Cylindrical battery monomer, battery device and power utilization device

Abstract

The utility model provides a cylindrical battery monomer, a battery device and a power utilization device. The cylindrical battery cell includes a housing having a first wall portion provided with a terminal hole, an electrode assembly, and an electrode terminal. The electrode assembly is housed within the housing. The electrode terminal is electrically connected with the electrode assembly and comprises a main body part and a first limiting part, the main body part penetrates through the terminal hole, and the first limiting part is connected to the main body part. In the thickness direction of the first wall part, the first limiting part is located on the side, facing the electrode assembly, of the first wall part, and the first limiting part is configured to limit the electrode terminal to be separated from the terminal hole in the direction away from the electrode assembly. The hardness of the first limiting part ranges from 25 HV to 70 HV. When the hardness of the first limiting part is 25HV-70HV, the risk that the electrode terminal is separated from the first wall part under the action of the internal air pressure of the cylindrical battery monomer can be reduced, and the reliability of the cylindrical battery monomer is improved.

Description

Technical Field

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

[0002] Batteries are widely used in new energy applications, such as electric vehicles and new energy vehicles. These have become a new trend in the automotive industry. The development of battery technology requires consideration of multiple design factors, including performance parameters such as battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must be considered. However, current battery reliability is relatively poor. Utility Model Content

[0003] The purpose of the embodiments of the present application is to provide a cylindrical battery cell, a battery device, and an electrical device, which are intended to improve the problem of poor reliability of batteries in the related art.

[0004] In the first aspect, an embodiment of the present application provides a cylindrical battery cell, which includes a shell, an electrode assembly and an electrode terminal, the shell having a first wall portion, the first wall portion being provided with a terminal hole; the electrode assembly is accommodated in the shell; the electrode terminal is electrically connected to the electrode assembly, the electrode terminal includes a main body portion and a first limiting portion, the main body portion is passed through the terminal hole, the first limiting portion is connected to the main body portion, and along the thickness direction of the first wall portion, the first limiting portion is located on the side of the first wall portion facing the electrode assembly, and the first limiting portion is configured to limit the electrode terminal from detaching from the terminal hole in a direction away from the electrode assembly; wherein the hardness of the first limiting portion is 25HV~70HV.

[0005] In the above technical solution, the first stopper prevents the electrode terminal from disengaging from the terminal hole in a direction away from the electrode assembly, reducing the risk of the electrode terminal disengaging from the first wall under the influence of the internal air pressure of the cylindrical battery cell. When the hardness of the first stopper is greater than or equal to 25 HV, the first stopper has a relatively high hardness and a correspondingly high yield strength, making it less likely to deform under the influence of the internal air pressure of the cylindrical battery cell. This reduces the risk of the electrode terminal disengaging from the first wall under the influence of the internal air pressure of the cylindrical battery cell and improves the reliability of the cylindrical battery cell. When the hardness of the first stopper is less than or equal to 70 HV, the hardness of the first stopper is not excessive, thereby facilitating the production of the electrode terminal and reducing the manufacturing cost of the cylindrical battery cell. Therefore, when the hardness of the first stopper is between 25 HV and 70 HV, the risk of the electrode terminal disengaging from the first wall under the influence of the internal air pressure of the cylindrical battery cell is reduced, improving the reliability of the cylindrical battery cell, and facilitating the production of the electrode terminal and reducing the manufacturing cost of the cylindrical battery cell.

[0006] As an optional technical solution of an embodiment of the present application, the hardness of the first limiting portion is 35HV to 50HV.

[0007] In the above technical solution, when the hardness of the first limiting portion is greater than or equal to 35 HV, the first limiting portion has a greater hardness and a correspondingly higher yield strength, making the first limiting portion less likely to deform under the internal air pressure of the cylindrical battery cell. This further reduces the risk of the electrode terminal detaching from the first wall portion under the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When the hardness of the first limiting portion is less than or equal to 50 HV, the hardness of the first limiting portion is not excessive, thereby facilitating the production of the electrode terminal and reducing the manufacturing cost of the cylindrical battery cell. Therefore, when the hardness of the first limiting portion is between 35 HV and 50 HV, the risk of the electrode terminal detaching from the first wall portion under the internal air pressure of the cylindrical battery cell is further reduced, thereby improving the reliability of the cylindrical battery cell, facilitating the production of the electrode terminal, and reducing the manufacturing cost of the cylindrical battery cell.

[0008] As an optional technical solution of the embodiment of the present application, along the thickness direction of the first wall portion, the minimum thickness of the first limiting portion is H1, which satisfies: 1mm≤H1≤2.5mm.

[0009] In the above technical solution, when H1 ≥ 1mm, the minimum thickness of the first limiting portion is relatively thick, the yield strength of the first limiting portion is relatively high, and the risk of the first limiting portion deforming under the internal air pressure of the cylindrical battery cell is reduced. This reduces the risk of the electrode terminal detaching from the first wall portion under the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When H1 ≤ 2.5mm, the minimum thickness of the first limiting portion is not excessively large, and the thickness of the first limiting portion is not excessively thick. This not only helps reduce material consumption for the electrode terminal and the cost of the cylindrical battery cell, but also helps reduce the internal space occupied by the cylindrical battery cell, reduce the weight of the cylindrical battery cell, and improve the energy density of the cylindrical battery cell. Therefore, when 1mm ≤ H1 ≤ 2.5mm, both the reliability and energy density of the cylindrical battery cell can be taken into account.

[0010] As an optional technical solution of the embodiment of the present application, 1mm≤H1≤1.5mm.

[0011] In the above technical solution, when H1 ≥ 1mm, the minimum thickness of the first limiting portion is thicker, the yield strength of the first limiting portion is greater, and the risk of the first limiting portion deforming under the internal air pressure of the cylindrical battery cell is reduced. This reduces the risk of the electrode terminal detaching from the first wall portion under the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When H1 ≤ 1.5mm, the minimum thickness of the first limiting portion is not too large, and the thickness of the first limiting portion is not too thick. This not only helps reduce material consumption of the electrode terminal and lower the cost of the cylindrical battery cell, but also helps reduce the internal space occupied by the cylindrical battery cell, reduce the weight of the cylindrical battery cell, and improve the energy density of the cylindrical battery cell. Therefore, when 1mm ≤ H1 ≤ 1.5mm, it is possible to better balance the reliability and energy density of the cylindrical battery cell.

[0012] As an optional technical solution of the embodiment of the present application, the first limiting portion is disc-shaped, the diameter of the outer edge of the first limiting portion is D1, and the diameter of the terminal hole is D2, satisfying: 1.5≤D1 / D2≤2.2.

[0013] In the above technical solution, when D1 / D2 ≥ 1.5, the ratio of the outer edge diameter of the first retaining portion to the diameter of the terminal hole is large. This allows the first retaining portion to protrude significantly beyond the terminal hole, i.e., the area of ​​the first retaining portion relative to the first wall portion is larger. This improves the retaining effect of the first retaining portion, further reducing the risk of the electrode terminal detaching from the first wall portion under the influence of internal air pressure within the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When D1 / D2 ≤ 2.2, the ratio of the outer edge diameter of the first retaining portion to the diameter of the terminal hole is not excessive, and the portion of the first retaining portion protruding beyond the terminal hole is not excessive. This further reduces the distance between the first retaining portion and other walls of the housing, thus reducing the risk of the first retaining portion contacting other walls and causing a short circuit when the housing deforms. Furthermore, when the first retaining portion deforms under external force, it is less likely to be inserted into the electrode assembly, preventing the positive and negative electrode tabs from overlapping and causing a short circuit, thereby improving the reliability of the cylindrical battery cell. Therefore, when 1.5≤D1 / D2≤2.2, the cylindrical battery cell has higher reliability.

[0014] As an optional technical solution of an embodiment of the present application, 1.8≤D1 / D2≤2.

[0015] In the above technical solution, when D1 / D2 ≥ 1.8, the ratio of the diameter of the outer edge of the first retaining portion to the diameter of the terminal hole is greater. This increases the portion of the first retaining portion that protrudes beyond the terminal hole, meaning that the area of ​​the first retaining portion relative to the first wall portion is larger. This provides a better retaining effect, further reducing the risk of the electrode terminal detaching from the first wall portion under the influence of internal air pressure within the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When D1 / D2 ≤ 2, the ratio of the diameter of the outer edge of the first retaining portion to the diameter of the terminal hole is not excessive, and the portion of the first retaining portion that protrudes beyond the terminal hole is not excessive. This further reduces the distance between the first retaining portion and other walls of the housing, further reducing the risk of the first retaining portion contacting other walls of the housing and causing a short circuit when the housing deforms. Furthermore, when the first retaining portion deforms under external force, it is less likely to be inserted into the electrode assembly, reducing the risk of overlapping positive and negative electrode tabs and causing a short circuit, thereby improving the reliability of the cylindrical battery cell. Therefore, when 1.5≤D1 / D2≤2.2, the cylindrical battery cell has higher reliability.

[0016] As an optional technical solution of the embodiment of the present application, 24mm≤D1≤36mm.

[0017] In the above technical solution, when D1 ≥ 24 mm, the outer edge diameter of the first retaining portion is larger, which helps to increase the portion of the first retaining portion that protrudes beyond the terminal hole. That is, the area of ​​the first retaining portion relative to the first wall is larger, resulting in a better retaining effect of the first retaining portion. This helps reduce the risk of the electrode terminal detaching from the first wall due to the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When D1 ≤ 36 mm, the outer edge diameter of the first retaining portion is not too large. On the one hand, the first retaining portion is farther away from other walls of the outer shell, which helps reduce the risk of the first retaining portion contacting other walls of the outer shell and causing a short circuit when the outer shell deforms. On the other hand, when the first retaining portion is deformed by external forces, it is difficult for the first retaining portion to be inserted into the electrode assembly, preventing the positive and negative electrode tabs from overlapping and causing a short circuit, thereby improving the reliability of the cylindrical battery cell. Therefore, when 24 mm ≤ D1 ≤ 36 mm, the cylindrical battery cell has high reliability.

[0018] As an optional technical solution of the embodiment of the present application, 28mm≤D1≤34mm.

[0019] In the above technical solution, when D1 ≥ 28 mm, the outer edge diameter of the first retaining portion is larger, which helps increase the portion of the first retaining portion that extends beyond the terminal hole. That is, the area of ​​the first retaining portion relative to the first wall is larger, resulting in a better retaining effect for the first retaining portion. This helps reduce the risk of the electrode terminal detaching from the first wall due to the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell. When D1 ≤ 34 mm, on the one hand, the first retaining portion is further away from the other walls of the housing, which helps reduce the risk of the first retaining portion contacting other walls of the housing and causing a short circuit when the housing deforms. On the other hand, when the first retaining portion deforms under external force, it is less likely to be inserted into the electrode assembly, making it less likely that the positive and negative electrode tabs will overlap and short-circuit, thereby improving the reliability of the cylindrical battery cell. Therefore, when 24 mm ≤ D1 ≤ 36 mm, the cylindrical battery cell has higher reliability.

[0020] As an optional technical solution of the embodiment of the present application, the diameter of the terminal hole is D2, and the diameter of the outer surface of the shell is D3, satisfying: 0.28≤D2 / D3≤0.4.

[0021] In the technical solution, when D2 / D3≤0.4, the diameter of the terminal hole is smaller than the diameter of the outer surface of the shell, and the terminal hole occupies a smaller area of the first wall part. On the one hand, the remaining part of the first wall part has a larger area, the first wall part has a larger strength, and the first wall part is less likely to deform, which is conducive to reducing the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell. On the other hand, the electrode terminal is relatively small when the terminal hole is small, which is conducive to reducing the action area of the internal gas and the electrode terminal, thereby reducing the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell. When D2 / D3≥0.28, the diameter of the terminal hole is not too small relative to the diameter of the outer surface of the shell, so that the electrode terminal is not too small. On the one hand, the electrode terminal can be conveniently installed, and on the other hand, the overcurrent capacity of the electrode terminal is relatively strong. Therefore, when 0.28≤D2 / D3≤0.4, both the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell and the installation of the electrode terminal are facilitated, and the overcurrent capacity of the electrode terminal is relatively strong.

[0022] As an optional technical solution of the embodiment of the application, 0.32≤D2 / D3≤0.36.

[0023] In the technical solution, when D2 / D3≤0.4, the diameter of the terminal hole is smaller than the diameter of the outer surface of the shell, and the terminal hole occupies a smaller area of the first wall part. On the one hand, the remaining part of the first wall part has a larger area, the first wall part has a larger strength, and the first wall part is less likely to deform, which is conducive to reducing the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell. On the other hand, the electrode terminal is relatively small when the terminal hole is small, which is conducive to reducing the action area of the internal gas and the electrode terminal, thereby reducing the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell. When D2 / D3≥0.28, the diameter of the terminal hole is not too small relative to the diameter of the outer surface of the shell, so that the electrode terminal is not too small. On the one hand, the electrode terminal can be conveniently installed, and on the other hand, the overcurrent capacity of the electrode terminal is relatively strong. Therefore, when 0.28≤D2 / D3≤0.4, both the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell and the installation of the electrode terminal are facilitated, and the overcurrent capacity of the electrode terminal is relatively strong. Therefore, when 0.28≤D2 / D3≤0.4, both the risk that the electrode terminal is separated from the first wall part under the action of the internal gas pressure of the cylindrical battery cell and the installation of the electrode terminal are facilitated, and the overcurrent capacity of the electrode terminal is relatively strong.

[0024] As an optional technical solution of the embodiment of the application, 38mm≤D3≤80mm.

[0025] As an optional technical solution of the embodiment of the application, 14mm≤D2≤21mm.

[0026] In the above technical solution, when D2 ≤ 21 mm, the diameter of the terminal hole is relatively small, and the electrode terminal is also relatively small, which helps to reduce the area of ​​interaction between the internal gas and the electrode terminal, thereby reducing the risk of the electrode terminal detaching from the first wall under the influence of the internal air pressure of the cylindrical battery cell. When D2 ≥ 14 mm, the diameter of the terminal hole is not too small, so that the electrode terminal is not too small. On the one hand, it can facilitate the installation of the electrode terminal, and on the other hand, it is conducive to making the electrode terminal have a stronger flow capacity. Therefore, when 14 mm ≤ D2 ≤ 21 mm, it is conducive to reducing the risk of the electrode terminal detaching from the first wall under the influence of the internal air pressure of the cylindrical battery cell, and it is convenient to install the electrode terminal, so that the electrode terminal has a stronger flow capacity.

[0027] As an optional technical solution of an embodiment of the present application, the material of the first wall portion includes steel, and the thickness of the first wall portion is H2, satisfying: 0.4mm≤H2≤1mm.

[0028] In the above technical solution, steel has a high strength and can effectively improve the structural strength of the first wall, which helps reduce the risk of deformation of the first wall due to stress, and reduces the risk of the electrode terminal detaching from the first wall due to the internal air pressure of the cylindrical battery cell, which helps improve the reliability of the cylindrical battery cell. When H2 ≥ 0.4mm, the thickness of the first wall is relatively large, and the first wall has a high structural strength, which helps reduce the risk of deformation of the first wall due to stress, and reduces the risk of the electrode terminal detaching from the first wall due to the internal air pressure of the cylindrical battery cell, which helps improve the reliability of the cylindrical battery cell. When H2 ≤ 1mm, the thickness of the first wall is not too large, which helps reduce the material consumption of the first wall and reduces the cost of the cylindrical battery cell. Therefore, when 0.4mm ≤ H2 ≤ 1mm, the reliability and cost of the cylindrical battery cell can be taken into account.

[0029] As an optional technical solution of the embodiment of the present application, 0.6mm≤H2≤0.8mm.

[0030] In the above technical solution, when H2 ≥ 0.6mm, the thickness of the first wall is greater, the first wall has higher structural strength, and is more conducive to reducing the risk of deformation of the first wall due to stress, and reducing the risk of the electrode terminal detaching from the first wall due to the internal air pressure of the cylindrical battery cell, which is conducive to improving the reliability of the cylindrical battery cell. When H2 ≤ 0.8mm, the thickness of the first wall is not too large, which is more conducive to reducing the material consumption of the first wall and reducing the cost of the cylindrical battery cell. Therefore, when 0.6mm ≤ H2 ≤ 0.8mm, the reliability and cost of the cylindrical battery cell can be balanced.

[0031] As an optional technical solution of the embodiment of the application, the main body part has an outer peripheral surface, the first limiting part has a first surface facing the first wall part, and the outer peripheral surface and the first surface are connected by a chamfer surface.

[0032] In the above technical solution, by connecting the outer peripheral surface and the first surface by the chamfer surface, on the one hand, the outer peripheral surface and the first surface can be smoothly transitioned, stress concentration is reduced, and the risk of deformation of the first limiting part at this position is reduced. On the other hand, the chamfer can play the role of a reinforcing rib to a certain extent, further reducing the risk of deformation of the first limiting part.

[0033] As an optional technical solution of the embodiment of the application, the chamfer surface has a circular arc cross section.

[0034] In the above technical solution, the chamfer surface has a circular arc cross section, so the chamfer is a round corner, which can effectively reduce stress concentration.

[0035] As an optional technical solution of the embodiment of the application, the chamfer surface has a straight line cross section.

[0036] In the above technical solution, the chamfer surface has a straight line cross section, so the chamfer is an oblique corner, which can effectively reduce stress concentration.

[0037] As an optional technical solution of the embodiment of the application, along the radial direction of the cylindrical battery monomer, the distance from the connecting position of the chamfer surface and the first surface to the outer peripheral surface is L, which satisfies: 0.1mm≤L≤0.6mm.

[0038] In the above technical solution, when L≥0.1mm, the distance from the connecting position of the chamfer surface and the first surface to the outer peripheral surface along the radial direction of the cylindrical battery monomer is large, the effect of reducing stress concentration is good, and it has good reinforcing effect. When L≤0.6mm, the distance from the connecting position of the chamfer surface and the first surface to the outer peripheral surface along the radial direction of the cylindrical battery monomer is not too large, which can reduce the risk of interference with other components. Therefore, when 0.1mm≤L≤0.6mm, stress concentration can be effectively reduced, and interference with other components is not easy.

[0039] As an optional technical solution of the embodiment of the application, 0.3mm≤L≤0.5mm.

[0040] In the above technical solution, when L is greater than or equal to 0.3 mm, the distance from the connecting position of the chamfer surface and the first surface to the outer peripheral surface along the radial direction of the cylindrical battery monomer is greater, the effect of reducing stress concentration is better, and the reinforcing effect is better. When L is less than or equal to 0.5 mm, the distance from the connecting position of the chamfer surface and the first surface to the outer peripheral surface along the radial direction of the cylindrical battery monomer is not too large, and the risk of interference with other components can be reduced. Therefore, when 0.3 mm≤L≤0.5 mm, the stress concentration can be effectively reduced, and the interference with other components is less likely to occur.

[0041] As an optional technical solution of the embodiment of the present application, in the cross section of the cylindrical battery monomer, the included angle between the chamfer surface and the first surface is C, which satisfies 125°≤C≤145°, and the cross section is parallel to the axial direction of the cylindrical battery monomer.

[0042] In the above technical solution, when 125°≤C≤145°, the size of the chamfer is moderate, which is conducive to reducing stress concentration and reinforcing to a certain extent.

[0043] As an optional technical solution of the embodiment of the present application, the electrode terminal comprises a second limiting portion connected to one end of the main body portion away from the inside of the shell, and the second limiting portion cooperates with the first limiting portion to clamp the first wall portion.

[0044] In the above technical solution, by arranging the first limiting portion and the second limiting portion at two ends of the main body portion respectively, the first limiting portion and the second limiting portion can cooperate to clamp the first wall portion, so as to limit the main body portion in the terminal hole. The first limiting portion can limit the main body portion from escaping from the terminal hole in a direction away from the electrode assembly, and the second limiting portion can limit the main body portion from escaping from the terminal hole in a direction facing the electrode assembly. The first limiting portion and the second limiting portion jointly act on the main body portion, and have a good limiting effect on the main body portion.

[0045] As an optional technical solution of the embodiment of the present application, the diameter of the outer edge of the second limiting portion is less than the diameter of the outer edge of the first limiting portion.

[0046] In the above technical solution, when the diameter of the outer edge of the second limiting portion is less than the diameter of the outer edge of the first limiting portion, the second limiting portion can be riveted to the first wall portion from the side of the first wall portion away from the inside of the shell.

[0047] As an optional technical solution of the embodiment of the present application, the diameter of the outer edge of the second limiting portion is greater than the diameter of the outer edge of the first limiting portion.

[0048] In the above technical solution, when the diameter of the outer edge of the second limiting portion is greater than the diameter of the outer edge of the first limiting portion, the first limiting portion may be riveted to the first wall portion from the side of the first wall portion facing the interior of the shell.

[0049] As an optional technical solution of the embodiment of the present application, the second limiting portion is a riveted portion formed by riveting.

[0050] In the above technical solution, when the second limiting portion is a riveted portion formed by riveting, the second limiting portion may be riveted to the first wall portion from a side of the first wall portion facing away from the interior of the housing.

[0051] As an optional technical solution of an embodiment of the present application, the first limiting portion is a riveted portion formed by riveting.

[0052] In the above technical solution, when the first limiting portion is a riveted portion formed by riveting, the first limiting portion may be riveted to the first wall portion from a side of the first wall portion facing the interior of the shell.

[0053] As an optional technical solution of an embodiment of the present application, the outer shell includes a shell and an end cover, the shell includes a bottom wall and a side wall, the side wall is arranged around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall is enclosed to form an opening; the end cover closes the opening; wherein, the bottom wall is the first wall portion.

[0054] In the above technical solution, the bottom wall is the first wall portion, and the electrode terminal is arranged on the bottom wall. In this way, it is more convenient to install the electrode terminal, which is conducive to accurate installation of the electrode terminal and makes the connection between the electrode terminal and the electrode assembly more stable.

[0055] In a second aspect, an embodiment of the present application further provides a battery device, which includes the above-mentioned cylindrical battery cell.

[0056] In a third aspect, an embodiment of the present application further provides an electric device, which includes the above-mentioned cylindrical battery cell, and the cylindrical battery cell is used to provide electric energy for the electric device. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0058] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0059] Figure 2 An exploded view of a battery device provided in some embodiments of the present application;

[0060] Figure 3 A schematic structural diagram of a cylindrical battery cell provided in some embodiments of the present application;

[0061] Figure 4 An exploded view of a cylindrical battery cell provided in some embodiments of the present application;

[0062] Figure 5 A top view of a cylindrical battery cell provided in some embodiments of the present application;

[0063] Figure 6 for Figure 5 Cross-sectional view at the AA position;

[0064] Figure 7 A schematic diagram of the structure of electrode terminals provided in some embodiments of the present application;

[0065] Figure 8 A cross-sectional view of an electrode terminal provided in some embodiments of the present application;

[0066] Figure 9 Cross-sectional views of electrode terminals provided in some other embodiments of the present application.

[0067] Icons: 10-box; 11-first box body; 12-second box body; 20-cylindrical battery cell; 21-shell; 211-shell; 2111-side wall; 2112-bottom wall; 212-end cover; 213-first wall; 2131-terminal hole; 22-electrode assembly; 221-main body; 222-ear; 23-electrode terminal; 231-first limiting portion; 2311-first surface; 232-main body; 2321-outer peripheral surface; 233-second limiting portion; 234-chamfered surface; 100-battery device; 200-controller; 300-motor; 1000-vehicle. DETAILED DESCRIPTION

[0068] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0069] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only 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 drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0070] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the 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.

[0071] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0072] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0073] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0074] The term "plurality" used in this application refers to two or more (including two).

[0075] In the embodiment of the present application, the cylindrical battery cell may be a secondary battery. A secondary battery refers to a cylindrical battery cell that can be recharged to activate the active material after discharge and continue to be used.

[0076] Cylindrical battery cells include but are not limited to lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0077] Cylindrical battery cells typically include an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a cylindrical battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. A separator, placed between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0078] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0079] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0080] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0081] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include but are not limited to lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) and at least one of its modified compounds, etc.

[0082] In some embodiments, a positive electrode may utilize a metal foam. The metal foam may include nickel foam, copper foam, aluminum foam, alloy foam, or the like. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not include a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled or / and deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0083] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0084] As an example, the negative electrode current collector may be a metal foil, a metal foam, or a composite current collector. For example, the metal foil may be silver-surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium. The metal foam may be nickel foam, copper foam, aluminum foam, or alloy foam. The composite current collector may include a polymer base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy, etc.) on a polymer substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0085] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0086] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0087] As an example, the negative electrode active material may adopt the negative electrode active material for cylindrical battery cells that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites and silicon alloys. The tin-based material can be selected from at least one of elemental tin, tin oxide compounds and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0088] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0089] In some embodiments, the separator is a separator membrane, which can be any known porous separator membrane with good chemical and mechanical stability.

[0090] As an example, the separator can be made of at least one of fiberglass, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film. In the case of a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0091] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0092] In some embodiments, the cylindrical battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0093] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium bisoxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0094] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0095] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0096] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0097] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, or the like.

[0098] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0099] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0100] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0101] In some embodiments, the electrode assembly is a laminate structure.

[0102] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0103] As an example, multiple positive electrode sheets may be provided, and the negative electrode sheet is folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0104] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0105] As an example, multiple separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0106] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0107] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0108] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive electrode tab and a negative electrode tab.

[0109] In some embodiments, a cylindrical battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0110] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple cylindrical battery cells connected in series, parallel, or hybrid via a busbar.

[0111] In some embodiments, a battery cell assembly is typically formed by arranging a plurality of cylindrical battery cells. As an example, the battery cell assembly may be a battery module, which is formed by arranging and fixing a plurality of cylindrical battery cells to form an independent module.

[0112] As an example, a battery module may be formed by bundling a plurality of cylindrical battery cells by cable ties.

[0113] In some embodiments, the battery device may be a battery pack, which may include a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0114] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0115] As an example, the battery cell assembly may also be housed in the box by directly fixing a plurality of cylindrical battery cells to the box.

[0116] As an example, the housing may include a first housing body and a second housing body. The first and second housing bodies engage to form an enclosed space within the housing to house the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first housing body may be a top cover or a bottom plate.

[0117] As an example, the box body may include a top cover, a frame, and a bottom plate, wherein the top cover and the bottom plate are respectively connected to the frame, so that a closed space is formed inside the box body to accommodate the battery cell assembly.

[0118] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0119] In some embodiments, the battery device refers to an energy storage device, which includes a box with a door on at least one side. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0120] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0121] The development of battery technology requires simultaneous consideration of multiple design factors, including performance parameters such as battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must be considered. However, current battery reliability is relatively poor.

[0122] In some embodiments, to improve the reliability of cylindrical battery cells, a pressure relief mechanism may be provided on the outer shell of the cylindrical battery cell. When the cylindrical battery cell experiences thermal runaway, the pressure inside the cylindrical battery cell may be released through the pressure relief mechanism.

[0123] A pressure relief mechanism is a component or part that activates to release internal pressure when the internal pressure of a cylindrical battery cell reaches a predetermined threshold. This threshold varies depending on the design requirements. It may depend on the materials of one or more of the positive and negative electrode plates, electrolyte, and separator in the cylindrical battery cell.

[0124] The "activation" mentioned in this application refers to the action of the pressure relief mechanism or its activation to a certain state, thereby allowing the internal pressure of the cylindrical battery cell to be released. The action produced by the pressure relief mechanism may include, but is not limited to: at least a part of the pressure relief mechanism is ruptured, broken, torn or opened, etc. When the pressure relief mechanism is actuated, the high-temperature and high-pressure substances inside the cylindrical battery cell will be discharged outward from the actuated part as emissions. In this way, the cylindrical battery cell can be depressurized under controllable pressure, thereby avoiding potential more serious accidents.

[0125] The emissions from the cylindrical battery cells mentioned in the embodiments of the present application include but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of the isolation membrane, high-temperature and high-pressure gas generated by the reaction, flames, etc.

[0126] Cylindrical battery cells include electrode terminals, which are located in the outer casing and electrically connected to the electrode assembly, allowing electrical energy to be transferred to or from the cylindrical battery cell through the electrode terminals. However, research has found that before the internal pressure of the cylindrical battery cell reaches a predetermined threshold (before the pressure relief mechanism is activated), the electrode terminals may detach from the outer casing due to the internal pressure, resulting in poor battery reliability.

[0127] In order to solve the problem of poor reliability of cylindrical battery cells, an embodiment of the present application provides a cylindrical battery cell, which includes a shell, an electrode assembly and an electrode terminal. The shell has a first wall portion, and the first wall portion is provided with a terminal hole. The electrode assembly is accommodated in the shell. The electrode terminal is electrically connected to the electrode assembly. The electrode terminal includes a main body portion and a first limiting portion. The main body portion is passed through the terminal hole, and the first limiting portion is connected to the main body portion. Along the thickness direction of the first wall portion, the first limiting portion is located on the side of the first wall portion facing the electrode assembly, and the first limiting portion is configured to limit the electrode terminal from detaching from the terminal hole in a direction away from the electrode assembly. Wherein, the hardness of the first limiting portion is 25HV to 70HV.

[0128] The first stopper prevents the electrode terminal from dislodging from the terminal hole in a direction away from the electrode assembly, reducing the risk of the electrode terminal dislodging from the first wall under the influence of the internal air pressure of the cylindrical battery cell. When the hardness of the first stopper is greater than or equal to 25 HV, the first stopper has a relatively high hardness and a correspondingly high yield strength, making it less likely to deform under the influence of the internal air pressure of the cylindrical battery cell. This reduces the risk of the electrode terminal dislodging from the first wall under the influence of the internal air pressure of the cylindrical battery cell and improves the reliability of the cylindrical battery cell. When the hardness of the first stopper is less than or equal to 70 HV, the hardness of the first stopper is not excessive, thereby facilitating the production of the electrode terminal and reducing the manufacturing cost of the cylindrical battery cell. Therefore, when the hardness of the first stopper is between 25 HV and 70 HV, the risk of the electrode terminal dislodging from the first wall under the influence of the internal air pressure of the cylindrical battery cell is reduced, improving the reliability of the cylindrical battery cell, and facilitating the production of the electrode terminal and reducing the manufacturing cost of the cylindrical battery cell.

[0129] The cylindrical battery cells described in the embodiments of the present application are suitable for battery devices and electrical devices using the cylindrical battery cells.

[0130] Electrical devices can include vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. Vehicles can be fuel-powered, gas-powered, or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid vehicles, or extended-range vehicles. Spacecraft include aircraft, rockets, space shuttles, and spacecraft. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. 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.

[0131] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0132] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of the present application. A battery device 100 is disposed within vehicle 1000. Battery device 100 can be located at the bottom, front, or rear of vehicle 1000. Battery device 100 can be used to power vehicle 1000. For example, battery device 100 can serve as the operating power source of vehicle 1000.

[0133] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery device 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0134] In some embodiments of the present application, the battery device 100 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0135] Please refer to Figure 2 , Figure 2 The exploded view of the battery device 100 provided in some embodiments of the present application. The battery device 100 may include a housing 10 and cylindrical battery cells 20 , wherein the housing 10 is used to accommodate the cylindrical battery cells 20 .

[0136] Among them, a closed space for accommodating the cylindrical battery cells 20 is formed inside the box body 10. The box body 10 can adopt a variety of structures. In some embodiments, the box body 10 may include a first box body 11 and a second box body 12, and the first box body 11 and the second box body 12 are buckled with each other. The first box body 11 and the second box body 12 can be in various shapes, such as a rectangular parallelepiped, a cylinder, etc. The first box body 11 can be a hollow structure with one side open, and the second box body 12 can also be a hollow structure with one side open. The open side of the second box body 12 is buckled with the open side of the first box body 11 to form a box body 10 with a closed space. The first box body 11 can also be a hollow structure with one side open, and the second box body 12 is a plate-like structure. The second box body 12 is buckled with the open side of the first box body 11 to form a box body 10 with an accommodating space.

[0137] In the battery device 100, there can be one or more cylindrical battery cells 20. If there are multiple cylindrical battery cells 20, the multiple cylindrical battery cells 20 can be connected in series, parallel, or in a hybrid connection. Hybrid connection refers to the multiple cylindrical battery cells 20 being connected both in series and in parallel. Multiple cylindrical battery cells 20 can be connected in series, parallel, or in a hybrid connection to form a battery module, which is then connected in series, parallel, or in a hybrid connection to form a whole and housed within the housing 10. Alternatively, all cylindrical battery cells 20 can be directly connected in series, parallel, or in a hybrid connection, and then the whole formed by all cylindrical battery cells 20 is housed within the housing 10.

[0138] In some embodiments, the battery device 100 may further include a busbar component, through which the plurality of cylindrical battery cells 20 can be electrically connected to each other, thereby enabling series connection, parallel connection, or hybrid connection of the plurality of cylindrical battery cells 20. The busbar component may be a metal conductor, such as copper, iron, aluminum, stainless steel, or an aluminum alloy.

[0139] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 , Figure 3 This is a schematic structural diagram of a cylindrical battery cell 20 provided in some embodiments of the present application. Figure 4 An exploded view of a cylindrical battery cell 20 provided in some embodiments of the present application. Figure 5 A top view of a cylindrical battery cell 20 provided in some embodiments of the present application. Figure 6 for Figure 5 Cross-sectional view at the AA position. An embodiment of the present application provides a cylindrical battery cell 20, which includes a shell 21, an electrode assembly 22 and an electrode terminal 23. The shell 21 has a first wall portion 213, and the first wall portion 213 is provided with a terminal hole 2131. The electrode assembly 22 is accommodated in the shell 21. The electrode terminal 23 is electrically connected to the electrode assembly 22. The electrode terminal 23 includes a main body 232 and a first limiting portion 231. The main body 232 is passed through the terminal hole 2131, and the first limiting portion 231 is connected to the main body 232. Along the thickness direction of the first wall portion 213, the first limiting portion 231 is located on the side of the first wall portion 213 facing the electrode assembly 22. The first limiting portion 231 is configured to limit the electrode terminal 23 from disengaging from the terminal hole 2131 in a direction away from the electrode assembly 22. The hardness of the first limiting portion 231 is 25HV to 70HV.

[0140] The cylindrical battery cell 20 refers to the smallest unit constituting the battery device 100 .

[0141] The housing 21 includes a shell 211 and an end cap 212. The shell 211 has a receiving space with one end open, and the receiving space is used to receive the electrode assembly 22. The end cap 212 is connected to the shell 211 and closes the opening.

[0142] The end cap 212 refers to a component that covers the opening of the shell 211 to isolate the internal environment of the cylindrical battery cell 20 from the external environment. Without limitation, the shape of the end cap 212 can be adapted to the shape of the shell 211 to match the shell 211. Optionally, the end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 212 is not easily deformed when squeezed and collided, so that the cylindrical battery cell 20 can have a higher structural strength and improved reliability. The material of the end cap 212 can include but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. The cylindrical battery cell 20 also includes an insulating member, which is arranged on the inner side of the end cap 212. The insulating member can be used to isolate the electrical connection components in the shell 211 from the end cap 212 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc.

[0143] The housing 211 is a component that cooperates with the end cap 212 to form the internal environment of the cylindrical battery cell 20. This internal environment can be used to accommodate the electrode assembly 22, electrolyte, and other components. The housing 211 and the end cap 212 can be separate components. An opening can be provided in the housing 211, and the end cap 212 is placed over the opening to form the internal environment of the cylindrical battery cell 20. Alternatively, the end cap 212 and the housing 211 can be integrated. Specifically, the end cap 212 and the housing 211 can form a common joint surface before other components are inserted into the housing. When the interior of the housing 211 needs to be encapsulated, the end cap 212 is placed over the housing 211. The housing 211 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the housing 211 can be determined based on the specific shape and size of the electrode assembly 22. The materials of the housing 211 can include, but are not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0144] The electrode assembly 22 is a component in the cylindrical battery cell 20 where the electrochemical reaction occurs. One or more electrode assemblies 22 may be contained in the shell 211. The electrode assembly 22 is mainly formed by winding or stacking the positive electrode sheet and the 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 221 of the electrode assembly 22, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute the tab 222. The positive tab and the negative tab may be located together at one end of the main body 221 or respectively at both ends of the main body 221. During the charge and discharge process of the cylindrical battery cell 20, the positive electrode active material and the negative electrode active material react with the electrolyte.

[0145] The first wall portion 213 may be the end cover 212 of the housing 21 or a wall of the shell 211 of the housing 21. Figure 3 and Figure 4 In the embodiment, the first wall portion 213 is the bottom wall 2112 of the housing 211 that is disposed opposite to the end cover 212. In other embodiments, the first wall portion 213 is the end cover 212.

[0146] As an example, in Figure 3 and Figure 4 In the illustrated embodiment, the housing 211 has an opening formed at only one end. A single end cap 212 is provided, sealing the opening of the housing 211. Electrode terminals 23 are provided on the walls of the housing 211 opposing the end cap 212. Tabs 222 are formed at opposite ends of the electrode assembly 22. The tab 222 at one end of the electrode assembly 22 is the positive electrode tab, while the tab 222 at the other end is the negative electrode tab. The electrode terminal 23 is electrically connected to the positive electrode tab via a current collecting member, while the end cap 212 is electrically connected to the negative electrode tab via another current collecting member.

[0147] The first wall portion 213 is provided with a terminal hole 2131, and the terminal hole 2131 penetrates the first wall portion 213 along the thickness direction of the first wall portion 213. In other words, the terminal hole 2131 is a through hole provided in the first wall portion 213. Figure 5 , the thickness direction of the first wall portion 213 may be the X direction shown in the figure.

[0148] The electrode terminal 23 is used to electrically connect to the tab 222 of the electrode assembly 22 to input or output electrical energy from the cylindrical battery cell 20. The electrode terminal 23 and the tab 222 can be directly connected, for example, by direct welding. The electrode terminal 23 and the tab 222 can also be indirectly connected, for example, by indirectly connecting the electrode terminal 23 and the tab 222 through a current collecting member.

[0149] The electrode terminal 23 is mounted on the first wall 213. The location of the electrode terminal 23 can be used to determine which wall of the housing 21 is the first wall 213. For example, if the electrode terminal 23 is mounted on the end cap 212, the end cap 212 is the first wall 213. If the electrode terminal 23 is mounted on the bottom wall 2112 of the housing 211, the bottom wall 2112 is the first wall 213.

[0150] The main body 232 is the main structure of the electrode terminal 23 and is disposed within the terminal hole 2131. Optionally, the main body 232 is a columnar structure. The first stopper 231 is connected to the end of the main body 232 facing the interior of the housing 21. Along the thickness direction of the first wall 213, the first stopper 231 is closer to the electrode assembly 22 than the first wall 213. The first stopper 231 is used to abut against the first wall 213 to prevent the main body 232 from disengaging from the terminal hole 2131 in a direction away from the interior of the housing 21.

[0151] Along the thickness direction of the first wall portion 213, the projection of the first limiting portion 231 onto the first wall portion 213 is located outside the terminal hole 2131, such that the projection of the outer circumferential surface 2321 of the first limiting portion 231 onto the first wall portion 213 surrounds the terminal hole 2131. The first limiting portion 231 can be disc-shaped, with the central axis of the first limiting portion 231 substantially coinciding with the central axis of the terminal hole 2131, and the diameter of the first limiting portion 231 being greater than the diameter of the terminal hole 2131.

[0152] “The hardness of the first limiting portion 231 is 25HV to 70HV” means that the Vickers hardness of the first limiting portion 231 is 25 to 70.

[0153] Vickers hardness refers to using a diamond right pyramid indenter with an angle of 136 degrees between the relative surfaces to press into the surface of the test sample under a specified load, maintaining it for a certain period of time, then removing the load, measuring the diagonal length of the indentation, and then calculating the surface area of ​​the indentation. Finally, the average pressure on the indentation surface area is obtained, which is the Vickers hardness value of the metal, represented by the symbol HV. In actual measurement, no calculation is required. Instead, the measured hardness value is directly obtained by looking up the table based on the measured diagonal length of the indentation. For example, when the hardness of the first limiter 231 is 25HV, a test force of 0.05 kgf can be used, maintained for 10 to 15 seconds, and a hardness value of 25 is obtained.

[0154] The hardness of the first limiting portion 231 can be 25HV, 30HV, 32HV, 35HV, 40HV, 45HV, 50HV, 55HV, 60HV, 62HV, 65HV, 70HV, etc.

[0155] The first stopper 231 prevents the electrode terminal 23 from disengaging from the terminal hole 2131 in a direction away from the electrode assembly 22, thereby reducing the risk of the electrode terminal 23 disengaging from the first wall 213 under the influence of the internal air pressure of the cylindrical battery cell 20. When the hardness of the first stopper 231 is greater than or equal to 25 HV, the first stopper 231 has a relatively high hardness and a correspondingly high yield strength, making it less likely to deform under the influence of the internal air pressure of the cylindrical battery cell 20. This reduces the risk of the electrode terminal 23 disengaging from the first wall 213 under the influence of the internal air pressure of the cylindrical battery cell 20 and improves the reliability of the cylindrical battery cell 20. When the hardness of the first stopper 231 is less than or equal to 70 HV, the hardness of the first stopper 231 is not excessive, thereby facilitating the production of the electrode terminal 23 and reducing the manufacturing cost of the cylindrical battery cell 20. Therefore, when the hardness of the first limiting portion 231 is 25HV to 70HV, it can not only reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20, but also facilitate the production of the electrode terminal 23 and reduce the manufacturing cost of the cylindrical battery cell 20.

[0156] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the hardness of the first limiting portion 231 is 35HV to 50HV.

[0157] The hardness of the first limiting portion 231 can be: 35HV, 36HV, 37HV, 38HV, 39HV, 40HV, 41HV, 42HV, 43HV, 44HV, 45HV, 46HV, 47HV, 48HV, 49HV, 50HV, etc.

[0158] When the hardness of the first limiting portion 231 is greater than or equal to 35 HV, the first limiting portion 231 has a higher hardness and correspondingly a higher yield strength. This makes the first limiting portion 231 less likely to deform under the internal air pressure of the cylindrical battery cell 20, further reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When the hardness of the first limiting portion 231 is less than or equal to 50 HV, the hardness of the first limiting portion 231 is not excessive, thereby facilitating the production of the electrode terminal 23 and reducing the manufacturing cost of the cylindrical battery cell 20. Therefore, when the hardness of the first limiting portion 231 is between 35 HV and 50 HV, the risk of the electrode terminal 23 separating from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20 is further reduced, improving the reliability of the cylindrical battery cell 20, facilitating the production of the electrode terminal 23, and reducing the manufacturing cost of the cylindrical battery cell 20.

[0159] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, along the thickness direction of the first wall portion 213 , the minimum thickness of the first limiting portion 231 is H1, satisfying: 1 mm ≤ H1 ≤ 2.5 mm.

[0160] H1 represents the minimum thickness of the first limiting portion 231 along the thickness direction of the first wall portion 213. During measurement, the narrowest position of the first limiting portion 231 in the thickness direction of the first wall portion 213 can be measured as H1.

[0161] The minimum thickness of the first limiting portion 231 along the thickness direction of the first wall portion 213 can be: H1 = 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, etc.

[0162] When H1 ≥ 1 mm, the minimum thickness of the first limiting portion 231 is relatively thick, and the yield strength of the first limiting portion 231 is relatively high. This reduces the risk of deformation of the first limiting portion 231 under the internal air pressure of the cylindrical battery cell 20, thereby reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When H1 ≤ 2.5 mm, the minimum thickness of the first limiting portion 231 is not excessive, and the thickness of the first limiting portion 231 is not excessive. This not only helps reduce material consumption for the electrode terminal 23 and the cost of the cylindrical battery cell 20, but also helps reduce the internal space occupied by the cylindrical battery cell 20, reducing the weight of the cylindrical battery cell 20 and improving the energy density of the cylindrical battery cell 20. Therefore, when 1 mm ≤ H1 ≤ 2.5 mm, both the reliability and energy density of the cylindrical battery cell 20 are achieved.

[0163] Optionally, 1mm≤H1≤1.5mm.

[0164] The minimum thickness of the first limiting portion 231 along the thickness direction of the first wall portion 213 can be: H1 = 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, etc.

[0165] When H1 ≥ 1 mm, the minimum thickness of the first limiting portion 231 is relatively thick, and the yield strength of the first limiting portion 231 is relatively high. This reduces the risk of deformation of the first limiting portion 231 under the internal air pressure of the cylindrical battery cell 20, thereby reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When H1 ≤ 1.5 mm, the minimum thickness of the first limiting portion 231 is not excessive, and the thickness of the first limiting portion 231 is not excessive. This not only helps reduce material consumption for the electrode terminal 23 and the cost of the cylindrical battery cell 20, but also helps reduce the internal space occupied by the cylindrical battery cell 20, reduce the weight of the cylindrical battery cell 20, and improve the energy density of the cylindrical battery cell 20. Therefore, when 1 mm ≤ H1 ≤ 1.5 mm, the reliability and energy density of the cylindrical battery cell 20 are better balanced.

[0166] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the first limiting portion 231 is disc-shaped. The outer edge diameter of the first limiting portion 231 is D1, and the diameter of the terminal hole 2131 is D2, satisfying: 1.5≤D1 / D2≤2.2.

[0167] The first limiting portion 231 is a disc structure. D1 represents the diameter of the outer edge of the first limiting portion 231. During measurement, multiple measurements can be taken and the average value is taken as D1.

[0168] The terminal hole 2131 is a circular hole, and D2 represents the diameter of the terminal hole 2131 . During measurement, multiple measurements can be taken and the average value is taken as D2 .

[0169] D1 / D2 represents the ratio of the diameter of the outer edge of the first limiting portion 231 to the diameter of the terminal hole 2131 .

[0170] The ratio of the diameter of the outer edge of the first limiting portion 231 to the diameter of the terminal hole 2131 may be: D1 / D2=1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, etc.

[0171] When D1 / D2 ≥ 1.5, the ratio of the diameter of the outer edge of the first retaining portion 231 to the diameter of the terminal hole 2131 is large. Consequently, the portion of the first retaining portion 231 that protrudes beyond the terminal hole 2131 is relatively large, meaning that the area of ​​the first retaining portion 231 opposing the first wall portion 213 is relatively large. This improves the retaining effect of the first retaining portion 231, further reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the influence of the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When D1 / D2 ≤ 2.2, the ratio of the diameter of the outer edge of the first retaining portion 231 to the diameter of the terminal hole 2131 is not excessively large, and the portion of the first retaining portion 231 that protrudes beyond the terminal hole 2131 is not excessively large. Furthermore, the first retaining portion 231 is relatively far from other walls of the housing 21, which reduces the risk of the first retaining portion 231 contacting other walls of the housing 21 and causing a short circuit when the housing 21 deforms. On the other hand, when the first retaining portion 231 is deformed by an external force, it is difficult for the first retaining portion 231 to be inserted into the electrode assembly 22, which prevents the positive and negative electrode tabs from overlapping and causing a short circuit, thereby improving the reliability of the cylindrical battery cell 20. Therefore, when 1.5≤D1 / D2≤2.2, the cylindrical battery cell 20 has high reliability.

[0172] Optionally, 1.8≤D1 / D2≤2.

[0173] The ratio of the diameter of the outer edge of the first limiting portion 231 to the diameter of the terminal hole 2131 can be: D1 / D2=1.8, 1.82, 1.85, 1.88, 1.9, 1.92, 1.95, 1.98, 2, etc.

[0174] When D1 / D2 is ≥ 1.8, the ratio of the diameter of the outer edge of the first retaining portion 231 to the diameter of the terminal hole 2131 is greater. This increases the portion of the first retaining portion 231 that protrudes beyond the terminal hole 2131, meaning that the area of ​​the first retaining portion 231 that opposes the first wall portion 213 is larger. This improves the retaining effect of the first retaining portion 231, further reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the influence of the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When D1 / D2 is ≤ 2, the ratio of the diameter of the outer edge of the first retaining portion 231 to the diameter of the terminal hole 2131 is not excessively large, and the portion of the first retaining portion 231 that protrudes beyond the terminal hole 2131 is not excessively large. Furthermore, the first retaining portion 231 is further away from other walls of the housing 21, further reducing the risk of the first retaining portion 231 contacting other walls of the housing 21 and causing a short circuit when the housing 21 deforms. On the other hand, when the first retaining portion 231 is deformed by an external force, it is less likely to be inserted into the electrode assembly 22, making it less likely that the positive and negative electrode tabs will overlap and short-circuit, thereby improving the reliability of the cylindrical battery cell 20. Therefore, when 1.5 ≤ D1 / D2 ≤ 2.2, the cylindrical battery cell 20 has higher reliability.

[0175] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 , in some embodiments, 24mm≤D1≤36mm.

[0176] The diameter of the outer edge of the first limiting portion 231 can be: D1 = 24 mm, 25 mm, 28 mm, 30 mm, 32 mm, 35 mm, 36 mm, etc.

[0177] When D1 is greater than or equal to 24 mm, the diameter of the outer edge of the first limiting portion 231 is large, which is beneficial to make the part of the first limiting portion 231 exceeding the terminal hole 2131 larger, that is, the area of the first limiting portion 231 opposite to the first wall portion 213 is larger, and the limiting effect of the first limiting portion 231 is better, which is beneficial to reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal gas pressure of the cylindrical battery monomer 20, and improve the reliability of the cylindrical battery monomer 20. When D1 is less than or equal to 36 mm, the diameter of the outer edge of the first limiting portion 231 is not too large, on the one hand, the first limiting portion 231 is far away from other wall portions of the shell 21, when the shell 21 deforms, it is beneficial to reduce the risk of the first limiting portion 231 contacting other wall portions of the shell 21 and causing short circuit. On the other hand, when the first limiting portion 231 deforms under the action of external force, the first limiting portion 231 is not easy to be inserted into the electrode assembly 22, and the positive and negative electrode plates are not easy to be overlapped to cause short circuit, which is beneficial to improve the reliability of the cylindrical battery monomer 20. Therefore, when 24 mm≤D1≤36 mm, the cylindrical battery monomer 20 has higher reliability.

[0178] Optionally, 28 mm≤D1≤34 mm.

[0179] The diameter of the outer edge of the first limiting portion 231 can be: D1=28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 33 mm, 34 mm, etc.

[0180] When D1 is greater than or equal to 28 mm, the diameter of the outer edge of the first limiting portion 231 is larger, which is beneficial to make the part of the first limiting portion 231 exceeding the terminal hole 2131 larger, that is, the area of the first limiting portion 231 opposite to the first wall portion 213 is larger, and the limiting effect of the first limiting portion 231 is better, which is beneficial to reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal gas pressure of the cylindrical battery monomer 20, and improve the reliability of the cylindrical battery monomer 20. When D1 is less than or equal to 34 mm, on the one hand, the first limiting portion 231 is farther away from other wall portions of the shell 21, when the shell 21 deforms, it is more beneficial to reduce the risk of the first limiting portion 231 contacting other wall portions of the shell 21 and causing short circuit. On the other hand, when the first limiting portion 231 deforms under the action of external force, the first limiting portion 231 is more difficult to be inserted into the electrode assembly 22, and the positive and negative electrode plates are more difficult to be overlapped to cause short circuit, which is more beneficial to improve the reliability of the cylindrical battery monomer 20. Therefore, when 24 mm≤D1≤36 mm, the cylindrical battery monomer 20 has higher reliability.

[0181] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6In some embodiments, the diameter of the terminal hole 2131 is D2, and the diameter of the outer surface of the housing 21 is D3, satisfying: 0.28≤D2 / D3≤0.4.

[0182] D3 represents the diameter of the outer surface of the housing 21, that is, the outer diameter of the shell 211. During measurement, multiple measurements can be taken and the average value is taken as D3.

[0183] D2 / D3 represents the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21. The ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 can be: D2 / D3=0.28, 0.3, 0.32, 0.35, 0.38, 0.4, etc.

[0184] When D2 / D3 ≤ 0.4, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is small, and the area of ​​the first wall 213 occupied by the terminal hole 2131 is small. This, on the one hand, allows for a larger area of ​​the remaining portion of the first wall 213, increasing its strength and making it less susceptible to deformation. This helps reduce the risk of the electrode terminal 23 being separated from the first wall 213 by the internal pressure of the cylindrical battery cell 20. On the other hand, when the terminal hole 2131 is small, the electrode terminal 23 is also relatively small, which helps reduce the area of ​​interaction between the internal gas and the electrode terminal 23, thereby reducing the risk of the electrode terminal 23 being separated from the first wall 213 by the internal pressure of the cylindrical battery cell 20. When D2 / D3 ≥ 0.28, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is not too small, thus preventing the electrode terminal 23 from being too small. This, on the one hand, facilitates installation of the electrode terminal 23, and on the other hand, enhances the current carrying capacity of the electrode terminal 23. Therefore, when 0.28≤D2 / D3≤0.4, it is beneficial to reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal air pressure of the cylindrical battery cell 20, and it is also convenient to install the electrode terminal 23, so that the electrode terminal 23 has a stronger current carrying capacity.

[0185] Optionally, 0.32≤D2 / D3≤0.36.

[0186] The ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 may be: D2 / D3=0.32, 0.325, 0.33, 0.335, 0.34, 0.345, 0.35, 0.355, 0.36, etc.

[0187] When D2 / D3 ≤ 0.36, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is smaller, and the area of ​​the first wall portion 213 occupied by the terminal hole 2131 is smaller. This, on the one hand, increases the area of ​​the remaining portion of the first wall portion 213, increases the strength of the first wall portion 213, and makes the first wall portion 213 less susceptible to deformation, thereby reducing the risk of the electrode terminal 23 being separated from the first wall portion 213 under the influence of the internal gas pressure of the cylindrical battery cell 20. On the other hand, when the terminal hole 2131 is smaller, the electrode terminal 23 is also relatively smaller, which helps reduce the area of ​​interaction between the internal gas and the electrode terminal 23, thereby reducing the risk of the electrode terminal 23 being separated from the first wall portion 213 under the influence of the internal gas pressure of the cylindrical battery cell 20. When D2 / D3 ≥ 0.32, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is not too small, so that the electrode terminal 23 is not too small. This, on the one hand, facilitates the installation of the electrode terminal 23, and on the other hand, helps to strengthen the current carrying capacity of the electrode terminal 23. Therefore, when 0.32≤D2 / D3≤0.36, it is beneficial to reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal air pressure of the cylindrical battery cell 20, and it is also convenient to install the electrode terminal 23, so that the electrode terminal 23 has a stronger current carrying capacity.

[0188] In some embodiments, 38 mm ≤ D3 ≤ 80 mm.

[0189] The diameter of the housing 21 can be: D3 = 38mm, 40mm, 44mm, 46mm, 50mm, 54mm, 56mm, 60mm, 64mm, 66mm, 70mm, 74mm, 76mm, 80mm, etc.

[0190] In some embodiments, 14 mm ≤ D2 ≤ 21 mm.

[0191] The diameter of the terminal hole 2131 can be: D2 = 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, etc.

[0192] When D2 ≤ 21 mm, the diameter of the terminal hole 2131 is relatively small, and the electrode terminal 23 is also relatively small, which helps reduce the area of ​​interaction between internal gas and the electrode terminal 23, thereby reducing the risk of the electrode terminal 23 separating from the first wall portion 213 under the influence of the internal air pressure of the cylindrical battery cell 20. When D2 ≥ 14 mm, the diameter of the terminal hole 2131 is not too small, so the electrode terminal 23 is not too small. On the one hand, it can facilitate the installation of the electrode terminal 23, and on the other hand, it can help to strengthen the flow capacity of the electrode terminal 23. Therefore, when 14 mm ≤ D2 ≤ 21 mm, it can help to reduce the risk of the electrode terminal 23 separating from the first wall portion 213 under the influence of the internal air pressure of the cylindrical battery cell 20, and it can also facilitate the installation of the electrode terminal 23, and it can also help to strengthen the flow capacity of the electrode terminal 23.

[0193] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the material of the first wall portion 213 includes steel. The thickness of the first wall portion 213 is H2, which satisfies: 0.4 mm ≤ H2 ≤ 1 mm.

[0194] The material of the first wall portion 213 can be carbon steel or stainless steel, and the carbon steel can be low carbon steel, medium carbon steel or high carbon steel.

[0195] It should be noted that the material of the first wall portion 213 includes at least one of stainless steel and carbon steel. If the first wall portion 213 is the end cover 212 of the outer shell 21, the material of the end cover 212 includes at least one of stainless steel and carbon steel; if the first wall portion 213 is a wall portion in the shell 211, the material of the shell 211 includes at least one of stainless steel and carbon steel.

[0196] In this embodiment, by setting the material of the first wall portion 213 to include at least one of stainless steel and carbon steel, due to the high strength of steel, the first wall portion 213 made of steel has better strength. When the bursting pressure of the cylindrical battery cell 20 is constant, the first wall portion 213 can be made thinner, which is beneficial to saving the space occupied by the first wall portion 213.

[0197] H2 represents the thickness of the first wall portion 213. In some embodiments, the thickness of the first wall portion 213 is uniform. The thickness of the first wall portion 213 is any value between 0.4 and 1 mm. In other embodiments, the thickness of the first wall portion 213 varies, but the minimum thickness of the first wall portion 213 is greater than or equal to 0.4 mm, and the maximum thickness of the first wall portion 213 is less than or equal to 1 mm.

[0198] The thickness of the first wall portion 213 can be: H2 = 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, etc.

[0199] Steel has high strength, effectively enhancing the structural strength of the first wall portion 213. This reduces the risk of deformation of the first wall portion 213 due to stress, and reduces the risk of the electrode terminal 23 detaching from the first wall portion 213 due to the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When H2 ≥ 0.4 mm, the thickness of the first wall portion 213 is greater, resulting in higher structural strength. This reduces the risk of deformation of the first wall portion 213 due to stress, and reduces the risk of the electrode terminal 23 detaching from the first wall portion 213 due to the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When H2 ≤ 1 mm, the thickness of the first wall portion 213 is not excessive, which helps reduce material consumption for the first wall portion 213 and reduces the cost of the cylindrical battery cell 20. Therefore, when 0.4 mm ≤ H2 ≤ 1 mm, both the reliability and cost of the cylindrical battery cell 20 are achieved.

[0200] Optionally, 0.6mm≤H2≤0.8mm.

[0201] The thickness of the first wall portion 213 may be: H2 = 0.6 mm, 0.62 mm, 0.65 mm, 0.68 mm, 0.7 mm, 0.72 mm, 0.75 mm, 0.78 mm, 0.8 mm, etc.

[0202] When H2 ≥ 0.6 mm, the thickness of the first wall portion 213 is greater, providing greater structural strength. This further reduces the risk of deformation of the first wall portion 213 due to stress, and reduces the risk of the electrode terminal 23 detaching from the first wall portion 213 due to the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When H2 ≤ 0.8 mm, the thickness of the first wall portion 213 is not excessively large, further reducing material consumption for the first wall portion 213 and lowering the cost of the cylindrical battery cell 20. Therefore, when 0.6 mm ≤ H2 ≤ 0.8 mm, both the reliability and cost of the cylindrical battery cell 20 are achieved.

[0203] Please refer to Figure 7 and Figure 8 , Figure 7 This is a schematic structural diagram of the electrode terminal 23 provided in some embodiments of the present application. Figure 8A cross-sectional view of an electrode terminal 23 provided in some embodiments of the present application. In some embodiments, the main body 232 has an outer peripheral surface 2321, and the first limiting portion 231 has a first surface 2311 facing the first wall portion 213. The outer peripheral surface 2321 and the first surface 2311 are connected by a chamfered surface 234.

[0204] The outer circumferential surface 2321 of the main body 232 is disposed around the axis of the terminal hole 2131. When the main body 232 is a cylindrical structure, the outer circumferential surface 2321 of the main body 232 is a circular surface.

[0205] The first surface 2311 is the surface of the first limiting portion 231 facing the first wall portion 213 , that is, the surface of the first limiting portion 231 facing away from the electrode assembly 22 .

[0206] The outer peripheral surface 2321 and the first surface 2311 are transitioned by a chamfer. The chamfer has a chamfer surface 234 that connects the outer peripheral surface 2321 and the first surface 2311.

[0207] By connecting the outer peripheral surface 2321 and the first surface 2311 via the chamfered surface 234, a smooth transition can be achieved between the outer peripheral surface 2321 and the first surface 2311, reducing stress concentration and lowering the risk of deformation of the first limiting portion 231 at this location. Furthermore, the chamfered surface can act as a reinforcing rib to a certain extent, further reducing the risk of deformation of the first limiting portion 231.

[0208] Please refer to Figure 7 and Figure 8 In some embodiments, the cross section of the chamfered surface 234 is arc-shaped.

[0209] The cross section of the chamfered surface 234 is a cross section passing through the diameter of the cylindrical battery cell 20. When the cross section of the chamfered surface 234 is an arc shape, the outer peripheral surface 2321 and the first surface 2311 are transitioned through a rounded corner.

[0210] The cross section of the chamfered surface 234 is in an arc shape, and the chamfer is a rounded corner, which can effectively reduce stress concentration.

[0211] Please refer to Figure 9 , Figure 9 The cross-sectional view of the electrode terminal 23 provided in some other embodiments of the present application. In some other embodiments, the cross section of the chamfered surface 234 is linear.

[0212] The cross section of the chamfered surface 234 is a cross section passing through the diameter of the cylindrical battery cell 20. When the cross section of the chamfered surface 234 is a straight line, the outer peripheral surface 2321 and the first surface 2311 transition at an oblique angle.

[0213] The cross section of the chamfered surface 234 is a straight line, and the chamfer is an oblique angle, which can effectively reduce stress concentration.

[0214] Please refer to Figure 9 In some embodiments, along the radial direction of the cylindrical battery cell 20 , the distance from the connection position between the chamfered surface 234 and the first surface 2311 to the outer peripheral surface 2321 is L, which satisfies: 0.1 mm ≤ L ≤ 0.6 mm.

[0215] The radial direction of the cylindrical battery cell 20 is also the linear direction of the diameter or radius of the cylindrical battery cell 20. The radial direction of the cylindrical battery cell 20 is perpendicular to the axial direction of the cylindrical battery cell 20. Figure 9 The radial direction of the cylindrical battery cell 20 is the Y direction shown in the figure.

[0216] L represents the distance from the connection position between the chamfered surface 234 and the first surface 2311 to the outer peripheral surface 2321 along the radial direction of the cylindrical battery cell 20. During measurement, multiple measurements can be taken and the average value is taken as L.

[0217] The distance from the connection position between the chamfered surface 234 and the first surface 2311 to the outer circumferential surface 2321 along the radial direction of the cylindrical battery cell 20 can be: L=0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, etc.

[0218] When L ≥ 0.1 mm, the distance from the connection point between the chamfered surface 234 and the first surface 2311 to the outer circumferential surface 2321 along the radial direction of the cylindrical battery cell 20 is greater, effectively reducing stress concentration and providing a better reinforcement effect. When L ≤ 0.6 mm, the distance from the connection point between the chamfered surface 234 and the first surface 2311 to the outer circumferential surface 2321 along the radial direction of the cylindrical battery cell 20 is not too large, which can reduce the risk of interference with other components. Therefore, when 0.1 mm ≤ L ≤ 0.6 mm, stress concentration can be effectively reduced and interference with other components is less likely.

[0219] Optionally, 0.3mm≤L≤0.5mm.

[0220] The distance from the connection position between the chamfered surface 234 and the first surface 2311 to the outer circumferential surface 2321 along the radial direction of the cylindrical battery cell 20 can be: L=0.3mm, 0.32mm, 0.35mm, 0.38mm, 0.4mm, 0.42mm, 0.45mm, 0.48mm, 0.5mm, etc.

[0221] When L≥0.3mm, the distance from the connection position of the chamfer surface 234 and the first surface 2311 to the outer peripheral surface 2321 in the radial direction of the cylindrical battery cell 20 is greater, the effect of reducing stress concentration is better, and the reinforcing effect is better. When L≤0.5mm, the distance from the connection position of the chamfer surface 234 and the first surface 2311 to the outer peripheral surface 2321 in the radial direction of the cylindrical battery cell 20 is not too great, and the risk of interference with other components can be reduced. Therefore, when 0.3mm≤L≤0.5mm, stress concentration can be effectively reduced, and interference with other components is less likely.

[0222] Please refer to Figure 9 In some embodiments, the angle between the chamfer surface 234 and the first surface 2311 in the cross section of the cylindrical battery cell 20 is C, which satisfies: 125°≤C≤145°. The cross section is parallel to the axial direction of the cylindrical battery cell 20.

[0223] The cross section of the cylindrical battery cell 20 is a cross section passing through the diameter of the cylindrical battery cell 20. The cross section of the cylindrical battery cell 20 is parallel to the axial direction of the cylindrical battery cell 20. Please refer to Figure 9 The axial direction of the cylindrical battery cell 20 is the X direction shown in the figure. In Figure 9 the embodiment shown, the axial direction of the cylindrical battery cell 20 is parallel to the thickness direction of the first wall portion 213.

[0224] In the cross section of the cylindrical battery cell 20, the angle between the chamfer surface 234 and the first surface 2311 can be: C=125°, 126°, 127°, 128°, 129°, 130°, 131°, 132°, 133°, 134°, 135°, 136°, 137°, 138°, 139°, 140°, 141°, 142°, 143°, 144°, 145°, etc.

[0225] When 125°≤C≤145°, the size of the chamfer is moderate, which is conducive to reducing stress concentration and reinforcing to some extent.

[0226] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the electrode terminal 23 includes a second limiting portion 233 connected to one end of the main body portion 232 away from the inside of the housing 21. The second limiting portion 233 cooperates with the first limiting portion 231 to clamp the first wall portion 213.

[0227] The first limiting portion 231 and the second limiting portion 233 are respectively connected to the two ends of the main body 232. The first limiting portion 231 can limit the main body 232 from being separated from the terminal hole 2131 in a direction away from the electrode assembly 22, and the second limiting portion 233 can limit the main body 232 from being separated from the terminal hole 2131 in a direction facing the electrode assembly 22.

[0228] The first limiting portion 231 and the second limiting portion 233 are oppositely arranged along the thickness direction of the first wall portion 213 . The first limiting portion 231 and the second limiting portion 233 can cooperate to clamp the first wall portion 213 to prevent the main body 232 from being separated from the terminal hole 2131 .

[0229] By providing a first limiting portion 231 and a second limiting portion 233 at both ends of the main body 232, the first limiting portion 231 and the second limiting portion 233 can cooperate to clamp the first wall portion 213, thereby restricting the main body 232 within the terminal hole 2131. Specifically, the first limiting portion 231 can restrict the main body 232 from being separated from the terminal hole 2131 in a direction away from the electrode assembly 22, and the second limiting portion 233 can restrict the main body 232 from being separated from the terminal hole 2131 in a direction facing the electrode assembly 22. The first limiting portion 231 and the second limiting portion 233 work together to effectively restrict the main body 232.

[0230] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the diameter of the outer edge of the second limiting portion 233 is smaller than the diameter of the outer edge of the first limiting portion 231 .

[0231] “The diameter of the outer edge of the second limiting portion 233 is smaller than the diameter of the outer edge of the first limiting portion 231 ” means that the maximum diameter of the outer edge of the second limiting portion 233 is smaller than the minimum diameter of the outer edge of the first limiting portion 231 .

[0232] When the outer edge diameter of the second limiting portion 233 is smaller than the outer edge diameter of the first limiting portion 231 , the second limiting portion 233 may be riveted to the first wall portion 213 from the side of the first wall portion 213 facing away from the interior of the housing 21 .

[0233] In other embodiments, the diameter of the outer edge of the second limiting portion 233 is greater than the diameter of the outer edge of the first limiting portion 231 .

[0234] “The diameter of the outer edge of the second limiting portion 233 is greater than the diameter of the outer edge of the first limiting portion 231 ” means that the minimum diameter of the outer edge of the second limiting portion 233 is greater than the maximum diameter of the outer edge of the first limiting portion 231 .

[0235] When the diameter of the outer edge of the second limiting portion 233 is greater than the diameter of the outer edge of the first limiting portion 231, the first limiting portion 231 can be riveted to the first wall portion 213 from the side of the first wall portion 213 facing the inside of the shell 21.

[0236] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the second limiting portion 233 is a riveted portion.

[0237] When the second limiting portion 233 is a riveted portion, the second limiting portion 233 can be riveted to the first wall portion 213 from the side of the first wall portion 213 away from the inside of the shell 21.

[0238] In other embodiments, the first limiting portion 231 is a riveted portion.

[0239] When the first limiting portion 231 is a riveted portion, the first limiting portion 231 can be riveted to the first wall portion 213 from the side of the first wall portion 213 facing the inside of the shell 21.

[0240] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 In some embodiments, the shell 21 includes a housing 211 and an end cover 212, the housing 211 includes a bottom wall 2112 and a side wall 2111, the side wall 2111 is arranged around the bottom wall 2112, one end of the side wall 2111 is connected to the bottom wall 2112, and the other end of the side wall 2111 is closed to form an opening. The end cover 212 closes the opening. The bottom wall 2112 is the first wall portion 213.

[0241] The housing 211 includes the side wall 2111 and the bottom wall 2112 which are integrally formed, that is, the housing 211 is processed by an integral forming process, such as stamping, casting or extrusion forming. The side wall 2111 and the bottom wall 2112 of the housing 211 are of an integral structure. The bottom wall 2112 is disc-shaped, and the side wall 2111 is a peripheral wall. The bottom wall 2112 is connected to one end of the side wall 2111.

[0242] The bottom wall 2112 is the first wall portion 213, and the electrode terminal 23 is arranged on the bottom wall 2112. Therefore, the electrode terminal 23 is convenient to install, and the electrode terminal 23 is accurately installed, so that the stability of the connection between the electrode terminal 23 and the electrode assembly 22 is higher.

[0243] The application also provides a battery device 100, which includes the cylindrical battery cell 20 described above.

[0244] The embodiment of the present application further provides an electrical device, which includes the above-mentioned cylindrical battery cell 20. The cylindrical battery cell 20 is used to provide electrical energy to the electrical device.

[0245] According to some embodiments of this application, please refer to Figures 3 to 9 .

[0246] An embodiment of the present application provides a cylindrical battery cell 20, which includes a housing 21, an electrode assembly 22, and an electrode terminal 23. The housing 21 has a first wall 213, which is provided with a terminal hole 2131. The electrode assembly 22 is accommodated in the housing 21, and the electrode terminal 23 is electrically connected to the electrode assembly 22. The electrode terminal 23 includes a main body 232 and a first stopper 231. The main body 232 is inserted into the terminal hole 2131, and the first stopper 231 is connected to the main body 232. Along the thickness direction of the first wall 213, the first stopper 231 is located on the side of the first wall 213 facing the electrode assembly 22. The first stopper 231 is configured to limit the electrode terminal 23 from disengaging from the terminal hole 2131 in a direction away from the electrode assembly 22. The hardness of the first stopper 231 is 25HV to 70HV. The first stopper 231 prevents the electrode terminal 23 from disengaging from the terminal hole 2131 in a direction away from the electrode assembly 22, thereby reducing the risk of the electrode terminal 23 disengaging from the first wall 213 under the influence of the internal air pressure of the cylindrical battery cell 20. When the hardness of the first stopper 231 is greater than or equal to 25 HV, the first stopper 231 has a relatively high hardness and a correspondingly high yield strength, making it less likely to deform under the influence of the internal air pressure of the cylindrical battery cell 20. This reduces the risk of the electrode terminal 23 disengaging from the first wall 213 under the influence of the internal air pressure of the cylindrical battery cell 20 and improves the reliability of the cylindrical battery cell 20. When the hardness of the first stopper 231 is less than or equal to 70 HV, the hardness of the first stopper 231 is not excessive, thereby facilitating the production of the electrode terminal 23 and reducing the manufacturing cost of the cylindrical battery cell 20. Therefore, when the hardness of the first limiting portion 231 is 25HV to 70HV, it can not only reduce the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20, but also facilitate the production of the electrode terminal 23 and reduce the manufacturing cost of the cylindrical battery cell 20.

[0247] The hardness of the first limiting portion 231 is 35HV to 50HV. When the hardness of the first limiting portion 231 is greater than or equal to 35HV, the hardness of the first limiting portion 231 is greater, and the first limiting portion 231 accordingly has a higher yield strength, making the first limiting portion 231 less likely to deform under the internal air pressure of the cylindrical battery cell 20. This further reduces the risk of the electrode terminal 23 detaching from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When the hardness of the first limiting portion 231 is less than or equal to 50HV, the hardness of the first limiting portion 231 is not too high, thereby facilitating the production of the electrode terminal 23 and reducing the manufacturing cost of the cylindrical battery cell 20. Therefore, when the hardness of the first limiting portion 231 is 35HV to 50HV, the risk of the electrode terminal 23 being separated from the first wall portion 213 under the action of the internal air pressure of the cylindrical battery cell 20 can be further reduced, thereby improving the reliability of the cylindrical battery cell 20, and facilitating the production of the electrode terminal 23, thereby reducing the manufacturing cost of the cylindrical battery cell 20.

[0248] Along the thickness direction of the first wall portion 213, the minimum thickness of the first limiting portion 231 is H1, satisfying the following conditions: 1 mm ≤ H1 ≤ 2.5 mm. When H1 ≥ 1 mm, the minimum thickness of the first limiting portion 231 is relatively thick, and the yield strength of the first limiting portion 231 is relatively high. This reduces the risk of deformation of the first limiting portion 231 under the internal air pressure of the cylindrical battery cell 20, thereby reducing the risk of the electrode terminal 23 being separated from the first wall portion 213 under the internal air pressure of the cylindrical battery cell 20 and improving the reliability of the cylindrical battery cell 20. When H1 ≤ 2.5 mm, the minimum thickness of the first limiting portion 231 is not excessive, and the thickness of the first limiting portion 231 is not excessive. This not only helps reduce material consumption for the electrode terminal 23 and the cost of the cylindrical battery cell 20, but also helps reduce the internal space occupied by the cylindrical battery cell 20, reducing the weight of the cylindrical battery cell 20 and increasing the energy density of the cylindrical battery cell 20. Therefore, when 1 mm ≤ H1 ≤ 2.5 mm, both the reliability of the cylindrical battery cell 20 and the energy density of the cylindrical battery cell 20 can be achieved.

[0249] The first retaining portion 231 is disc-shaped. The outer edge diameter of the first retaining portion 231 is D1, and the diameter of the terminal hole 2131 is D2, satisfying the following relationship: 1.5≤D1 / D2≤2.2. When D1 / D2≥1.5, the ratio of the outer edge diameter of the first retaining portion 231 to the diameter of the terminal hole 2131 is large. This results in a larger portion of the first retaining portion 231 extending beyond the terminal hole 2131, i.e., a larger area of ​​the first retaining portion 231 relative to the first wall portion 213. This improves the retaining effect of the first retaining portion 231, further reducing the risk of the electrode terminal 23 being separated from the first wall portion 213 by the internal air pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When D1 / D2 ≤ 2.2, the ratio of the outer edge diameter of the first limiting portion 231 to the diameter of the terminal hole 2131 is not excessively large, and the portion of the first limiting portion 231 that protrudes beyond the terminal hole 2131 is not excessively large. On the one hand, the first limiting portion 231 is relatively far from other walls of the housing 21, which helps reduce the risk of the first limiting portion 231 contacting other walls of the housing 21 and causing a short circuit when the housing 21 deforms. On the other hand, when the first limiting portion 231 deforms under the action of external forces, the first limiting portion 231 is less likely to be inserted into the electrode assembly 22, preventing the positive and negative electrode tabs from overlapping and causing a short circuit, thereby improving the reliability of the cylindrical battery cell 20. Therefore, when 1.5 ≤ D1 / D2 ≤ 2.2, the cylindrical battery cell 20 has higher reliability.

[0250] The diameter of the terminal hole 2131 is D2, and the diameter of the outer surface of the housing 21 is D3, satisfying the following: 0.28 ≤ D2 / D3 ≤ 0.4. When D2 / D3 ≤ 0.4, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is small, and the area of ​​the first wall 213 occupied by the terminal hole 2131 is small. On the one hand, the remaining area of ​​the first wall 213 is larger, the first wall 213 is stronger, and the first wall 213 is less likely to deform, which helps reduce the risk of the electrode terminal 23 being separated from the first wall 213 due to the internal pressure of the cylindrical battery cell 20. On the other hand, when the terminal hole 2131 is smaller, the electrode terminal 23 is also relatively smaller, which helps reduce the area of ​​interaction between the internal gas and the electrode terminal 23, thereby reducing the risk of the electrode terminal 23 being separated from the first wall 213 due to the internal pressure of the cylindrical battery cell 20. When D2 / D3 ≥ 0.28, the ratio of the diameter of the terminal hole 2131 to the diameter of the outer surface of the housing 21 is not too small, so that the electrode terminal 23 is not too small. On the one hand, it can facilitate the installation of the electrode terminal 23, and on the other hand, it is conducive to strengthening the flow capacity of the electrode terminal 23. Therefore, when 0.28 ≤ D2 / D3 ≤ 0.4, it is conducive to reducing the risk of the electrode terminal 23 being separated from the first wall portion 213 due to the internal air pressure of the cylindrical battery cell 20, and it is also convenient to install the electrode terminal 23, and it is conducive to strengthening the flow capacity of the electrode terminal 23.

[0251] The first wall portion 213 is made of steel, and has a thickness H2 that satisfies the following conditions: 0.4 mm ≤ H2 ≤ 1 mm. Steel has high strength, effectively enhancing the structural strength of the first wall portion 213 , reducing the risk of deformation of the first wall portion 213 due to stress, and reducing the risk of the electrode terminal 23 detaching from the first wall portion 213 due to the internal pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When H2 ≥ 0.4 mm, the first wall portion 213 is thicker and has higher structural strength, reducing the risk of deformation of the first wall portion 213 due to stress, and reducing the risk of the electrode terminal 23 detaching from the first wall portion 213 due to the internal pressure of the cylindrical battery cell 20, thereby improving the reliability of the cylindrical battery cell 20. When H2 ≤ 1 mm, the thickness of the first wall portion 213 is not excessively large, thereby reducing material consumption for the first wall portion 213 and lowering the cost of the cylindrical battery cell 20. Therefore, when 0.4 mm ≤ H2 ≤ 1 mm, both the reliability and the cost of the cylindrical battery cell 20 can be achieved.

[0252] The main body 232 has an outer peripheral surface 2321. The first stopper 231 has a first surface 2311 facing the first wall 213. The outer peripheral surface 2321 and the first surface 2311 are connected by a chamfered surface 234. The chamfered surface 234 connects the outer peripheral surface 2321 and the first surface 2311, creating a smooth transition between the outer peripheral surface 2321 and the first surface 2311, reducing stress concentration and lowering the risk of deformation of the first stopper 231 at this location. Furthermore, the chamfer acts as a reinforcing rib to a certain extent, further reducing the risk of deformation of the first stopper 231.

[0253] The electrode terminal 23 includes a second retaining portion 233 connected to the end of the main body 232 facing away from the interior of the housing 21. The second retaining portion 233 cooperates with the first retaining portion 231 to clamp the first wall portion 213. By providing the first retaining portion 231 and the second retaining portion 233 at each end of the main body 232, the first retaining portion 231 and the second retaining portion 233 cooperate to clamp the first wall portion 213, thereby confining the main body 232 within the terminal aperture 2131. The first retaining portion 231 restricts the main body 232 from disengaging from the terminal aperture 2131 in a direction away from the electrode assembly 22, while the second retaining portion 233 restricts the main body 232 from disengaging from the terminal aperture 2131 in a direction facing the electrode assembly 22. The first retaining portion 231 and the second retaining portion 233 work together to effectively retain the main body 232.

[0254] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A cylindrical battery cell, characterized in that: include: The housing has a first wall portion, wherein the first wall portion is provided with a terminal hole; an electrode assembly housed in the housing; an electrode terminal electrically connected to the electrode assembly, the electrode terminal comprising a main body and a first limiting portion, the main body being disposed through the terminal hole, the first limiting portion being connected to the main body and being located on a side of the first wall facing the electrode assembly along a thickness direction of the first wall, the first limiting portion being configured to limit the electrode terminal from escaping from the terminal hole in a direction away from the electrode assembly; Wherein, the hardness of the first limiting portion is 25HV to 70HV.

2. The cylindrical battery cell according to claim 1, characterized in that: The hardness of the first limiting portion is 35HV to 50HV.

3. The cylindrical battery cell according to claim 1, characterized in that: Along the thickness direction of the first wall portion, the minimum thickness of the first limiting portion is H1, which satisfies: 1 mm ≤ H1 ≤ 2.5 mm.

4. The cylindrical battery cell according to claim 3, characterized in that: 1mm≤H1≤1.5mm.

5. The cylindrical battery cell according to claim 1, characterized in that: The first limiting portion is disc-shaped, the outer edge of the first limiting portion has a diameter D1, and the terminal hole has a diameter D2, satisfying the following relationship: 1.5≤D1 / D2≤2.

2.

6. The cylindrical battery cell according to claim 5, characterized in that: 1.8≤D1 / D2≤2.

7. The cylindrical battery cell according to claim 5, characterized in that: 24mm≤D1≤36mm.

8. The cylindrical battery cell according to claim 7, characterized in that: 28mm≤D1≤34mm.

9. The cylindrical battery cell according to claim 1, characterized in that: The diameter of the terminal hole is D2, and the diameter of the outer surface of the housing is D3, which satisfies: 0.28≤D2 / D3≤0.

4.

10. The cylindrical battery cell according to claim 9, characterized in that: 0.32≤D2 / D3≤0.

36.

11. The cylindrical battery cell according to claim 9, characterized in that: 38mm≤D3≤80mm.

12. The cylindrical battery cell according to any one of claims 5 to 11, characterized in that: 14mm≤D2≤21mm.

13. The cylindrical battery cell according to any one of claims 1 to 11, characterized in that: The material of the first wall portion includes steel, and the thickness of the first wall portion is H2, which satisfies the following: 0.4 mm ≤ H2 ≤ 1 mm.

14. The cylindrical battery cell according to claim 13, characterized in that: 0.6mm≤H2≤0.8mm.

15. The cylindrical battery cell according to any one of claims 1 to 11, characterized in that: The main body has an outer peripheral surface, the first limiting portion has a first surface facing the first wall portion, and the outer peripheral surface and the first surface are connected by a chamfered surface.

16. The cylindrical battery cell according to claim 15, characterized in that: The cross section of the chamfered surface is arc-shaped.

17. The cylindrical battery cell according to claim 15, characterized in that: The cross section of the chamfered surface is linear.

18. The cylindrical battery cell according to claim 17, characterized in that: Along the radial direction of the cylindrical battery cell, a distance L from a connection position between the chamfered surface and the first surface to the outer peripheral surface satisfies: 0.1 mm ≤ L ≤ 0.6 mm.

19. The cylindrical battery cell according to claim 18, characterized in that: 0.3mm≤L≤0.5mm.

20. The cylindrical battery cell according to claim 17, characterized in that: In the cross section of the cylindrical battery cell, the included angle between the chamfered surface and the first surface is C, which satisfies: 125°≤C≤145°, and the cross section is parallel to the axial direction of the cylindrical battery cell.

21. The cylindrical battery cell according to any one of claims 1 to 11, characterized in that: The electrode terminal includes a second limiting portion connected to an end of the main body facing away from the interior of the shell, and the second limiting portion cooperates with the first limiting portion to clamp the first wall portion.

22. The cylindrical battery cell according to claim 21, characterized in that: The diameter of the outer edge of the second limiting portion is smaller than the diameter of the outer edge of the first limiting portion.

23. The cylindrical battery cell according to claim 21, characterized in that: The diameter of the outer edge of the second limiting portion is greater than the diameter of the outer edge of the first limiting portion.

24. The cylindrical battery cell according to claim 21, characterized in that: The second limiting portion is a riveted portion formed by riveting.

25. The cylindrical battery cell according to claim 21, characterized in that: The first limiting portion is a riveted portion formed by riveting.

26. The cylindrical battery cell according to any one of claims 1 to 11, characterized in that: The housing comprises: The housing comprises a bottom wall and a side wall, wherein the side wall is disposed around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall is enclosed to form an opening; an end cap for closing the opening; Wherein, the bottom wall is the first wall portion.

27. A battery device, characterized in that: The invention comprises a cylindrical battery cell according to any one of claims 1 to 26.

28. An electrical device, characterized in that: The cylindrical battery cell comprises the cylindrical battery cell according to any one of claims 1 to 26, and the cylindrical battery cell is used to provide electrical energy to the electrical device.

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