge of the first connection portion 231 to form a ring shape.

[0098] In the above technical solution, the second notch 232a can provide a certain deformation ability for the second connecting portion 232, so that the second connecting portion 232 can fit tightly with the inner wall of the shell 22, thereby enhancing the reliability of the connection between the second connecting portion 232 and the shell 22.

[0099] According to some embodiments of the present application, the first notch 231 a and the second notch 232 a are communicated with each other.

[0100] The second connection portion 232 is electrically connected to the inner wall of the housing 22. A second notch 232a is formed in the second connection portion 232, allowing the second notch 232a to expose the inner wall of the housing 22. The first notch 231a is connected to the second notch 232a, allowing the first notch 231a to directly communicate with the inner wall of the housing 22. In other words, the absence of the second connection portion 232 between the first notch 231a and the housing 22 increases the gap between the first notch 231a and the housing 22.

[0101] The first notch 231a and the second notch 232a may be connected to each other in such a way that the orthographic projection of the second notch 232a on the first connecting portion 231 is located in the plane where the first notch 231a is located; or the orthographic projection of the second notch 232a on the first connecting portion 231 partially coincides with the plane where the first notch 231a is located.

[0102] In the above technical solution, a larger space is formed between the first notch 231a and the inner wall of the shell 22, which can provide a larger exhaust channel for the discharge of gas, further improving the exhaust efficiency of the cylindrical battery cell.

[0103] It is understandable that, in other embodiments, the first notch 231a and the second notch 232a may not be connected to each other.

[0104] According to some embodiments of the present application, the number of the first notches 231 a and the number of the second notches 232 a are multiple and equal, and the multiple first notches 231 a and the multiple second notches 232 a are arranged in a one-to-one correspondence.

[0105] The one-to-one correspondence arrangement means that the first notch 231a is connected to the corresponding second notch 232a. The definition of the connection between the first notch 231a and the second notch 232a can refer to the above description. For example, the number of the first notch 231a and the second notch 232a can be four.

[0106] It is understandable that, in other embodiments, the number of the first notches 231a may be greater than the number of the second notches 232a, and each second notch 232a corresponds to a different first notch 231a and is connected to the corresponding first notch 231a.

[0107] In some other embodiments, the number of the first notches 231 a may be smaller than the number of the second notches 232 a , and each first notch 231 a corresponds to a different second notch 232 a and is connected to the corresponding second notch 232 a .

[0108] In the above technical solution, multiple first notches 231a and multiple second notches 232a are arranged in a one-to-one correspondence. On the one hand, each first notch 231a can form a larger exhaust channel. On the other hand, the number of second notches 232a is not too large compared to the number of first notches 231a, so that the second connecting portion 232 has a sufficient size to form an electrical connection with the shell 22, which is beneficial to improving the stability of the cylindrical battery cell and thus improving the overall performance of the cylindrical battery cell.

[0109] According to some embodiments of the present application, the shell 22 includes a side wall, and on a projection plane perpendicular to the winding axis of the electrode assembly 21, the orthographic projection of the gap between the electrode assembly 21 and the inner wall surface of the side wall at least partially overlaps with the orthographic projection of the first notch 231a.

[0110] The sidewalls of the housing are used to enclose a space for accommodating the electrode assembly. A gap is defined between the electrode assembly 21 and the inner surface of the sidewall, through which gas generated outside the electrode assembly 21 is discharged. The orthographic projection of the gap between the electrode assembly 21 and the inner surface of the sidewall at least partially overlaps with the orthographic projection of the first notch 231a. That is, along the winding axis of the electrode assembly 21, the gap between the electrode assembly 21 and the inner surface of the sidewall at least partially faces the first notch 231a.

[0111] In the above technical solution, the gap between the electrode assembly 21 and the inner wall surface of the side wall of the shell 22 is at least partially opposite to the first notch 231a, and the gas generated outside the electrode assembly 21 can be directly discharged through the first notch 231a, further reducing the exhaust distance of the gas generated outside the electrode assembly 21 and further improving the exhaust efficiency.

[0112] According to some embodiments of the present application, the electrode assembly 21 also includes a main body 211, the first electrode tab 212a is located at the end of the main body 211 along the winding axis direction of the electrode assembly 21, and the maximum diameter of the first connecting portion 231 is less than or equal to the inner diameter of the shell 22, and greater than the diameter of the main body.

[0113] The maximum diameter of the first connection portion 231 referred to herein refers to the diameter of a portion of the first connection portion 231 where the first notch 231 a is not provided.

[0114] The maximum diameter of the first connection part 231 is less than or equal to the inner diameter of the shell 22, that is, the first connection part 231 can be located inside the shell 22, so that the second connection part 232 connected to the edge of the first connection part 231 can also be located inside the shell 22, so that the second connection part 232 can be directly connected to the inner wall surface of the side wall of the shell 22.

[0115] It is understood that if the maximum diameter of the first connecting portion 231 is smaller than the inner diameter of the housing 22, the angle between the first connecting portion 231 and the second connecting portion 232 can be 90° or greater. If the angle between the first connecting portion 231 and the second connecting portion 232 is 90°, the second connecting portion 232 can be entirely attached to the inner surface of the sidewall of the housing. If the angle between the first connecting portion 231 and the second connecting portion 232 is greater than 90°, the end of the second connecting portion 232 away from the first connecting portion 231 is connected to the inner surface of the sidewall of the housing 22.

[0116] The maximum diameter of the first connecting portion 231 is greater than the diameter of the main body, that is, the positive projection of the main body on the first connecting portion 231 is located inside the first connecting portion 231, so that the first notch 231a of the first connecting portion 231 can be opposite to the gap between the main body and the inner wall surface of the side wall of the shell 22.

[0117] In the above technical solution, while the second connection part 232 on the periphery of the first connection part 231 can be located inside the shell 22 and directly connected to the inner wall surface of the side wall of the shell 22, the gas generated outside the electrode assembly 21 can be directly discharged through the first notch 231a.

[0118] refer to Figure 5 as well as Figures 8 to 12 According to some embodiments of the present application, the first connecting portion 231 further includes: a through hole 233 , which is arranged opposite to and connected to the central hole 213 of the electrode assembly 21 .

[0119] The central hole 213 can be formed by winding the electrode sheets of the electrode assembly 21. The central hole 213 extends along the height of the cylindrical battery cell and penetrates the electrode assembly 21. The central hole 213 can be a cylindrical through-hole 233. The central axis of the central hole 213 can be coaxial with the central axis of the housing 22. Gas generated by the electrode assembly 21 can be discharged through the central hole 213.

[0120] The through hole 233 is arranged opposite to the central hole 213 of the electrode assembly 21 , which means that the orthographic projection of the central hole 213 on the first connecting portion 231 at least partially overlaps with the through hole 233 .

[0121] The through hole 233 may be a hole of any shape, for example, a diamond shape or a circle.

[0122] In some embodiments, the number of the through hole 233 may be one. In other embodiments, the number of the through hole 233 may also be multiple, and each of the multiple through holes 233 is connected to the central hole 213 .

[0123] In some embodiments, the through hole 233 may be located in a central area of ​​the first connector, and a center line of the through hole 233 may coincide with a center line of the central hole 213 .

[0124] In the above technical solution, the gas discharged from the electrode assembly 21 to the central hole 213 can be discharged through the through hole 233, thereby reducing the accumulation of the airflow in the central hole 213 and improving the exhaust efficiency.

[0125] refer to Figures 8 to 12 According to some embodiments of the present application, the first connecting portion 231 further includes: a plurality of hollow grooves 234 arranged at intervals along the circumference of the through hole 233 , and any one of the plurality of hollow grooves 234 extends in a direction away from the through hole 233 .

[0126] In some embodiments, multiple hollow grooves 234 can be evenly spaced along the circumference of the through hole 233. In this way, multiple hollow grooves 234 can evenly correspond to various parts of the electrode assembly 21 and provide exhaust channels for the gas generated in various parts of the electrode assembly 21.

[0127] In other embodiments, the plurality of hollow grooves 234 may also be arranged unevenly along the circumference of the through hole 233 .

[0128] The hollow groove 234 extends in a direction away from the through hole 233 to form an elongated strip, so that the hollow groove 234 itself has a larger area, which can increase the amount of gas discharged from the hollow groove 234. In addition, the elongated design can increase the speed at which gas is discharged from the hollow groove 234.

[0129] The number of hollow grooves 234 can be 2, 3, 4, or more. For example, the number of hollow grooves 234 can be 4. Within this range, a larger exhaust channel can be provided for gas. Furthermore, the number of hollow grooves 234 in the first connecting portion 231 is not excessive, and the non-hollowed area of ​​the first connecting portion 231 is not too small, thereby maintaining the strength of the first connecting portion 231 and providing a larger welding space for welding the first connecting portion 231 to the first tab 212a.

[0130] In some embodiments, when there are four hollow grooves 234, the four hollow grooves 234 can form a cross-like shape. That is, the two oppositely disposed hollow grooves 234 extend in opposite directions. This ensures that the strength of the first connecting portion 231 is maintained high and a large welding space is provided for the welding of the first electrode tab 212a. At the same time, the hollow grooves 234 can provide a uniform exhaust channel for the gas generated in various parts of the electrode assembly 21.

[0131] In the above technical solution, the hollow groove 234 can also form an exhaust channel for the gas inside the cylindrical battery cell, and the hollow groove 234 can reduce the structural strength of the current collecting component 23, so that when a large amount of gas is generated inside the electrode assembly 21 and the pressure is too high, the current collecting component 23 can rupture, thereby increasing the exhaust channel.

[0132] According to some embodiments of the present application, at least one of the plurality of hollow grooves 234 is connected to the through hole 233 .

[0133] Among the multiple hollow grooves 234 , only one hollow groove 234 may be connected to one through hole 233 , or more than one hollow grooves 234 may be connected to the through hole 233 .

[0134] The hollow groove 234 and the through hole 233 can be connected so that the hollow groove 234 and the through hole 233 are partially connected. Since the hollow groove 234 and the through hole 233 are connected, a larger exhaust channel can be provided for gas, thereby increasing the amount of gas exhausted. When the pressure inside the cylindrical battery cell reaches a certain threshold, the connected hollow groove 234 and the through hole 233 are more likely to rupture, which helps to accelerate the exhaust of gas inside the cylindrical battery cell.

[0135] In some embodiments, if more than one hollow groove 234 is connected to the through hole 233, at least two of the plurality of hollow grooves 234 connected to the through hole 233 are located on opposite sides of the through hole 233 and extend away from each other. In other words, the two opposing hollow grooves 234 are connected by the through hole 233 and are located on the same straight line. This allows the two opposing hollow grooves 234 to form a longer strip, further increasing the gas discharge velocity at these locations.

[0136] In the above technical solution, at least one of the multiple hollow grooves 234 is connected to the through hole 233. On the one hand, this allows the gas exhausted through the through hole 233 to be directed to the hollow groove 234 for discharge, providing guidance for the gas inside the cylindrical battery cell and reducing the accumulation of airflow at the center hole 213. On the other hand, it makes the first connecting portion 231 more likely to rupture when the pressure inside the cylindrical battery cell is excessive, further reducing the risk of cylindrical battery cell explosion and improving the safety of the cylindrical battery cell.

[0137] According to some embodiments of the present application, the plurality of hollow grooves 234 include at least one first hollow groove 2341 and at least one second hollow groove 2342, the first hollow groove 2341 is connected to the through hole 233, the second hollow groove 2342 is spaced apart from the through hole 233, and the first hollow groove 2341 and the second hollow groove 2342 are alternately spaced along the circumference of the first connecting portion 231.

[0138] The number of the first hollow groove 2341 can be one or more. The number of the second hollow groove 2342 can be one or more. The number of the first hollow groove 2341 can be equal to the number of the second hollow groove 2342 or different from the number of the second hollow groove 2342.

[0139] In some embodiments, there are multiple first hollow grooves 2341 , and among the multiple first hollow grooves 2341 , at least two first hollow grooves 2341 are located on opposite sides of the through hole 233 , and the extension directions of the two first hollow grooves 2341 are opposite.

[0140] In some embodiments, there are multiple second hollow grooves 2342 , and among the multiple second hollow grooves 2342 , at least two second hollow grooves 2342 are located on opposite sides of the through hole 233 , and the extension directions of the two second hollow grooves 2342 are opposite.

[0141] For example, the number of first hollow grooves 2341 can be two, and the number of second hollow grooves 2342 can be two. The two first hollow grooves 2341 are located on opposite sides of the through hole 233 and extend in a direction away from each other. The two second hollow grooves 2342 are located on opposite sides of the through hole 233 and extend in a direction away from each other. In one example, the two first hollow grooves 2341 and the two second hollow grooves 2342 can form a cross-like shape. That is, the line connecting the centers of the two first hollow grooves 2341 can be perpendicular to the line connecting the centers of the two second hollow grooves 2342. In this way, when the air pressure inside the cylindrical battery cell reaches a certain threshold, the two connected first hollow grooves 2341 are more likely to rupture, providing a better pressure relief channel for the cylindrical battery cell. The two unconnected second hollow grooves 2342 are less likely to rupture, so that the first connecting portion 231 still has a certain structural strength, so that a stable electrical connection is formed between the first connecting portion 231 and the first tab 212a.

[0142] In the above technical solution, both the exhaust channel area and the structural strength of the current collecting member 23 can be taken into consideration, thereby ensuring the stability of the cylindrical battery cell in use to a certain extent.

[0143] According to some embodiments of the present application, the hollow grooves 234 and the first notches 231 a are alternately arranged along the circumference of the first connecting portion 231 .

[0144] In other words, the first notch 231a can be directly opposite the area between two adjacent hollow grooves 234. In this way, the shortest distance between the first notch 231a and the hollow groove 234 is larger, which can to some extent avoid the problem of the area between the first notch 231a and the hollow groove 234 being easily cracked due to the distance between the first notch 231a and the hollow groove 234 being too small.

[0145] It is understandable that the alternating arrangement of the hollow grooves 234 and the first notches 231a referred to here does not only include the alternating arrangement of one hollow groove 234 and one first notch 231a, that is, the hollow grooves 234 and the first notches 231a may not have a one-to-one correspondence.

[0146] In some embodiments, the number of hollow grooves 234 can be greater than the number of first notches 231a, so that one hollow groove 234 can be separated between two adjacent first notches 231a, and multiple hollow grooves 234 can be separated between two adjacent first notches 231a in the remaining part; or, multiple hollow grooves 234 can be separated between every two adjacent first notches 231a.

[0147] In other embodiments, the number of hollow grooves 234 may be less than the number of first notches 231a, so that one first notch 231a may be spaced between two adjacent hollow grooves 234, and multiple first notches 231a may be spaced between two adjacent hollow grooves 234; or, multiple first notches 231a may be spaced between every two adjacent hollow grooves 234.

[0148] In some other embodiments, the number of the hollow grooves 234 is the same as the number of the first notches 231 a , and the hollow grooves 234 and the first notches 231 a may be alternately arranged one by one.

[0149] In the above technical solution, a certain distance can be maintained between the hollow groove 234 and the first notch 231a, so that the first connecting portion 231 has a certain strength. When the pressure inside the cylindrical battery cell is normal, the current collecting member 23 can form a stable electrical connection with the electrode assembly 21 and the shell 22.

[0150] Continue to refer Figures 8 to 12 According to some embodiments of the present application, the first connection portion 231 further includes: at least one positioning hole 235 , which passes through the first connection portion 231 along the thickness direction of the first connection portion 231 and is spaced apart from the through hole 233 .

[0151] When the second connection portion 232 is welded to the inner wall of the housing 22, a welding device can be used to weld the second connection portion 232 and the housing 22. When the current collecting member 23 is located in the housing 22 and the second connection portion 232 contacts the inner wall of the housing 22, the welding device welds the contact position between the outer periphery of the second connection portion 232 and the inner wall of the housing 22.

[0152] The welding device includes a welding head for emitting welding energy toward the second connecting portion 232 and the inner wall of the housing 22. The welding head needs to be aligned with the connection between the outer periphery of the second connecting portion 232 and the inner wall of the housing 22, and then welded at that connection. In other words, when the welding device is welding the second connecting portion 232 to the housing 22, the welding head needs to be aligned with the outer periphery of the second connecting portion 232.

[0153] The welding device can have a reference portion corresponding to the positioning hole 235. When the welding device welds the current collecting component 23, it only needs to align the positioning hole 235 with the reference portion of the welding device to align the welding head of the welding device with the outer periphery of the second connecting portion 232, thereby quickly locating the welding position of the second connecting portion 232 and the inner wall of the shell 22.

[0154] In some embodiments, the alignment of the positioning hole 235 with the reference portion can be that the positioning hole 235 is directly opposite to the reference portion but not in contact with the reference portion. In other embodiments, the alignment of the positioning hole 235 with the reference portion can also be that the positioning hole 235 is fixed to the reference portion.

[0155] In some embodiments, the number of the positioning hole 235 may be 1. In other embodiments, the number of the positioning holes 235 may also be multiple, for example, 2, 3 or more.

[0156] In some embodiments, the positioning hole 235 may be in communication with the hollow groove 234 , for example, may be in communication with the end of the second hollow groove 2342 away from the through hole 233 .

[0157] In other embodiments, the positioning hole 235 may not be connected to the hollow groove 234 .

[0158] In the above technical solution, by providing the positioning hole 235 , the position where the current collecting component 23 is docked with the electrode assembly 21 and the shell 22 can be quickly located during the process of installing the current collecting component 23 into the shell 22 , which is beneficial to improving the preparation efficiency of cylindrical battery cells and increasing production capacity.

[0159] According to some embodiments of the present application, the shell 22 includes a side wall, the inner wall surface of the side wall is parallel to the winding axis of the electrode assembly 21, and the second connecting portion 232 is welded to the inner wall surface of the side wall.

[0160] The second connection portion 232 may be connected to the inner wall surface of the side wall by methods including but not limited to laser welding, ultrasonic welding or friction welding.

[0161] For example, the second connection portion 232 and the inner wall surface of the side wall can be welded by any method such as internal welding or external welding to meet different welding requirements, which is conducive to ensuring welding quality.

[0162] Internal welding refers to the process whereby a laser is emitted from the interior of the shell 22 and penetrates the second connecting portion 232 in a direction intersecting the winding axis of the electrode assembly 21 to form a welded portion with the sidewall. For example, the laser can be emitted in a direction perpendicular to the winding axis of the electrode assembly 21 to the second connecting portion 232. After the laser penetrates the second connecting portion 232, it is projected onto the shell 22, causing the second connecting portion 232 to be welded to the shell 22 to form a welded portion. When internal welding is used, the laser is emitted toward the outside of the shell 22, which can prevent the laser from being emitted toward the electrode assembly during welding, thereby preventing damage to the electrode and improving the safety of the welding operation.

[0163] External welding involves irradiating the laser from the outside of the housing 22 toward the inside, penetrating the second connection portion 232 in a direction intersecting the winding axis of the electrode assembly 21, and forming a weld with the sidewall. External welding provides ample space for the laser to be positioned outside the battery, improving the precision of the laser welding and, consequently, the quality of the weld.

[0164] The first connection portion 231 and the second connection portion 232 are not arranged on the same plane, so that the fusion portion formed by welding the second connection portion 232 and the inner wall surface of the side wall and the connection position of the first connection portion 231 and the first electrode tab 212a are located in different directions to avoid mutual influence during welding.

[0165] In the above technical solution, the connection strength between the second connecting portion and the side wall can be improved, and a certain exhaust space can be enclosed on the side of the first connecting portion close to the second connecting portion, further improving the exhaust efficiency of the cylindrical battery cell.

[0166] refer to Figure 5 According to some embodiments of the present application, the cylindrical battery cell further includes: an electrode terminal 214, which is insulated and connected to the shell 22; wherein the electrode assembly 21 includes a second electrode tab 212b with a different polarity from the first electrode tab 212a, and the second electrode tab 212b is electrically connected to the electrode terminal 214.

[0167] The first electrode tab 212a may be a positive electrode tab, and the second electrode tab 212b may be a negative electrode tab. Alternatively, the first electrode tab 212a may be a negative electrode tab, and the second electrode tab 212b may be a positive electrode tab.

[0168] The insulated connection between the electrode terminal 214 and the housing 22 means that the electrode terminal 214 can be fixed to the housing 22 but is insulated from the housing 22 to reduce the risk of short circuits. In some embodiments, an insulating member can be provided inside the housing 22 to isolate the electrode terminal 214 from the housing 22. Exemplarily, the insulating member can be made of plastic, rubber, etc.

[0169] refer to Figure 5 、 Figure 7 as well as Figure 13 In some embodiments, the cylindrical battery cell further includes a current collecting plate 215 , which is located at one end of the housing 22 away from the current collecting member 23 .

[0170] The current collecting plate 215 can be electrically connected to the second electrode tab 212b and insulated from the housing 22 to reduce the risk of short circuits. The current collecting plate 215 can be electrically connected to the second electrode tab 212b by welding, such as laser welding, ultrasonic welding, or friction welding. The second electrode tab 212b can be electrically connected to the electrode terminal 214 through the current collecting plate 215.

[0171] In some embodiments, the cylindrical battery cell may further include a cover plate 26, which is located on the side of the current collecting plate 215 away from the electrode assembly 21 and covers the opening of the housing 22 away from the current collecting member 23. In some embodiments, the cover plate 26 may have a liquid injection port for injecting electrolyte, such as battery electrolyte, into the interior of the cylindrical battery cell. The cover plate 26 may also have an aluminum nail 261 and a plastic nail 262 for sealing the liquid injection port. The plastic nail 262 is mounted on the outside of the aluminum nail 261 and is fixedly connected to the aluminum nail 261 as a whole.

[0172] In the above technical solution, the tabs with different polarities can effectively maintain a stable circuit state between the positive and negative electrodes of the cylindrical battery cell, so that the cylindrical battery cell can work normally.

[0173] An embodiment of the present application provides a battery, which includes the cylindrical battery cell in the above embodiment.

[0174] For the structures of the battery and cylindrical battery cells, reference may be made to the relevant descriptions in the above embodiments.

[0175] In the above technical solution, since the exhaust efficiency of the cylindrical battery cells can be improved, the reliability of the battery is improved.

[0176] An embodiment of the present application provides an electrical device, which includes the battery in the above embodiment.

[0177] The battery is used to provide electrical energy to the electrical device. For the description of the electrical device, please refer to the relevant description in the above embodiments.

[0178] The present application embodiment provides a cylindrical battery cell, referring to Figures 3 to 6 as well as Figure 10 Learn Figure 13The cylindrical battery cell includes: an electrode assembly 21 having a wound structure and including a first electrode tab 212a; a housing 22 defining a space for accommodating the electrode assembly 21; and a current collecting member 23 including a first connecting portion 231 and a second connecting portion 232 connected thereto. The second connecting portion 232 is connected to the outer edge of the first connecting portion 231 and protrudes away from the electrode assembly 21, and is perpendicular to the first connecting portion 231. The first connecting portion 231 is electrically connected to the first electrode tab 212a, and the second connecting portion 232 is directly connected to the housing 22. The first connecting portion 231 has a plurality of first notches 231a recessed from its outer edge toward the center. The first notches 231a connect the spaces on both sides of the first connecting portion 231 along its thickness. There are multiple second connection parts 232 , which are arranged at intervals along the outer periphery of the first connection part 231 . Second gaps 232 a are formed between adjacent second connection parts 232 , and the second gaps 232 a are connected to the first gaps 231 a .

[0179] The number of the first notches 231 a and the second notches 232 a are multiple and equal, and the multiple first notches 231 a and the multiple second notches 232 a are arranged in a one-to-one correspondence.

[0180] The first connection portion 231 further includes a through hole 233 , which is correspondingly disposed and communicated with the central hole 213 of the electrode assembly 21 .

[0181] The first connection portion 231 further includes a first hollow groove 2341 and a second hollow groove 2342 arranged along the circumference of the through hole 233 , and either one of the first hollow groove 2341 and the second hollow groove 2342 extends in a direction away from the through hole 233 .

[0182] The first hollow groove 2341 is connected to the through hole 233, and the second hollow groove 2342 is spaced apart from the through hole 233. There are two first hollow grooves 2341, and the two first hollow grooves 2341 extend in opposite directions. There are also two second hollow grooves 2342, and the two second hollow grooves 2342 extend in opposite directions.

[0183] The first hollow groove 2341 and the second hollow groove 2342 are spaced apart from the first notch 231 a along the circumferential direction of the first connecting portion 231 .

[0184] The first connection portion 231 further includes two positioning holes 235 , which are respectively connected to ends of the two second hollow grooves 2342 away from the through hole 233 .

[0185] The cylindrical battery cell further includes an electrode terminal 214 insulated and connected to the housing 22 . The electrode assembly 21 includes a second electrode tab 212 b having a different polarity from the first electrode tab 212 a . The second electrode tab 212 b is connected to the electrode terminal 214 .

[0186] The cylindrical battery cell further includes a current collecting plate 215 , which is located at one end of the housing 22 away from the current collecting member 23 .

[0187] The current collecting plate 215 is electrically connected to the second electrode tab 212 b by welding and is insulated from the housing 22 .

[0188] The cylindrical battery cell also includes a cover plate 26, which is located on the side of the current collecting plate 215 away from the electrode assembly 21 and covers the opening of the housing 22 away from the current collecting member 23. The cover plate 26 has a liquid injection port and an aluminum nail 261 and a plastic nail 262 that seal the liquid injection port. The plastic nail 262 is mounted outside the aluminum nail 261 and is fixed to the aluminum nail 261 as a whole.

[0189] 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: The electrode assembly is a wound structure, and the electrode assembly includes a first electrode tab; a housing defining an accommodation space for accommodating the electrode assembly; as well as The current collecting component includes a first connecting portion and a second connecting portion connected to each other, the second connecting portion is connected to the outer edge of the first connecting portion and protrudes in the direction away from the electrode assembly, the first connecting portion is electrically connected to the first electrode tab, and the second connecting portion is directly connected to the shell, and the first connecting portion has at least one first notch recessed from its outer edge toward the center, and the first notch is used to connect the space on both sides of the first connecting portion along its thickness direction.

2. The cylindrical battery cell according to claim 1, characterized in that: Also includes: an end cap, located on a side of the current collecting member away from the electrode assembly and connected to the housing to close the opening of the accommodating space; The end cover is provided with a pressure relief component, which is spaced apart from the first connecting portion and is configured to break when the internal pressure of the battery cell reaches a preset threshold.

3. The cylindrical battery cell according to claim 1, characterized in that: There are multiple second connection parts, and the multiple second connection parts are arranged at intervals along the outer periphery of the first connection part, and second gaps are formed between adjacent second connection parts.

4. The cylindrical battery cell according to claim 3, characterized in that: The first notch and the second notch are communicated with each other.

5. The cylindrical battery cell according to claim 4, characterized in that: The number of the first notches and the number of the second notches are multiple and equal, and the multiple first notches and the multiple second notches are arranged in a one-to-one correspondence.

6. The cylindrical battery cell according to any one of claims 1 to 5, characterized in that: The shell includes a side wall, and on a projection plane perpendicular to the winding axis of the electrode assembly, an orthographic projection of a gap between the electrode assembly and an inner wall surface of the side wall at least partially overlaps with an orthographic projection of the first notch.

7. The cylindrical battery cell according to any one of claims 1 to 5, characterized in that: The electrode assembly also includes a main body, the first tab is located at the end of the main body along the winding axis of the electrode assembly, and the maximum diameter of the first connecting portion is less than or equal to the inner diameter of the shell and greater than the diameter of the main body.

8. The cylindrical battery cell according to any one of claims 1 to 5, characterized in that: The first connecting portion further includes: A through hole is arranged opposite to and communicated with the central hole of the electrode assembly.

9. The cylindrical battery cell according to claim 8, characterized in that: The first connecting portion further includes: A plurality of hollow grooves are arranged at intervals along the circumference of the through hole, and any one of the plurality of hollow grooves extends in a direction away from the through hole.

10. The cylindrical battery cell according to claim 9, characterized in that: At least one of the plurality of hollow grooves is communicated with the through hole.

11. The cylindrical battery cell according to claim 9, characterized in that: The multiple hollow grooves include at least one first hollow groove and at least one second hollow groove, the first hollow groove is connected to the through hole, the second hollow groove is spaced apart from the through hole, and the first hollow groove and the second hollow groove are alternately spaced along the circumference of the first connecting portion.

12. The cylindrical battery cell according to claim 9, characterized in that: The hollow grooves and the first notches are alternately arranged along the circumference of the first connecting portion.

13. The cylindrical battery cell according to claim 9, characterized in that: The first connection portion further includes: at least one positioning hole, which passes through the first connection portion along a thickness direction of the first connection portion and is spaced apart from the through hole.

14. The cylindrical battery cell according to any one of claims 1 to 5, characterized in that: The shell includes a side wall, an inner wall surface of the side wall is parallel to the winding axis of the electrode assembly, and the second connecting portion is welded to the inner wall surface of the side wall.

15. The cylindrical battery cell according to any one of claims 1 to 5, characterized in that: Also includes: an electrode terminal, insulated and connected to the housing; The electrode assembly includes a second electrode tab having a different polarity from the first electrode tab, and the second electrode tab is electrically connected to the electrode terminal.

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

17. An electrical device, characterized in that: Comprising the battery of claim 16.

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