Cylindrical batteries and electrical devices

Abstract

This application discloses a cylindrical battery and an electrical device, relating to the field of battery technology. The cylindrical battery includes a casing, a core, and an insulating component. The casing includes a cylindrical body and a base plate, with the base plate covering the end of the cylindrical body. The core is disposed within the cylindrical body and includes multiple negative electrode tabs arranged in multiple layers along the radial direction of the core. The insulating component is disposed between the core and the base plate, and has openings. The multiple negative electrode tabs pass through these openings and are bent towards the axis of the core, electrically connected to the base plate. The cylindrical battery provided in this application achieves direct cell connection to the base plate by bending the negative electrode tabs after passing them through the insulating sheet and using ultrasonic welding or resistance welding. This simplifies the production process, eliminates the use of current collectors, and effectively reduces cell manufacturing costs.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a cylindrical battery and an electrical device. Background Technology

[0002] Currently, the positive and negative electrode structure design of cylindrical batteries generally adopts a multi-tab welding method. This involves placing multiple metal tabs at both ends of the electrode sheet, connecting these tabs in parallel via ultrasonic welding or laser welding, and then further welding them to the current collector. As a key component for current conduction, the current collector is ultimately fixed to the battery top cover or casing by mechanical riveting or welding, forming a complete current path.

[0003] However, this structure requires two separate processes: tab-to-tab welding and tab-to-current collector welding, involving multiple steps such as precise positioning, energy parameter adjustment, and quality inspection. The more tabs there are, the more complex the welding fixtures become, and the higher the risk of quality issues such as incomplete welds and over-welding, leading to a decrease in overall yield and an increase in production cycle time. Utility Model Content

[0004] In view of this, this application provides a cylindrical battery and an electrical device, with the aim of solving one of the technical problems in the prior art.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows: In a first aspect, this application provides a cylindrical battery, comprising: The shell includes a cylindrical body and a bottom plate, the bottom plate covering the end of the cylindrical body; A core is disposed within the cylinder, and the core includes multiple negative electrode tabs, which are distributed in multiple layers in the radial direction of the core. An insulating element is disposed between the winding core and the base plate. An opening is formed on the insulating element, and a plurality of negative electrode tabs are inserted through the opening and bent toward the axis of the winding core. The negative electrode tabs are electrically connected to the base plate.

[0006] In an optional embodiment, the core has a central hole, and the base plate has a welding area, the projection of which falls into the central hole along the axial direction of the core.

[0007] In an optional embodiment, the projection of each negative electrode tab covers the central hole along the axial direction of the winding core; and / or The diameter of the central hole is R, the width of the negative electrode tab is W, and L satisfies: W > R.

[0008] In an optional embodiment, the welding area is circular, the welding area and the central hole are coaxially arranged, and the diameter of the welding area is S, satisfying: R / 2 < S < R.

[0009] In an optional implementation, the core diameter is D and the negative electrode tab length is L, satisfying: D / 2 < L < D.

[0010] In an optional embodiment, on the side of the winding core near the insulator, the center of each negative electrode tab forms a line with the center of the central hole, and multiple such lines form a fan-shaped area. In the axial direction of the core, the projection of the sector region lies within the opening.

[0011] In an optional embodiment, the sector region has an angle α connected to the central axis of the core, satisfying: 0°≤α≤120°.

[0012] In an optional implementation, when 0°≤α≤5°, the diameter of the negative electrode tab closest to the center hole in the radial direction of the core is R1, satisfying: R1>R, and 2L-D<R1<2L-R; In the radial direction of the core, the diameter at the negative electrode tab furthest from the central hole is R2, satisfying: R1 < R2 < D, and 2L-D < R2 < 2L-R.

[0013] In optional embodiments, the negative electrode tab is rectangular, trapezoidal, or parallelogram in shape; and / or In the unfolding direction of the core, the distance between two adjacent negative electrode tabs gradually increases in the direction away from the beginning of the core.

[0014] Secondly, this application provides an electrical device including the cylindrical battery in any of the above embodiments.

[0015] Compared to existing technologies, the advantages of this application are as follows: This application proposes a cylindrical battery, including a casing, a core, and an insulating component. The casing includes a cylindrical body and a base plate, with the base plate covering the end of the cylindrical body. The core is disposed within the cylindrical body and includes multiple negative electrode tabs distributed in multiple layers along the radial direction of the core. The insulating component is disposed between the core and the base plate, and has openings. The multiple negative electrode tabs pass through the openings and are bent towards the axis of the core, electrically connected to the base plate. Compared to the structure in related technologies where the negative electrode tabs are electrically connected to the battery casing via a current collector, the negative electrode tabs in this application are bent after passing through the insulating sheet and directly connected to the base plate via ultrasonic welding or resistance welding. This reduces the welding process of the negative electrode tabs, simplifying the production process; it eliminates the use of current collectors, effectively reducing the manufacturing cost of the battery cell; furthermore, the structural design of welding the negative electrode tabs to the base plate is particularly suitable for automated production, significantly improving production efficiency. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 The following are schematic diagrams of the cylindrical battery structure in some embodiments of this application; Figure 2 The following are schematic diagrams of the core structure in some embodiments of this application; Figure 3 This application shows one of the structural schematic diagrams of the end of a cylindrical battery in some embodiments; Figure 4 The following are schematic diagrams illustrating the structure of the core end in some embodiments of this application; Figure 5 This is shown as a second schematic diagram of the structure of the end of a cylindrical battery in some embodiments of this application.

[0018] Explanation of main component symbols: 100-cylindrical battery; 110-casing; 111-cylinder; 112-base plate; 120-core; 121-negative electrode tab; 122-positive electrode tab; 130-insulator; 131-opening; 123-center hole; 1121-welding area; 124-sector area. Detailed Implementation

[0019] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0020] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0022] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0024] Currently, multi-tab battery cores typically have multiple tabs on both the positive and negative electrodes, which are interconnected using resistance welding or ultrasonic welding. The positive tab is then electrically connected to the battery cap via a current collector, while the negative tab is electrically connected to the battery casing via the current collector. This structure increases the number of manufacturing steps and production costs.

[0025] In response to the above problems, such as Figure 1 As shown, an embodiment of this application provides a cylindrical battery 100. The cylindrical battery 100 includes a casing 110, a winding core 120, and an insulating member 130.

[0026] The shell 110 includes a cylinder 111 and a bottom plate 112, with the bottom plate 112 covering the end of the cylinder 111.

[0027] The housing 110 is typically made of nickel-plated steel (such as 18650) or high-nickel steel or aluminum alloy.

[0028] The base plate 112 is usually a closed steel shell bottom, integrally formed with the shell 110, and must be flat to fit the battery holder.

[0029] The core 120 is disposed inside the cylinder 111. The core 120 includes multiple negative electrode tabs 121, which are distributed in multiple layers in the radial direction of the core 120.

[0030] like Figure 2 As shown in this application, the core 120 adopts a double-ended tab design, with the positive tab 122 and the negative tab 121 located at opposite ends of the core 120. This structure can improve current conduction efficiency and reduce internal resistance, and is especially suitable for high-power or large-capacity batteries.

[0031] The negative electrode tab 121 is fully extended from the lower end of the core 120 (near the bottom plate 112 of the housing 110) and welded to the housing 110.

[0032] like Figure 1 An insulating component 130 is disposed between the core 120 and the base plate 112. The insulating component 130 is used to prevent short circuit caused by contact between the electrode tab and the core 120. The cylinder 111 is provided with an inwardly recessed groove, and the edge of the insulating component 130 is engaged with the groove of the cylinder 111 for locking and fixing.

[0033] See also Figure 1 and Figure 3An opening 131 is formed on the insulating component 130, through which multiple negative electrode tabs 121 pass and bend towards the axis of the core 120, so that all negative electrode tabs 121 are stacked together, reducing the number of welding steps. The negative electrode tabs 121 are electrically connected to the base plate. Compared with the structure in related technologies where the negative electrode tabs 121 are electrically connected to the battery casing through a current collector, the negative electrode tabs 121 of this application are bent after passing through the insulating sheet and are directly connected to the base plate 112 by ultrasonic welding or resistance welding. This reduces the welding process of the negative electrode tabs 121, simplifying the production process; it eliminates the use of current collectors, effectively reducing the manufacturing cost of the battery cell; in addition, the structural design of welding the negative electrode tabs 121 and the base plate 112 is particularly suitable for automated production modes, which can significantly improve production efficiency.

[0034] In some embodiments, such as Figure 3 and Figure 4 As shown, the core 120 has a central hole 123, and the base plate 112 has a welding area 1121. In the axial direction of the core 120, the projection of the welding area 1121 falls into the central hole 123.

[0035] The core 120 is a structure formed by winding around the central axis, with a hollow area (central hole 123) inside, which is often used to insert the mandrel, heat pipe or facilitate subsequent assembly.

[0036] Projecting downwards along the axial direction (i.e., the winding axis direction) of the core 120, the welding area 1121 is entirely within the area of ​​the central hole 123. Placing the welding area 1121 within the central hole 123 effectively saves space in the base plate 112, contributing to a more compact overall battery structure and improving energy density. Furthermore, the central hole 123 and the welding area 1121 are easier to align, facilitating precise positioning by automated equipment (such as laser welding heads). Since welding occurs in the central region, it may contribute to a more uniform heat distribution, reducing structural damage caused by localized thermal stress.

[0037] In some embodiments, such as Figure 3 and Figure 5 As shown, the projection of each negative electrode tab 121 covers the central hole 123 along the axial direction of the core 120. Arranging the negative electrode tabs 121 within the range of the central hole 123 can effectively save space in the base plate 112, which helps to make the overall structure of the cylindrical battery 100 more compact and improves energy density; it also makes it easier to align multiple negative electrode tabs 121, which is convenient for precise positioning by automated equipment (such as laser welding heads); the welding occurs at the central hole 123, so that the welding position is located in the middle of the base plate 112, which may help to distribute heat more evenly and reduce structural damage caused by local thermal stress.

[0038] In some embodiments, such as Figure 3As shown, the diameter of the central hole 123 is R, and the width of the negative electrode tab 121 is W, satisfying that W > R. This ensures that the projection of each negative electrode tab 121 can cover the central hole 123 along the axial direction of the core 120.

[0039] In one embodiment, such as Figure 3 As shown, the welding area 1121 is circular, and the welding area 1121 and the center hole 123 are coaxially arranged to facilitate precise positioning by automated equipment (such as laser welding heads).

[0040] In other embodiments, the shape of the welding area 1121 can also be square, hexagonal, etc., without limitation.

[0041] like Figure 3 As shown, the diameter of the welding area 1121 is S, satisfying: R / 2 < S < R. Along the axial direction of the core 120, the projected area of ​​the welding area 1121 occupies more than one-quarter of the area of ​​the central hole 123. By arranging the welding area 1121 within the range of the central hole 123 and occupying a large proportion of the area, the welding area is increased, the occurrence of incomplete welds is reduced, electrical connections are achieved more effectively, and the electrical performance and reliability of the battery are improved.

[0042] In some embodiments, such as Figure 2 and Figure 4 As shown, the diameter of the core 120 is D, and the length of the negative electrode tab 121 is L, satisfying: D / 2 < L < D. The length of the negative electrode tab 121 is set between D / 2 and D, making it long enough to facilitate welding operations while avoiding structural interference problems caused by excessive length. An appropriately long negative electrode tab 121 is easier to align, facilitating precise positioning by automated equipment (such as laser welding heads), allowing welding to occur in the area of ​​the central hole 123. This may help to distribute heat more evenly, reduce structural damage caused by localized thermal stress, and improve the electrical performance and reliability of the battery.

[0043] In some embodiments, such as Figure 4 As shown, on the side of the core 120 near the insulator 130, the center of each negative electrode tab 121 and the center of the center hole 123 form a line, and multiple lines form a fan-shaped area 124. When the alignment of multiple negative electrode tabs 121 in the radial direction of the core 120 is good, the area of ​​the fan is small; otherwise, the area of ​​the fan is large.

[0044] In the axial direction of the core 120, the projection of the fan-shaped region 124 is located within the opening 131, so that all negative electrode tabs 121 can pass through the opening 131, reducing soldering omissions.

[0045] In some embodiments, such as Figure 4As shown, the sector region 124 has an angle α connected to the central axis of the core 120, which satisfies: 0°≤α≤120°. By controlling the angle of the sector region 124, multiple negative electrode tabs 121 can overlap, and the overlapping area covers the welding area 1121, thereby improving welding efficiency and welding quality.

[0046] In this application, the number of negative electrode tabs 121 is 6-22, and can be set to other numbers as needed without limitation. The negative electrode tabs 121 are distributed in the continuous winding layer.

[0047] In some embodiments, such as Figure 5 As shown, when 0°≤α≤5°, the alignment of the multilayer negative electrode tabs 121 is good. In the radial direction of the core 120, the diameter of the negative electrode tab 121 closest to the center hole 123 is R1, satisfying: R1>R, and 2L-D<R1<2L-R. This ensures that the innermost negative electrode tabs 121 can cover the center hole 123 without exceeding the range of the core 120, allowing for better alignment between the innermost negative electrode tabs 121 and the center hole 123, improving welding quality, reducing the occurrence of incomplete welds, reducing the size of the base plate 112, and increasing the energy density of the battery.

[0048] In the radial direction of the core 120, the diameter of the negative electrode tab 121 furthest from the center hole 123 is R2, satisfying: R1<R2<D, and 2L-D<R2<2L-R, so that the outermost negative electrode tab 121 covers the center hole 123 and does not exceed the range of the core 120, so that the outermost negative electrode tab 121 can be better aligned with the center hole 123, effectively saving space in the base plate 112, reducing the size of the base plate 112, and improving the energy density of the battery.

[0049] In some embodiments, the negative electrode tab 121 is rectangular, trapezoidal, or parallelogram in shape.

[0050] In some embodiments, in the unfolding direction of the core 120, the spacing between two adjacent negative electrode tabs 121 gradually increases in the direction away from the beginning of the core 120. The gradually increasing spacing can better balance the current distribution, reduce the problems of local overheating and uneven electrochemical reaction; the gradually increasing spacing helps to avoid mechanical stress concentration caused by overly dense tabs, and improve the stability of the overall structure.

[0051] This application also provides an electrical device, including the cylindrical battery 100 in any of the above embodiments, and therefore has all the beneficial effects of the cylindrical battery 100 in any of the above embodiments, which will not be described in detail here.

[0052] It should be noted that the electrical device can be a vehicle, mobile phone, portable device, laptop, electric toy, and power tool, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application does not impose any special limitations on the above-mentioned electrical devices.

[0053] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0054] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A cylindrical battery, characterized by comprising: include: The shell includes a cylindrical body and a bottom plate, the bottom plate covering the end of the cylindrical body; A core is disposed within the cylinder, and the core includes multiple negative electrode tabs, which are distributed in multiple layers in the radial direction of the core. An insulating element is disposed between the winding core and the base plate. An opening is formed on the insulating element, and a plurality of negative electrode tabs are inserted through the opening and bent toward the axis of the winding core. The negative electrode tabs are electrically connected to the base plate.

2. The cylindrical battery according to claim 1, characterized in that, The core has a central hole, and the base plate has a welding area. The projection of the welding area onto the axial direction of the core falls into the central hole.

3. The cylindrical battery according to claim 2, characterized in that, Along the axial direction of the winding core, the projection of each negative electrode tab covers the central hole; and / or The diameter of the central hole is R, and the width of the negative electrode tab is W, satisfying that W > R.

4. The cylindrical battery according to claim 3, characterized in that, The welding area is circular, and the welding area and the central hole are coaxially arranged. The diameter of the welding area is S, which satisfies: R / 2 < S < R.

5. The cylindrical battery according to claim 3, characterized in that, The core diameter is D, and the negative electrode tab length is L, satisfying: D / 2 < L < D.

6. The cylindrical battery according to claim 5, characterized in that, On the side of the winding core near the insulator, the center of each negative electrode tab forms a line with the center of the central hole, and multiple such lines form a fan-shaped area; In the axial direction of the core, the projection of the sector region lies within the opening.

7. The cylindrical battery according to claim 6, characterized in that, The sector region has an angle α with the central axis of the core, satisfying: 0°≤α≤120°.

8. The cylindrical battery according to claim 7, characterized in that, When 0°≤α≤5°, the diameter of the negative electrode tab closest to the center hole in the radial direction of the core is R1, satisfying: R1>R, and 2L-D<R1<2L-R; In the radial direction of the core, the diameter at the negative electrode tab furthest from the central hole is R2, satisfying: R1 < R2 < D, and 2L-D < R2 < 2L-R.

9. The cylindrical battery according to any one of claims 1 to 8, characterized in that, The negative electrode tab is rectangular, trapezoidal, or parallelogram in shape; and / or In the unfolding direction of the core, the distance between two adjacent negative electrode tabs gradually increases in the direction away from the beginning of the core.

10. An electrical appliance, characterized in that, Includes the cylindrical battery as described in any one of claims 1 to 9.

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