Cylindrical battery, battery pack, and electrical device

Abstract

A cylindrical battery, a battery pack, and an electrical device. The cylindrical battery comprises a top cover and an explosion-proof plate. The top cover comprises a base body, a connecting portion, and an end portion. The end portion protrudes from the base body along an axial direction of the cylindrical battery. The connecting portion connects the end portion and the base body. At least a portion of the explosion-proof plate and the top cover are arranged along the axial direction. The base body comprises an extension portion and a press-down portion. The press-down portion is arranged on a side of the extension portion facing an axis of the cylindrical battery. The press-down portion protrudes from the extension portion towards the explosion-proof plate, and the press-down portion fits against the explosion-proof plate. By providing the press-down portion on the top cover of the cylindrical battery, when the explosion-proof plate flips and bursts under internal gas pressure of the battery, the press-down portion limits a flipping distance of the explosion-proof plate, which helps reduce the risk of excessive burst pressure or failure of the explosion-proof plate to burst and also helps reduce burst-pressure deviation, thereby improving the safety performance of the cylindrical battery.

Description

A cylindrical battery, a battery pack, and an electrical device.

[0001] This application claims priority to Chinese Patent Application No. 202411957648.8, filed on December 27, 2024, entitled "A Cylindrical Battery, Battery Pack and Power-Using Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of energy storage technology, and in particular to a cylindrical battery, battery pack and power supply device. Background Technology

[0003] Cylindrical batteries, such as lithium-ion batteries, have the characteristics of high specific energy, high operating voltage, low self-discharge rate, small size, and light weight, and are widely used in a variety of fields.

[0004] Cylindrical batteries typically have a CID (current interrupt device), which includes a rupture disc. When a cylindrical battery malfunctions or experiences excessive internal pressure, the rupture disc flips and bursts to cut off power and release pressure, thus improving the battery's safety. However, during flipping and bursting, there is a risk that the rupture disc may flip too far, resulting in excessive burst pressure or failing to burst at all. Summary of the Invention

[0005] The purpose of this application is to provide a cylindrical battery, battery pack, and power supply device that helps reduce the risk of excessive flipping distance of the explosion-proof sheet or failure to explode, thereby improving the safety performance of the cylindrical battery.

[0006] It should be noted that while this application uses lithium-ion batteries as an example of cylindrical batteries to explain the invention, the cylindrical batteries in this application are not limited to lithium-ion batteries. The specific technical solution is as follows:

[0007] This application provides a cylindrical battery, including a top cover and an explosion-proof sheet. The top cover includes a base, a connecting portion, and an end portion. The end portion protrudes from the base along the axial direction of the cylindrical battery, and the connecting portion connects the end portion and the base. At least a portion of the explosion-proof sheet and the top cover are arranged axially. The base includes an extension portion and a pressing portion. The pressing portion is disposed on the side of the extension portion facing the axis of the cylindrical battery, and protrudes from the extension portion towards the explosion-proof sheet, fitting against the explosion-proof sheet. By providing a pressing portion in the top cover of the cylindrical battery, when an anomaly occurs inside the battery and the internal air pressure is too high, the pressing portion limits the flipping distance of the explosion-proof sheet when it flips and bursts under the action of the internal air pressure. This helps to reduce the risk of excessive burst pressure or failure to burst, and helps to reduce the deviation of burst pressure, thereby improving the safety performance of the cylindrical battery. At the same time, it helps to provide a larger housing space for electrode components within the casing of the cylindrical battery, thereby increasing the volume of the electrode components and improving the energy density of the cylindrical battery.

[0008] In one or more embodiments, the extension includes a first portion and a second portion. Along the axial direction, the projection of the first portion surrounds the projection of the second portion, and a pressing portion protrudes from the second portion toward the explosion-proof sheet. The second portion protrudes away from the explosion-proof sheet relative to the first portion, forming a first space on the side of the second portion facing the explosion-proof sheet, with a portion of the explosion-proof sheet located in the first space. This arrangement facilitates providing a larger accommodating space for the electrode assembly within the cylindrical battery casing, thereby increasing the volume of the electrode assembly and improving the energy density of the cylindrical battery.

[0009] In one or more embodiments, the explosion-proof sheet includes a flip-up portion, a protrusion, and a fixing portion arranged radially along the cylindrical battery. The fixing portion is connected to the first portion, and at least a portion of the protrusion is located in the first space. This arrangement facilitates providing a larger accommodating space for the electrode assembly within the cylindrical battery casing, thereby increasing the volume of the electrode assembly and improving the energy density of the cylindrical battery.

[0010] In one or more embodiments, the pressing portion is fitted to the protruding portion. This arrangement helps to reduce the flipping distance of the explosion-proof sheet, reducing the risk of excessive burst pressure or failure to burst, and minimizing burst pressure deviation, thereby improving the safety performance of the cylindrical battery.

[0011] In one or more embodiments, the flipping portion includes a groove along the axial direction, and the projection of the pressing portion is separate from the projection of the groove. In the radial direction of the cylindrical battery, the groove is closer to the axis of the cylindrical battery than the pressing portion. This arrangement helps reduce the risk of the vent plate failing to explode due to the pressing portion obstructing the groove, and also helps reduce the deviation of the burst pressure, thereby improving the safety performance of the cylindrical battery.

[0012] In one or more embodiments, the projection of the pressing portion overlaps with the projection of the flipping portion along the axial direction. This arrangement helps to reduce the flipping distance of the explosion-proof sheet, reducing the risk of excessive burst pressure or failure to burst, and minimizing burst pressure deviation, thereby improving the safety performance of the cylindrical battery.

[0013] In one or more embodiments, the protrusion forms a second space on the side facing away from the second portion; the cylindrical battery also includes a perforated plate and an insulating member, the perforated plate and the flip-over portion being electrically connected, and at least a portion of the insulating member being disposed between the perforated plate and the explosion-proof sheet along the axial direction, and located in the second space. This arrangement facilitates providing accommodating space for the insulating member, reduces the distance between the portion of the flip-over portion not electrically connected to the perforated plate and the perforated plate, provides greater accommodating space for the electrode assembly within the cylindrical battery casing, and facilitates increasing the volume of the electrode assembly and improving the energy density of the cylindrical battery.

[0014] In one or more embodiments, the insulating member includes a limiting portion disposed on the side of the perforated plate away from the axis of the cylindrical battery. This arrangement facilitates the insulating member in limiting the perforated plate radially within the cylindrical battery, thereby improving the positional stability of the perforated plate.

[0015] In one or more embodiments, the perforated plate includes a first surface facing the flipping portion, the first surface being flat. This arrangement helps to reduce the distance between the portion of the flipping portion not electrically connected to the perforated plate and the perforated plate, providing greater accommodating space for the electrode assembly within the cylindrical battery casing, thereby increasing the volume of the electrode assembly and improving the energy density of the cylindrical battery.

[0016] In one or more embodiments, along the circumference of the cylindrical battery, the pressing part includes multiple spaced pressing segments, the sum of the central angles corresponding to the multiple pressing segments being A, where 210°≤A≤270°. By adjusting A within the scope of this application, it is beneficial to disperse the stress on the pressing part, reduce the impact of the deformation of the pressing part on the explosion-proof sheet under harsh working conditions, make the explosion-proof sheet more uniformly stressed, and make the pressing part less prone to deformation. This helps to reduce the flipping distance of the explosion-proof sheet, reduce the risk of excessive burst pressure or failure to burst, and help to reduce the deviation of burst pressure, thereby improving the safety performance of the cylindrical battery.

[0017] In one or more embodiments, the connecting portion includes multiple spaced-apart connecting segments arranged axially, with the projections of the pressing segment and the connecting segments staggered around the axis of the cylindrical battery. This arrangement helps to disperse the stress in the pressing portion and the connecting portion, reduces the impact of deformation of the pressing portion and the connecting portion on each other under harsh operating conditions, helps to reduce the flipping distance of the explosion-proof sheet, reduces the deviation of the burst pressure, and thus improves the safety performance of the cylindrical battery.

[0018] A second aspect of this application provides a battery pack comprising a cylindrical battery according to any of the above embodiments.

[0019] A third aspect of this application provides an electrical device comprising a cylindrical battery or battery pack according to any of the above embodiments.

[0020] The beneficial effects of this application are:

[0021] This application provides a cylindrical battery, a battery pack, and an electrical device. The cylindrical battery includes a top cover and an explosion-proof sheet. The top cover includes a base, a connecting portion, and an end portion. The end portion protrudes from the base along the axial direction of the cylindrical battery, and the connecting portion connects the end portion and the base. At least a portion of the explosion-proof sheet and the top cover are arranged axially. The base includes an extension portion and a pressing portion. The pressing portion is disposed on the side of the extension portion facing the axis of the cylindrical battery, and protrudes from the extension portion towards the explosion-proof sheet, fitting against the explosion-proof sheet. By providing a pressing portion on the top cover of the cylindrical battery, when an anomaly occurs inside the battery and the internal air pressure is too high, the pressing portion limits the flipping distance of the explosion-proof sheet when it flips and bursts under the action of the internal air pressure. This helps reduce the risk of excessive burst pressure or failure to burst, reduces the deviation of burst pressure, and improves the safety performance of the cylindrical battery. Simultaneously, it allows for a larger space within the cylindrical battery casing for the electrode assembly, thereby increasing the volume of the electrode assembly and improving the energy density of the cylindrical battery.

[0022] Of course, implementing any product or method of this application does not necessarily require achieving all of the above advantages at the same time. Attached Figure Description

[0023] The accompanying drawings, which are provided to further illustrate this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application.

[0024] Figure 1 is a schematic diagram of the structure of a cylindrical battery according to one embodiment of this application;

[0025] Figure 2 is a partial cross-sectional view of the cylindrical battery shown in Figure 1.

[0026] Figure 3 is an enlarged view of A in Figure 2;

[0027] Figure 4 is a cross-sectional view of the top cover of the cylindrical battery shown in Figure 1.

[0028] Figure 5 is a schematic diagram of the explosion-proof sheet of the cylindrical battery shown in Figure 1;

[0029] Figure 6 is a cross-sectional view of the explosion-proof sheet shown in Figure 5;

[0030] Figure 7 is a cross-sectional view of the perforated plate of the cylindrical battery shown in Figure 1.

[0031] Figure 8 is a cross-sectional view of the insulating component of the cylindrical battery shown in Figure 1.

[0032] Figure 9 is a top view of the top cover of the cylindrical battery shown in Figure 1.

[0033] Figure 10 is a cross-sectional view of the top cover shown in Figure 9;

[0034] Figure 11 is a schematic diagram of the BB cross-sectional structure of the top cover shown in Figure 10;

[0035] Figure 12 is a schematic diagram of the battery pack provided in an embodiment of this application;

[0036] Figure 13 is a schematic diagram of the structure of the first type of electrical device provided in the embodiment of this application;

[0037] Figure 14 is a schematic diagram of the structure of the second type of electrical device provided in the embodiment of this application.

[0038] The reference numerals in the attached drawings are as follows: Top cover 110, base 111, extension 1111, first part 1111A, second part 1111B, pressing part 1112, pressing section 11121, connecting part 112, connecting section 1121, end 113, first distal end 113a, explosion-proof plate 120, flipping part 121, central region 1211, second surface 121a, groove 121A, protrusion 122, fixing part 123, third surface 123a, perforated plate 130, first surface 130a, second proximal end 130b, insulating part 140, limiting part 141, housing 150, side wall 151, protrusion 152, first proximal end 152a, electrode assembly 160; cylindrical battery 100, battery pack 200, power supply device 300. First space C, second space D, radial direction X, axial direction Y, axis L, circumferential direction R, center O. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention are within the scope of protection of this invention.

[0040] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. The term "and / or" as used herein includes any and all combinations of one or more of the related listed items.

[0041] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0042] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. Where there is no conflict, the various embodiments in this application can be combined with each other.

[0043] In related technologies, when the internal air pressure of a cylindrical battery reaches a threshold, the explosion-proof sheet may deform under localized stress, resulting in an excessively large flipping distance. This could lead to an excessively high pressure required for explosion or the battery failing to explode altogether, thus affecting the safety of the cylindrical battery.

[0044] This application provides a cylindrical battery, a battery pack, and an electrical device, with the main purpose of improving the safety of the cylindrical battery.

[0045] Figure 1 is a schematic diagram of the structure of a cylindrical battery according to one embodiment of this application. As shown in Figure 1, in a first aspect, this application provides a cylindrical battery 100, which can be a lithium-ion battery, sodium-ion battery, magnesium-ion battery, etc. The axis of the cylindrical battery 100 is L. The radial direction of the cylindrical battery 100 is X, which lies in a plane perpendicular to the axis L and is the direction from the axis L to the outer side of the cylindrical battery 100. The axial direction of the cylindrical battery 100 is Y, which is parallel to the axis L of the cylindrical battery 100.

[0046] Figure 2 is a partial cross-sectional view of the cylindrical battery shown in Figure 1. As shown in Figures 1 and 2, the first aspect of this application provides a cylindrical battery 100, which includes a top cover 110 and an explosion-proof sheet 120. The top cover 110 includes a base 111, a connecting portion 112, and an end portion 113. The end portion 113 protrudes from the base 111 along the axial direction Y of the cylindrical battery 100. The connecting portion 112 connects the end portion 113 and the base 111. At least a portion of the explosion-proof sheet 120 and the top cover 110 are disposed along the axial direction Y. The base 111 includes an extension portion 1111 and a pressing portion 1112. The pressing portion 1112 is disposed on the side of the extension portion 1111 facing the axis L of the cylindrical battery 100. The pressing portion 1112 protrudes from the extension portion 1111 towards the explosion-proof sheet 120 and fits against the explosion-proof sheet 120.

[0047] By providing a pressing part 1112 on the top cover 110 of the cylindrical battery 100, when an anomaly occurs inside the cylindrical battery 100 and the internal air pressure is too high, the pressing part 1112 limits the flipping distance of the explosion-proof sheet 120 under the action of the internal air pressure of the cylindrical battery 100. This helps to reduce the risk of excessive explosion pressure or failure to explode of the explosion-proof sheet 120, and helps to reduce the deviation of the explosion pressure, thereby improving the safety performance of the cylindrical battery 100. At the same time, since the pressing part 1112 limits and reduces the flipping distance of the explosion-proof sheet 120, it helps to provide a larger housing space for the electrode assembly 160 within the casing 150 of the cylindrical battery 100, thereby increasing the volume of the electrode assembly 160 and improving the energy density of the cylindrical battery 100.

[0048] Figure 3 is an enlarged view of A in Figure 2, and Figure 4 is a cross-sectional view of the top cover 110 of the cylindrical battery 100 shown in Figure 1. As shown in Figures 3 and 4, in one or more embodiments, the extension 1111 includes a first part 1111A and a second part 1111B. Along the axial direction Y, the projection of the first part 1111A surrounds the projection of the second part 1111B. The pressing part 1112 protrudes from the second part 1111B toward the explosion-proof sheet 120. The second part 1111B protrudes away from the explosion-proof sheet 120 relative to the first part 1111A, and a first space C is formed on the side of the second part 1111B facing the explosion-proof sheet 120. A portion of the explosion-proof sheet 120 is located in the first space C. With the above arrangement, it is beneficial to provide a larger accommodating space for the electrode assembly 160 within the casing 150 of the cylindrical battery 100, which is beneficial to increase the volume of the electrode assembly 160 and improve the energy density of the cylindrical battery 100.

[0049] Figure 5 is a structural schematic diagram of the explosion-proof sheet 120 of the cylindrical battery 100 shown in Figure 1, and Figure 6 is a cross-sectional structural schematic diagram of the explosion-proof sheet 120 shown in Figure 5. As shown in Figures 3, 5, and 6, in one or more embodiments, the explosion-proof sheet 120 includes a flipping portion 121, a protrusion 122, and a fixing portion 123 arranged along the radial direction X of the cylindrical battery 100. The fixing portion 123 is connected to the first portion 1111A, and at least a portion of the protrusion 122 is located in the first space C. With the above arrangement, it is beneficial to provide a larger accommodating space for the electrode assembly 160 within the housing 150 of the cylindrical battery 100, which is beneficial to increase the volume of the electrode assembly 160 and improve the energy density of the cylindrical battery 100.

[0050] In one or more embodiments, the pressing portion 1112 is attached to the side of the protrusion 122 near the axis L and the flipping portion 121 is attached to the edge of the protrusion 122. This arrangement helps to reduce the flipping distance of the explosion-proof sheet 120, reduces the risk of excessive burst pressure or failure to burst, and helps to reduce the deviation of the burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0051] In one or more embodiments, the cylindrical battery 100 includes a housing 150 and an electrode assembly 160 disposed within the housing 150; the portion of the flip-up portion 121 connected to the protrusion 122 has a second surface 121a facing the electrode assembly 160; the portion of the fixing portion 123 connected to the protrusion 122 has a third surface 123a facing the electrode assembly 160; in the axial direction Y, the distance between the second surface 121a and the third surface 123a does not exceed 0.1 mm, but is not limited thereto. The fixing portion 123 and the flip-up portion 121 do not occupy excessive space within the housing 150, and the flip-up portion 121 of the explosion-proof sheet 120 is closer to the end 113, providing greater space for the electrode assembly 160 within the housing 150 of the cylindrical battery 100, which is beneficial for increasing the volume of the electrode assembly 160 and improving the energy density of the cylindrical battery 100.

[0052] In one or more embodiments, along the axial direction Y, the second surface 121a extends beyond the third surface 123a.

[0053] In one or more embodiments, along the axial direction Y, the third surface 123a extends beyond the second surface 121a.

[0054] In one or more embodiments, the pressing portion 1112 is fitted to the protrusion 122. This arrangement helps to reduce the flipping distance of the explosion-proof sheet 120, reduces the risk of excessive burst pressure or failure to burst, and helps to reduce the deviation in burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0055] In one or more embodiments, the flipping portion 121 includes a groove 121A along the axial direction Y. The projection of the pressing portion 1112 is separate from the projection of the groove 121A. In the radial direction X of the cylindrical battery 100, the groove 121A is closer to the axis L of the cylindrical battery 100 than the pressing portion 1112. This arrangement helps reduce the risk that the explosion-proof sheet 120 will not explode due to the pressing portion 1112 obstructing the groove 121A, and also helps reduce the deviation of the explosion pressure, thereby improving the safety performance of the cylindrical battery 100.

[0056] In one or more embodiments, the groove 121A is a non-closed arc shape. When the internal gas pressure of the cylindrical battery 100 is too high, the groove 121A of the explosion-proof sheet 120 cracks, forming a vent. The high-pressure gas inside the cylindrical battery 100 is released to the outside through the vent. Because the groove 121A is a non-closed arc shape, the flipped portion 121 of the explosion-proof sheet 120 is not easily completely separated, which helps to improve the safety performance of the cylindrical battery 100.

[0057] In one or more embodiments, along the axial direction Y, the projection of the pressing portion 1112 overlaps with the projection of the flipping portion 121. This arrangement helps to reduce the flipping distance of the explosion-proof sheet 120, reduces the risk of excessive burst pressure or failure to burst, and helps to reduce the deviation of the burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0058] In one or more embodiments, the protrusion 122 forms a second space D on the side facing away from the second portion 1111B; the cylindrical battery 100 also includes a perforated plate 130 and an insulating member 140, the perforated plate 130 and the flip portion 121 being electrically connected, and at least a portion of the insulating member 140 being disposed between the perforated plate 130 and the explosion-proof sheet 120 along the axial direction Y, and located in the second space D. This arrangement facilitates providing a receiving space for the insulating member 140, reduces the distance between the portion of the flip portion 121 not electrically connected to the perforated plate 130 and the perforated plate 130, provides a larger receiving space for the electrode assembly 160 within the casing 150 of the cylindrical battery 100, and facilitates increasing the volume of the electrode assembly 160 and improving the energy density of the cylindrical battery 100.

[0059] In one or more embodiments, the housing 150 includes a sidewall 151 surrounding the electrode assembly 160, the sidewall 151 having a protrusion 152 projecting toward the axis L of the cylindrical battery 100, a portion of the top cover 110 being located on the side of the protrusion 152 facing away from the electrode assembly 160; along the axial direction Y, the protrusion 152 includes a first proximal end 152a near the electrode assembly 160, and an end 113 includes a first distal end 113a away from the electrode assembly 160, the distance between the first proximal end 152a and the first distal end 113a being L1 along the axial direction Y; along the axial direction Y, the perforated plate 130 includes a second proximal end 130b near the electrode assembly 160, the distance between the second proximal end 130b and the first distal end 113a being L2 along the axial direction Y; 60% ≤ L2 / L1 ≤ 80%, but not limited thereto. Optionally, 60% ≤ L2 / L1 ≤ 70%. For example, L2 / L1 can be 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, or a range of any two values ​​within this range. Compared to the prior art, L2 / L1 has a smaller proportion. Along the axial direction Y, relative to the first proximal end 152a of the protrusion 152, the perforated plate 130 is closer to the first distal end 113a, which is beneficial for providing a larger accommodating space for the electrode assembly 160 within the casing 150 of the cylindrical battery 100, increasing the volume of the electrode assembly 160, and improving the energy density of the cylindrical battery 100.

[0060] The cylindrical battery 100 of this application is not limited to a primary battery or a secondary battery. In the following embodiments, taking the cylindrical battery 100 as a lithium-ion secondary battery as an example, in one or more embodiments, the electrode assembly 160 includes a first electrode, a second electrode, and a separator. The first electrode and the second electrode have opposite polarities, and the separator is disposed between the first electrode and the second electrode. During the charging and discharging process of the lithium-ion secondary battery, lithium ions are inserted and extracted back and forth between the first electrode and the second electrode.

[0061] In one or more embodiments, the first electrode includes a first body and a first tab, and the second electrode includes a second body and a second tab. The first body includes a first current collector and a first active material layer coated on the surface of the first current collector, and the first tab and the first current collector are connected. The second body includes a second current collector and a second active material layer coated on the surface of the second current collector, and the second tab and the second current collector are connected. The top cover 110 is electrically connected to the first tab of the electrode assembly 160, and the top cover 110 forms the first electrode terminal of the cylindrical battery 100. The housing 150 is electrically connected to the second tab of the electrode assembly 160, forming the second electrode terminal of the cylindrical battery 100. One of the first electrode terminal and the second electrode terminal is a positive electrode, and the other is a negative electrode. Thus, replacing a conventional single electrode terminal simplifies the structure of the cylindrical battery 100. In one or more embodiments, the first tab and the first current collector are integrated. In one or more embodiments, the second tab and the second current collector are integrated.

[0062] In one or more embodiments, both the first tab and the second tab are flattened tabs. Along the axial direction Y, the height of the portion of the protrusion 152 pressing down on the electrode assembly 160 is lower than the height of the center portion of the electrode assembly 160, which helps the protrusion 152 to compact the edge portion of the electrode assembly 160 and improve the positional stability of the electrode assembly 160.

[0063] In one or more embodiments, 3.13mm ≤ L1 ≤ 5.83mm, but is not limited thereto. For example, L1 can be: 3.13mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5.0mm, 5.1mm, 5.2mm, 5.3mm, 5.4mm, 5.5mm, 5.6mm, 5.7mm, 5.8mm, 5.83mm, or a range consisting of any two values ​​within this range. In one or more embodiments, 2.5mm ≤ L2 ≤ 3.5mm, but is not limited thereto. For example, L2 can be: 2.5mm, 2.55mm, 2.6mm, 2.65mm, 2.7mm, 2.75mm, 2.8mm, 2.85mm, 2.9mm, 2.95mm, 3.0mm, 3.05mm, 3.1mm, 3.15mm, 3.2mm, 3.25mm, 3.3mm, 3.35mm, 3.4mm, 3.45mm, 3.5mm, or a range of any two values ​​within this range. Compared to the prior art, along the axial direction Y, the distance between the second proximal end 130b and the first distal end 113a is smaller. The perforated plate 130 is closer to the first distal end 113a than the first proximal end 152a of the protrusion 152. This allows for a larger space to accommodate the electrode assembly 160 within the casing 150 of the cylindrical battery 100, increasing the volume of the electrode assembly 160 and improving the energy density of the cylindrical battery 100.

[0064] Figure 7 is a cross-sectional view of the perforated plate 130 of the cylindrical battery 100 shown in Figure 1. As shown in Figure 7, in one or more embodiments, the perforated plate 130 includes a first surface 130a facing the flip portion 121, and the first surface 130a is flat. This arrangement helps to reduce the distance between the portion of the flip portion 121 not electrically connected to the perforated plate 130 and the perforated plate 130, providing more space for the electrode assembly 160 within the housing 150 of the cylindrical battery 100, thereby increasing the volume of the electrode assembly 160 and improving the energy density of the cylindrical battery 100.

[0065] In one or more embodiments, the flipping portion 121 includes a central region 1211 protruding toward the perforated plate 130, the central region 1211 and the perforated plate 130 being welded together; the central region 1211 extends beyond the second surface 121a by a distance L3 along the direction from the top cover 110 toward the electrode assembly 160, where 0.1 mm ≤ L3 ≤ 0.2 mm, but is not limited thereto. For example, L3 can be 0.10 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, 0.20 mm, or a range consisting of any two values ​​therein. Compared to the prior art, the central region 1211 extends less beyond the second surface 121a in the direction from the top cover 110 to the electrode assembly 160. This helps to reduce the gap between the second surface 121a of the flip portion 121 and the perforated plate 130, providing a larger space for the electrode assembly 160 inside the cylindrical battery 100, increasing the volume of the electrode assembly 160, and improving the energy density of the cylindrical battery 100.

[0066] Figure 8 is a cross-sectional view of the insulating member 140 of the cylindrical battery 100 shown in Figure 1. As shown in Figure 8, in one or more embodiments, the insulating member 140 includes a limiting portion 141, which is disposed on the side of the perforated plate 130 away from the axis L of the cylindrical battery 100. This arrangement helps the insulating member 140 to limit the perforated plate 130 in the radial direction X of the cylindrical battery 100, thereby improving the positional stability of the perforated plate 130.

[0067] Figure 9 is a top view of the top cover 110 of the cylindrical battery 100 shown in Figure 1, Figure 10 is a cross-sectional view of the top cover 110 shown in Figure 9, and Figure 11 is a cross-sectional view of the top cover 110 shown in Figure 10. As shown in Figures 9, 10, and 11, in one or more embodiments, along the circumferential direction R of the cylindrical battery 100, the pressing portion 1112 includes a plurality of spaced pressing segments 11121. Referring to Figure 11, in a circle with the center O of the top cover 110 as the center, the central angle corresponding to the pressing segment 11121 is α, and the sum of the central angles α corresponding to the plurality of pressing segments 11121 is A, where 210°≤A≤270°. The value of A can be 210°, 211°, 212°, 213°, 214°, 215°, 216°, 217°, 218°, 219°, 220°, 221°, 222°, 223°, 224°, 225°, 226°, 227°, 228°, 229°, 230°, 231°, 232°, 233°, 234°, 235°, 236°, 237°, 238°, 239°, 240°, 24 ... 1°, 242°, 243°, 244°, 245°, 246°, 247°, 248°, 249°, 250°, 251°, 252°, 253°, 254°, 255°, 256°, 257°, ​​258°, 259°, 260°, 261°, 262°, 263°, 264°, 265°, 266°, 267°, 268°, 269°, 270°, or a range consisting of any two values ​​within these ranges.

[0068] By adjusting A within the scope of this application, it is beneficial to disperse the stress on the lower pressure part 1112, reduce the impact of the deformation of the lower pressure part 1112 under harsh working conditions on the explosion-proof sheet 120, make the explosion-proof sheet 120 more uniformly stressed, and make the lower pressure part 1112 less prone to deformation. This is beneficial to reduce the flipping distance of the explosion-proof sheet 120, reduce the risk of excessive burst pressure or failure to burst, and reduce the deviation of burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0069] In one or more embodiments, the central angle α of the multiple pressing sections 11121 is equal, which makes the force on the explosion-proof sheet 120 more uniform and the pressing part 1112 less prone to deformation. This helps to reduce the flipping distance of the explosion-proof sheet 120, reduce the risk of excessive burst pressure or failure to burst, and reduce the deviation of burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0070] In one or more embodiments, at least two of the central angles α of the plurality of pressing segments 11121 are not equal.

[0071] In one or more embodiments, the connecting portion 112 includes a plurality of spaced-apart connecting segments 1121 arranged along the axial direction Y. The projections of the pressing segments 11121 and the connecting segments 1121 are staggered around the axis L of the cylindrical battery 100. This arrangement helps to disperse the stress on the pressing portion 1112 and the connecting portion 112, reduces the impact of deformation of the pressing portion 1112 and the connecting portion 112 on each other under harsh working conditions, helps to reduce the flipping distance of the explosion-proof sheet 120, reduces the deviation of the burst pressure, and thus improves the safety performance of the cylindrical battery 100.

[0072] In one or more embodiments, as shown in FIG9, in a circle with the center O of the top cover 110 as the center, the central angle corresponding to the connecting segment 1121 is β. The central angles β of the multiple connecting segments 1121 are all equal, and the multiple connecting segments 1121 are evenly distributed. The top cover 110 is subjected to more uniform force, and the top cover 110 is not easily deformed. This is beneficial to suppress the deformation of the protrusion 122 and the fixing part 123 of the explosion-proof sheet 120, which is beneficial to reduce the flipping distance of the explosion-proof sheet 120, reduce the risk of excessive burst pressure or failure to burst of the explosion-proof sheet 120, and reduce the deviation of burst pressure, thereby improving the safety performance of the cylindrical battery 100.

[0073] Secondly, this application provides a battery pack 200. Figure 12 is a schematic diagram of the structure of the battery pack provided in an embodiment of this application. As shown in Figure 12, the battery pack 200 includes a cylindrical battery 100 from any of the above embodiments. There is at least one cylindrical battery 100. In one or more embodiments, there are multiple cylindrical batteries 100, which may be connected in series or in parallel, or a combination of series and parallel connections.

[0074] Thirdly, this application provides an electrical device 300, including the cylindrical battery 100 or battery pack 200 of any of the above embodiments.

[0075] In one or more embodiments, FIG13 is a schematic diagram of the structure of a first type of electrical device provided in the embodiments of this application. As shown in FIG13, the electrical device 300 includes the battery pack 200 in the above embodiments, and the battery pack 200 includes the cylindrical battery 100 in the above embodiments.

[0076] In one or more embodiments, FIG14 is a schematic diagram of the structure of a second type of electrical device provided in the embodiments of this application. As shown in FIG14, the electrical device 300 includes the cylindrical battery 100 in the above embodiments.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cylindrical battery, characterized by comprising: The cylindrical battery comprises: a top cover comprising a base, a connecting portion and an end portion, the end portion protruding from the base along an axial direction of the cylindrical battery, and the connecting portion connecting the end portion and the base; an explosion-proof sheet, at least a portion of the explosion-proof sheet and the top cover being arranged along the axial direction; the base comprises an extension portion and a pressing portion, the pressing portion being arranged on a side of the extension portion facing the axial direction of the cylindrical battery, the pressing portion protruding from the extension portion towards the explosion-proof sheet, and the pressing portion abutting the explosion-proof sheet.

2. The cylindrical battery according to claim 1, characterized by, The extension portion comprises a first portion and a second portion, a projection of the first portion surrounding a projection of the second portion along the axial direction, and the pressing portion protruding from the second portion towards the explosion-proof sheet; the second portion protrudes away from the explosion-proof sheet relative to the first portion, and a first space is formed on a side of the second portion facing the explosion-proof sheet, and a portion of the explosion-proof sheet is located in the first space.

3. The cylindrical battery according to claim 2, characterized by The explosion-proof sheet comprises a turning portion, a protruding portion and a fixing portion arranged along a radial direction of the cylindrical battery, the fixing portion being connected to the first portion, and at least a portion of the protruding portion being located in the first space.

4. The cylindrical battery according to claim 3, characterized by The pressing portion abuts the protruding portion.

5. The cylindrical battery according to claim 4, characterized by The turning portion comprises a notch, a projection of the pressing portion being separated from a projection of the notch along the axial direction, and the notch being closer to the axial direction of the cylindrical battery than the pressing portion along a radial direction of the cylindrical battery.

6. The cylindrical battery according to claim 5, characterized by A projection of the pressing portion partially overlaps a projection of the turning portion along the axial direction.

7. The cylindrical battery according to any one of claims 3 to 6, characterized by, A second space is formed on a side of the protruding portion away from the second portion; The cylindrical battery further comprises a hole plate and an insulating member, the hole plate being electrically connected to the turning portion, and at least a portion of the insulating member being arranged between the hole plate and the explosion-proof sheet along the axial direction and located in the second space.

8. The cylindrical battery according to claim 7, characterized by The insulating member comprises a limiting portion arranged on a side of the hole plate away from the axial direction of the cylindrical battery.

9. The cylindrical battery according to claim 7 or 8, characterized by The hole plate comprises a first surface facing the turning portion, and the first surface is arranged flat.

10. The cylindrical battery according to any one of claims 1 to 9, characterized by, The pressing portion comprises a plurality of pressing segments arranged at intervals along a circumferential direction of the cylindrical battery, and a sum of corresponding central angles α of the plurality of pressing segments is A, 210°≤A≤270°.

11. The cylindrical battery according to claim 10, characterized by The connecting portion comprises a plurality of connecting segments arranged at intervals, and projections of the pressing segments and projections of the connecting segments are arranged alternately around the axial direction along the axial direction.

12. A battery pack, characterized by, The cylindrical battery of any one of claims 1 to 11.

13. An electrical device, characterized by The battery pack of claim 12 or the cylindrical battery of any one of claims 1 to 11.

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