Cylindrical battery monomer, battery and electric equipment

Abstract

The utility model provides a cylindrical battery monomer, a battery and electric equipment. The cylindrical battery cell includes a housing having a first wall portion provided with a terminal hole, and an electrode terminal. The electrode terminal comprises a main body part and a first limiting part, the main body part is arranged in the terminal hole in a penetrating mode, and the first limiting part is connected to the main body part. The first limiting part is located on the side, facing the interior of the shell, of the first wall part in the thickness direction of the first wall part, and the first limiting part can limit the main body part to be separated from the terminal hole in the direction away from the interior of the shell. The projection of the peripheral surface of the first limiting part on the first wall part is arranged around the terminal hole in the thickness direction of the first wall part, the minimum distance between the peripheral surface and the hole wall surface of the terminal hole is A in the radial direction of the terminal hole, the radius of the shell is R, and A / R is larger than or equal to 0.06 and smaller than or equal to 0.24. When A / R is greater than or equal to 0.06 and less than or equal to 0.24, the risk that the electrode terminal is separated from the first wall part under the action of internal air pressure of the battery monomer can be reduced, and the reliability of the battery monomer is improved.

Description

Technical Field

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

[0002] Batteries are widely used in the field of new energy, such as electric vehicles and new energy vehicles. New energy vehicles and electric vehicles have become a new trend in the development of the automotive industry. The development of battery technology must consider many design factors at the same time, such as battery life, energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, the reliability of the battery must also be considered. However, the reliability of current batteries is poor. Utility Model Content

[0003] The purpose of the embodiments of the present application is to provide a cylindrical battery cell, a battery 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 an outer shell and an electrode terminal, the outer shell having a first wall portion, the first wall portion being provided with a terminal hole; the electrode terminal including a main body portion and a first limiting portion, the main body portion being inserted through the terminal hole, the first limiting portion being 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 interior of the outer shell, and the first limiting portion is configured to limit the main body portion from escaping from the terminal hole in a direction away from the interior of the outer shell; wherein, along the thickness direction of the first wall portion, the projection of the outer circumferential surface of the first limiting portion on the first wall portion is arranged around the terminal hole, and along the radial direction of the terminal hole, the minimum distance between the outer circumferential surface and the hole wall surface of the terminal hole is A, and the radius of the outer shell is R, satisfying: 0.06≤A / R≤0.24.

[0005] In the above technical solution, the first limiting portion can prevent the main body from detaching from the terminal hole in the direction away from the inside of the shell, reducing the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the battery cell. When A / R≥0.06, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is large, the relative area of ​​the first limiting portion and the first wall is large, and the limiting effect of the first limiting portion is good, which further reduces the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the battery cell, and improves the reliability of the battery cell. When A / R≤0.24, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 0.06≤A / R≤0.24, it is possible to take into account both the reliability and cost of the battery cell. In addition, the larger the radius of the shell, the larger the area of ​​the first wall portion, the easier it is for the first wall portion to deform under the action of the internal air pressure, and the easier it is for the electrode terminal to detach from the first wall portion. Therefore, when the radius of the shell increases or decreases, the minimum distance between the outer peripheral surface and the hole wall of the terminal hole can be increased or decreased accordingly to reduce the risk of the electrode terminal detaching from the first wall portion under the action of the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell.

[0006] As an optional technical solution of an embodiment of the present application, 0.08≤A / R≤0.19.

[0007] In the above technical solution, when A / R≥0.08, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is larger, the relative area between the first limiting portion and the first wall is larger, and the limiting effect of the first limiting portion is better, which can further reduce the risk of the electrode terminal being separated from the first wall under the action of the internal air pressure of the battery cell, and improve the reliability of the battery cell. When A / R≤0.19, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 0.08≤A / R≤0.19, it is possible to better take into account the reliability and cost of the battery cell.

[0008] As an optional technical solution of an embodiment of the present application, 3mm≤A≤11mm, optionally, 3.9mm≤A≤8.65mm.

[0009] In the above technical solution, when A≥3mm, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is larger, the relative area between the first limiting portion and the first wall is larger, and the limiting effect of the first limiting portion is better, which further reduces the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the battery cell, and improves the reliability of the battery cell. When A≤11mm, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 3mm≤A≤11mm, it is possible to take into account both the reliability and cost of the battery cell.

[0010] When A≥3.9mm, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is larger, the relative area between the first limiting portion and the first wall is larger, and the limiting effect of the first limiting portion is better, which can further reduce the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the battery cell, and improve the reliability of the battery cell. When A≤8.65mm, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 3.9mm≤A≤8.65mm, it is possible to better take into account the reliability and cost of the battery cell.

[0011] As an optional technical solution of the embodiment of the present application, 19mm≤R≤40mm.

[0012] As an optional technical solution of an embodiment of the present application, along the thickness direction of the first wall portion, the minimum thickness of the first limiting portion is H, satisfying: 0.4mm≤H≤2mm, optionally, 0.8mm≤H≤1.6mm.

[0013] In the above technical solution, when H≥0.4mm, the minimum thickness of the first limit portion is thicker, the strength of the first limit portion is greater, the risk of the first limit portion breaking is reduced, the risk of the electrode terminal being separated from the first wall portion under the action of the internal air pressure of the battery cell is reduced, and the reliability of the battery cell is improved. When H≤2mm, the thickness of the first limit portion is not too large, and the thickness of the first limit portion is not too thick, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 0.4mm≤H≤2mm, both the reliability of the battery cell and the energy density of the battery cell can be taken into account.

[0014] When H≥0.8mm, the minimum thickness of the first limit portion is thicker, the strength of the first limit portion is greater, the risk of the first limit portion breaking is further reduced, and the risk of the electrode terminal detaching from the first wall portion under the internal air pressure of the battery cell is further reduced, thereby improving the reliability of the battery cell. When H≤2mm, the thickness of the first limit portion is not too large, and the thickness of the first limit portion is not too thick, which is not only conducive to reducing the material consumption of the electrode terminal and the cost of the battery cell, but also conducive to reducing the occupation of the internal space of the battery cell, reducing the weight of the battery cell, and improving the energy density of the battery cell. Therefore, when 0.4mm≤H≤2mm, it is more possible to take into account both the reliability of the battery cell and the energy density of the battery cell.

[0015] As an optional technical solution of the embodiment of the present application, the material of the electrode terminal is aluminum.

[0016] In the above technical solution, by selecting aluminum as the material of the electrode terminal, it is convenient to weld the electrode terminal to the positive electrode current collecting component or the positive electrode tab.

[0017] As an optional technical solution of an embodiment of the present application, the electrode terminal includes a second limiting portion, the second limiting portion is connected to an end of the main body away from the interior of the shell, and the second limiting portion cooperates with the first limiting portion to clamp the first wall portion.

[0018] In the above technical solution, by respectively providing the first limiting part and the second limiting part at both ends of the main body, the first limiting part and the second limiting part can cooperate to clamp the first wall part, thereby limiting the main body in the terminal hole. The first limiting part can limit the main body from escaping from the terminal hole in the direction facing the inside of the shell, and the second limiting part can limit the main body from escaping from the terminal hole in the direction away from the inside of the shell. The first limiting part and the second limiting part work together to have a good limiting effect on the main body.

[0019] As an optional technical solution of the embodiment of the present application, the electrode terminal is provided with a liquid injection hole, and the liquid injection hole is used to inject electrolyte into the shell.

[0020] In the above technical solution, by providing the injection hole on the electrode terminal, it is helpful to reduce the area occupied by the injection hole on the first wall portion, which is helpful to reduce the volume of the cylindrical battery cell.

[0021] As an optional technical solution of an embodiment of the present application, the shell includes a shell and an end cover, one end of the shell has an opening, and the end cover closes the opening; wherein the shell includes the first wall portion.

[0022] In the above technical solution, when the shell includes the first wall portion, the electrode terminal is arranged on the shell, which facilitates the electrical connection between the electrode assembly and the electrode terminal during manufacturing.

[0023] As an optional technical solution of an embodiment of the present application, 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 the opening; wherein the bottom wall is the first wall portion.

[0024] 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.

[0025] As an optional technical solution of an embodiment of the present application, the cylindrical battery cell includes an electrode assembly, which is accommodated in the shell; the shell includes a second wall portion and a side wall, the second wall portion is arranged at one end of the side wall along the axial direction of the cylindrical battery cell, the side wall is a cylindrical structure and is arranged around the second wall portion, and a first guide channel is formed between the electrode ear of the electrode assembly facing the second wall portion and the side wall; wherein the second wall portion includes a wall body and a supporting portion, the wall body is provided with a pressure relief mechanism, the supporting portion is arranged around the outer edge of the wall body, along the axial direction of the cylindrical battery cell, the supporting portion protrudes from the wall body in a direction close to the electrode assembly, and directly or indirectly abuts against the electrode assembly, the supporting portion and the wall body jointly define a guide space, the supporting portion is provided with a second guide channel, and the second guide channel connects the guide space and the first guide channel.

[0026] In the above technical solution, the abutting portion of the second wall portion abuts against the electrode assembly directly or indirectly, and the abutting portion can play a limiting role on the electrode assembly, reducing the risk of the electrode assembly moving along the axial direction of the cylindrical battery cell in the housing. Since the abutting portion is provided with a second guide channel, the second guide channel connects the guide space and the first guide channel. When the battery cell is thermally runaway, the emissions generated by the electrode assembly flow into the first guide channel. The emissions can flow quickly into the guide space through the second guide channel on the abutting portion, so that the air pressure in the guide space rises rapidly to quickly reach the bursting pressure of the pressure relief mechanism, shortening the time from the thermal runaway of the battery cell to the pressure relief of the battery cell through the pressure relief mechanism, so that the pressure relief mechanism can be actuated in time, reducing the risk of explosion and fire of the battery cell, and effectively improving the reliability of the battery cell. In addition, precisely because the pressure relief mechanism can be activated in time, the emissions generated by the electrode assembly are not easily retained in the cylindrical battery cell, and the internal air pressure of the cylindrical battery cell is not too high, thereby reducing the risk of the electrode terminal detaching from the first wall portion under the action of the internal air pressure of the cylindrical battery cell, thereby improving the reliability of the cylindrical battery cell.

[0027] As an optional technical solution of the embodiment of the present application, the abutting portion is provided with a plurality of the second flow guiding channels, and the plurality of the second flow guiding channels are arranged at intervals along the circumference of the cylindrical battery cell.

[0028] In the above technical solution, by providing a plurality of second guide channels spaced apart along the circumference of the cylindrical battery cell, the emissions in the first guide channel can enter the guide space from the plurality of second guide channels at different positions, thereby increasing the rate at which the emissions in the first guide channel enter the guide space, and further shortening the time from thermal runaway of the battery cell to the start of pressure relief of the battery cell through the pressure relief mechanism.

[0029] As an optional technical solution of an embodiment of the present application, the abutment portion has a abutment surface along the axial direction of the cylindrical battery cell, and the abutment surface is the surface of the abutment portion closest to the electrode assembly, and the second guide channel is a notch groove that penetrates the abutment portion along the radial direction of the cylindrical battery cell and extends along the axial direction of the cylindrical battery cell to the abutment surface.

[0030] In the above technical solution, the second guide channel is a notch groove that penetrates the abutment portion along the radial direction of the cylindrical battery cell and extends to the abutment surface along the axial direction of the cylindrical battery cell. On the one hand, it can reduce the difficulty of forming the second guide channel. On the other hand, it is beneficial to increase the axial size of the second guide channel along the cylindrical battery cell and increase the rate at which the emissions in the first guide channel enter the guide space through the second guide channel.

[0031] As an optional technical solution of an embodiment of the present application, the abutting portion includes a plurality of protrusions, and the plurality of protrusions directly or indirectly abut against the electrode assembly, and a second guide channel is formed between two adjacent protrusions along the circumference of the cylindrical battery cell.

[0032] In the above technical solution, by forming a second guide channel between two adjacent protrusions, the discharge in the first guide channel can enter the guide space from multiple second guide channels at different positions, thereby increasing the rate at which the discharge in the first guide channel enters the guide space. In addition, the second guide channel of this structure is a notch groove formed on the abutment portion, which can reduce the difficulty of forming the second guide channel and is conducive to increasing the size of the second guide channel along the axial direction of the cylindrical battery cell.

[0033] As an optional technical solution of the embodiment of the present application, a flow guiding gap is formed between the side wall and the protruding portion, and the flow guiding gap connects two adjacent second flow guiding channels.

[0034] In the above technical solution, the guide gap between the side wall and the protrusion can connect two adjacent second guide channels. When the emissions in the first guide channel flow toward one of the second guide channels, the emissions can flow toward another adjacent second guide channel through the guide gap, so that the emissions in the first guide channel can enter the guide space more quickly.

[0035] As an optional technical solution of an embodiment of the present application, the abutment portion also includes a main body portion, which is arranged around the outer edge of the wall body and protrudes from the wall body in a direction close to the electrode assembly. Along the axial direction of the cylindrical battery cell, the main body portion has a first surface facing the electrode assembly, and the protruding portion protrudes from the first surface.

[0036] In the above technical solution, the main body serves to connect the wall body and the protruding portion. The main body is arranged around the wall body and protrudes from the wall body in a direction close to the electrode assembly, which can effectively improve the deformation resistance of the end wall.

[0037] As an optional technical solution of an embodiment of the present application, along the axial direction of the cylindrical battery cell, the wall body has a second surface, the second surface is the surface of the wall body closest to the electrode assembly, and the first surface is closer to the electrode assembly than the second surface.

[0038] In the above technical solution, by making the first surface closer to the electrode assembly than the second surface, the distance between the second surface and the electrode assembly can be increased, thereby reducing the impact of the electrode assembly on the pressure relief mechanism on the wall body and effectively increasing the axial size of the guide space along the cylindrical battery cell.

[0039] As an optional technical solution of an embodiment of the present application, the abutment portion is provided with a first groove; along the axial direction of the cylindrical battery cell, the main body portion has a third surface arranged opposite to the first surface, the first surface is closer to the electrode assembly than the third surface, and the first groove is recessed from the third surface toward the direction close to the electrode assembly to form the protrusion protruding from the first surface on the side of the main body portion facing the electrode assembly.

[0040] In the above technical solution, the protrusion is formed correspondingly by providing the first groove on the abutting portion, which can effectively reduce the difficulty of forming the protrusion and the weight of the end wall.

[0041] As an optional technical solution of an embodiment of the present application, the first groove is a multi-level groove, and along the axial direction of the cylindrical battery cell, the first-level groove close to the electrode assembly in two adjacent grooves is arranged on the groove bottom surface of the first-level groove away from the electrode assembly.

[0042] In the above technical solution, by setting the first groove as a multi-stage groove, the second wall portion is subjected to lower forming force when forming each stage of the groove, thereby reducing the risk of the second wall portion being damaged due to excessive forming force when forming the first groove.

[0043] As an optional technical solution of an embodiment of the present application, the protrusion includes a first part and a second part, and the multi-level groove includes a first-level groove and a second-level groove, the first-level groove is recessed from the third surface toward the direction close to the electrode assembly to form the first part protruding from the first surface on the side of the main body facing the electrode assembly, and along the axial direction of the cylindrical battery cell, the first part has a fourth surface facing the electrode assembly; the second-level groove is recessed from the bottom surface of the first-level groove toward the direction close to the electrode assembly to form the second part protruding from the fourth surface on the side of the first part facing the electrode assembly.

[0044] In the above technical solution, the first part of the protrusion can be formed by setting a first-level groove on the main body, and the second part of the protrusion can be formed by setting a second-level groove on the first part, which can reduce the difficulty of forming the protrusion.

[0045] As an optional technical solution of an embodiment of the present application, along the radial direction of the cylindrical battery cell, the first part has a first side surface facing the inner circumferential surface of the side wall, and the second part has a second side surface facing the inner circumferential surface of the side wall, the first side surface is closer to the inner circumferential surface of the side wall than the second side surface, and a flow guide gap is formed between the second side surface and the inner circumferential surface of the side wall, and the flow guide gap connects two adjacent second flow guide channels.

[0046] In the above technical solution, the guide gap between the second side surface and the inner circumferential surface of the side wall can connect two adjacent second guide channels. When the emissions in the first guide channel flow toward a certain second guide channel, the emissions can flow through the guide gap to another adjacent second guide channel, so that the emissions in the first guide channel can enter the guide space more quickly.

[0047] As an optional technical solution of an embodiment of the present application, the battery cell also includes a current collecting member, which is arranged between the second wall portion and the electrode assembly along the axial direction of the cylindrical battery cell, the current collecting member electrically connects the electrode assembly and the second wall portion, the abutting portion directly abuts against the current collecting member, and the current collecting member directly abuts against the electrode assembly.

[0048] In the above technical solution, the electrical connection between the electrode assembly and the second wall portion can be achieved through the current collecting component, thereby reducing the difficulty of the electrical connection between the electrode assembly and the second wall portion.

[0049] In a second aspect, an embodiment of the present application further provides a battery, which includes the above-mentioned cylindrical battery cell.

[0050] In a third aspect, an embodiment of the present application further provides an electrical device, wherein the electrical device comprises the above-mentioned cylindrical battery cell, and the cylindrical battery cell is used to provide electrical energy to the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. 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 related drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0053] Figure 2 An exploded view of a battery provided for some embodiments of the present application;

[0054] Figure 3 An exploded view of a cylindrical battery cell provided in some embodiments of the present application;

[0055] Figure 4 for Figure 3 A cross-sectional view of a cylindrical battery cell is shown;

[0056] Figure 5 for Figure 4 An enlarged view of the upper end of a cylindrical battery cell is shown;

[0057] Figure 6 for Figure 4 An enlarged view of the lower end of a cylindrical battery cell is shown;

[0058] Figure 7 for Figure 6 A schematic structural diagram of the second wall portion shown;

[0059] Figure 8 for Figure 7 AA cross-sectional view of the second wall portion shown;

[0060] Fig. 9 A partial enlarged view of a cylindrical battery cell provided in some other embodiments of the present application;

[0061] Fig.10 for Fig. 9 A partial enlarged view of point C in the middle;

[0062] Fig.11 for Fig. 9 A schematic structural diagram of the second wall portion shown;

[0063] Fig.12 for Fig.11 DD cross-sectional view of the second wall portion is shown.

[0064] Icons: 1-housing; 11-housing; 12-end cover; 13-second wall; 131-wall body; 1311-second surface; 1313-sixth surface; 132-abutment portion; 1321-second flow guide channel; 1322-abutment surface; 1323-protrusion; 13233-first part; 13233a-fourth surface; 13233b-first side; 13234-second part; 13234a-second side; 1324-body; 13241-first surface; 13242-third surface; 1325-first groove; 13251-first level groove; 132 52-second-stage groove; 133-flow guide space; 14-side wall; 141-inner circumference; 15-bottom wall; 16-first wall; 2-electrode assembly; 21-ear; 22-main body; 23-first center hole; 3-electrode terminal; 31-main body; 32-first limit part; 33-second limit part; 4-current collecting member; 41-second center hole; 5-pressure relief mechanism; 6-first flow guide channel; 7-flow guide gap; 10-cylindrical battery cell; 20-casing; 201-first casing; 202-second casing; 100-battery; 200-controller; 300-motor; 1000-vehicle. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0066] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. 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 and secondary relationship.

[0067] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0068] In the description of the present 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.

[0069] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0070] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0071] The term "plurality" used in the present application refers to two or more (including two).

[0072] In the embodiment of the present application, the cylindrical battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating the active material by charging after the battery cell is discharged.

[0073] 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, and the like.

[0074] Cylindrical battery cells generally include an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the cylindrical battery cell, active ions (such as lithium ions) are embedded and removed back and forth between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode, which can reduce the risk of short circuit between the positive and negative electrodes, while allowing active ions to pass through.

[0075] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet 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.

[0076] 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 disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0077] 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 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.).

[0078] 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 positive electrode active materials for batteries can also be used. These positive electrode active materials can 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 / 3 O2 (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 its modified compounds, etc.

[0079] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0080] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0081] As an example, the negative electrode current collector may be a metal foil, a foamed metal or a composite current collector. For example, as the metal foil, aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc., treated with silver surface, may be used. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. The composite current collector may include a polymer material base 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 and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0082] 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.

[0083] 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 disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0084] As an example, the negative electrode active material may adopt the negative electrode active material for cylindrical battery cells 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, lithium titanate, etc. The silicon-based material may 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 may 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 may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0085] 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.

[0086] In some embodiments, the separator is a separator membrane, which can be any known porous separator membrane with good chemical stability and mechanical stability.

[0087] As an example, the material of the separator may include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or may be attached to the surface of the positive and negative electrodes.

[0088] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0089] In some embodiments, the cylindrical battery cell further comprises an electrolyte, which plays a role of conducting ions between the positive and negative electrodes. The electrolyte may be liquid, gel or solid. Among them, the liquid electrolyte comprises an electrolyte salt and a solvent.

[0090] 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 dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0091] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl 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.

[0092] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0093] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0094] 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, and the like.

[0095] 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.

[0096] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0097] 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.

[0098] In some embodiments, the electrode assembly is a laminate structure.

[0099] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0100] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet is folded to form a plurality of stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0101] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded sections.

[0102] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0103] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0104] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0105] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0106] In some embodiments, the 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 (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0107] The battery referred to in the embodiments of the present application refers to a single physical module including one or more cylindrical battery cells to provide higher voltage and capacity.

[0108] In some embodiments, the battery may be a battery module. When there are multiple cylindrical battery cells, the multiple cylindrical battery cells are arranged and fixed to form a battery module.

[0109] In some embodiments, the battery may be a battery pack, which includes a case and cylindrical battery cells, wherein the cylindrical battery cells or battery modules are accommodated in the case.

[0110] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0111] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0112] The development of battery technology must consider many design factors at the same time, such as battery life, energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, the reliability of the battery must also be considered. However, the reliability of current batteries is poor.

[0113] In some embodiments, in order to improve the reliability of the cylindrical battery cell, a pressure relief mechanism may be generally provided on the outer shell of the cylindrical battery cell, and when the cylindrical battery cell thermally runs away, the pressure inside the cylindrical battery cell may be released through the pressure relief mechanism.

[0114] The pressure relief mechanism refers to an element or component that is activated to release the internal pressure of a cylindrical battery cell when the internal pressure reaches a predetermined threshold. The threshold design varies according to different design requirements. The threshold may depend on one or more materials of the positive electrode plate, negative electrode plate, electrolyte and separator in the cylindrical battery cell.

[0115] The "actuation" mentioned in this application refers to the action of the pressure relief mechanism or its activation to a certain state, so that the internal pressure of the cylindrical battery cell can 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 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.

[0116] 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 gases produced by the reaction, flames, etc.

[0117] The cylindrical battery cell includes an electrode terminal, which is disposed in the housing and is used to electrically connect to the electrode assembly so as to output or input the electric energy of the cylindrical battery cell through the electrode terminal. However, it has been found through research that before the internal pressure of the cylindrical battery cell reaches a predetermined threshold (the pressure relief mechanism has not yet been actuated), the electrode terminal may be separated from the housing under the action of the internal pressure, resulting in poor reliability of the battery.

[0118] 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 and an electrode terminal. The shell has a first wall portion, and the first wall portion is provided with a terminal hole. The electrode terminal includes a main body and a first limiting portion, the main body is inserted into the terminal hole, and the first limiting portion is connected to the main body. 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 inside of the shell, and the first limiting portion is configured to limit the main body from escaping from the terminal hole in a direction away from the inside of the shell. Among them, along the thickness direction of the first wall portion, the projection of the outer peripheral surface of the first limiting portion on the first wall portion is arranged around the terminal hole. Along the radial direction of the terminal hole, the minimum distance between the outer peripheral surface and the hole wall of the terminal hole is A, and the radius of the shell is R, which satisfies: 0.06≤A / R≤0.24.

[0119] The first limiting portion can prevent the main body from detaching from the terminal hole in a direction away from the inside of the shell, reducing the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the cylindrical battery cell. When A / R≥0.06, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is large, the area relative to the first limiting portion and the first wall is large, and the limiting effect of the first limiting portion is good, which further reduces the risk of the electrode terminal detaching from the first wall under the action of the internal air pressure of the cylindrical battery cell, and improves the reliability of the cylindrical battery cell. When A / R≤0.24, the minimum distance between the outer circumference of the first limiting portion and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal and reducing the cost of the cylindrical battery cell, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell, reducing the weight of the cylindrical battery cell, and improving the energy density of the cylindrical battery cell. Therefore, when 0.06≤A / R≤0.24, the reliability and cost of the cylindrical battery cell can be taken into account. In addition, the larger the radius of the outer shell, the larger the area of ​​the first wall portion, the easier it is for the first wall portion to deform under the action of the internal air pressure, and the easier it is for the electrode terminal to detach from the first wall portion. Therefore, when the radius of the outer shell increases or decreases, the minimum distance between the outer peripheral surface and the hole wall of the terminal hole can be increased or decreased accordingly to reduce the risk of the electrode terminal detaching from the first wall portion under the action of the internal air pressure of the battery cell, thereby improving the reliability of the battery cell.

[0120] The cylindrical battery cells described in the embodiments of the present application are suitable for batteries and electrical equipment using the cylindrical battery cells.

[0121] Electrical equipment can be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys and electric tools, etc. Vehicles can be fuel vehicles, gas vehicles or new energy vehicles, and new energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles, etc.; spacecraft include aircraft, rockets, space shuttles and spacecraft, etc.; electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc.

[0122] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0123] Please refer to Figure 1 , Figure 1The schematic diagram of the structure of the vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 is provided with a battery 100 inside, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000, for example, the battery 100 can be used as an operating power source of the vehicle 1000.

[0124] The vehicle 1000 may further include a controller 200 and a motor 300 , wherein the controller 200 is used to control the battery 100 to supply power to the motor 300 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1000 .

[0125] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0126] Please refer to Figure 2 , Figure 2 An exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a cylindrical battery cell 10 and a casing 20 , wherein the cylindrical battery cell 10 is accommodated in the casing 20 .

[0127] Among them, the box body 20 is a component for accommodating the cylindrical battery cell 10. The box body 20 provides a storage space for the cylindrical battery cell 10. The box body 20 can adopt a variety of structures. In some embodiments, the box body 20 may include a first box body 201 and a second box body 202. The first box body 201 and the second box body 202 cover each other to define a storage space for accommodating the cylindrical battery cell 10. The first box body 201 and the second box body 202 may be in a variety of shapes, such as a rectangular parallelepiped, a cylindrical shape, etc. The first box body 201 may be a hollow structure with one side open, and the second box body 202 may also be a hollow structure with one side open. The open side of the second box body 202 covers the open side of the first box body 201, thereby forming a box body 20 with a storage space. It is also possible that the first box body 201 is a hollow structure with one side open, and the second box body 202 is a plate-like structure. The second box body 202 covers the open side of the first box body 201, thereby forming a box body 20 with a storage space. The first box body 201 and the second box body 202 can be sealed by a sealing element, and the sealing element can be a sealing ring, a sealant, etc.

[0128] In the battery 100, there may be one or more cylindrical battery cells 10. If there are more than one cylindrical battery cells 10, the multiple cylindrical battery cells 10 may be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple cylindrical battery cells 10 are both connected in series and in parallel. Multiple cylindrical battery cells 10 may be connected in series, in parallel, or in mixed connection to form a battery module, and the multiple battery modules may be connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 20. Alternatively, all cylindrical battery cells 10 may be directly connected in series, in parallel, or in mixed connection, and then the whole formed by all cylindrical battery cells 10 may be accommodated in the box 20.

[0129] Please refer to Figure 3 , Figure 4 and Figure 5 , Figure 3 An exploded view of a cylindrical battery cell 10 provided in some embodiments of the present application. Figure 4 for Figure 3 A cross-sectional view of a cylindrical battery cell 10 is shown. Figure 5 for Figure 4 The upper end of the cylindrical battery cell 10 is shown in an enlarged view. The embodiment of the present application provides a cylindrical battery cell 10, which includes a shell 1 and an electrode terminal 3. The shell 1 has a first wall portion 16, and the first wall portion 16 is provided with a terminal hole. The electrode terminal 3 includes a main body 31 and a first limit portion 32, the main body 31 is penetrated through the terminal hole, and the first limit portion 32 is connected to the main body 31. Along the thickness direction of the first wall portion 16, the first limit portion 32 is located on the side of the first wall portion 16 facing the inside of the shell 1, and the first limit portion 32 is configured to limit the main body 31 from escaping from the terminal hole in a direction away from the inside of the shell 1. Among them, along the thickness direction of the first wall portion 16, the outer peripheral surface of the first limit portion 32 is projected on the first wall portion 16 around the terminal hole. Along the radial direction of the terminal hole, the minimum distance between the outer peripheral surface and the hole wall of the terminal hole is A, and the radius of the shell 1 is R, which satisfies: 0.06≤A / R≤0.24.

[0130] The cylindrical battery cell 10 refers to the smallest unit constituting the battery 100 .

[0131] The housing 1 includes an end cap 12 and a shell 11. The shell 11 has a receiving space with one end open, and the receiving space is used to receive the electrode assembly 2. The end cap 12 is connected to the shell 11 and closes the opening.

[0132] The end cap 12 refers to a component that covers the opening of the shell 11 to isolate the internal environment of the cylindrical battery cell 10 from the external environment. Without limitation, the shape of the end cap 12 can be adapted to the shape of the shell 11 to match the shell 11. Optionally, the end cap 12 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 12 is not easily deformed when squeezed and collided, so that the cylindrical battery cell 10 can have a higher structural strength and the safety performance can also be improved. The material of the end cap 12 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose special restrictions on this. The cylindrical battery cell 10 also includes an insulating member, which is arranged on the inner side of the end cap 12. The insulating member can be used to isolate the electrical connection components in the shell 11 from the end cap 12 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc. Optionally, the end cap 12 is further provided with an electrode terminal 3, which is used to be electrically connected to the tab 21 of the electrode assembly 2 to input or output the electric energy of the cylindrical battery cell 10. The electrode terminal 3 and the tab 21 can be directly connected, for example, the electrode terminal 3 and the tab 21 are directly welded. The electrode terminal 3 and the tab 21 can also be indirectly connected, for example, the electrode terminal 3 and the tab 21 are indirectly connected through the current collecting member 4.

[0133] The shell 11 is a component used to cooperate with the end cap 12 to form the internal environment of the cylindrical battery cell 10, wherein the formed internal environment can be used to accommodate the electrode assembly 2, the electrolyte and other components. The shell 11 and the end cap 12 can be independent components, and an opening can be set on the shell 11, and the internal environment of the cylindrical battery cell 10 is formed by covering the opening with the end cap 12 at the opening. Without limitation, the end cap 12 and the shell 11 can also be integrated. Specifically, the end cap 12 and the shell 11 can form a common joint surface before other components are put into the shell, and when the interior of the shell 11 needs to be encapsulated, the end cap 12 covers the shell 11. The shell 11 of the cylindrical battery cell 10 is cylindrical. The material of the shell 11 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose special restrictions on this.

[0134] The electrode assembly 2 is a component in the cylindrical battery cell 10 where electrochemical reactions occur. One or more electrode assemblies 2 may be included in the housing 1. The electrode assembly 2 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body 22 of the electrode assembly 2, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 21. The positive tab 21 and the negative tab 21 may be located together at one end of the main body 22 or at both ends of the main body 22, respectively. During the charge and discharge process of the battery 100, the positive active material and the negative active material react with the electrolyte.

[0135] As an example, in Figure 3 and Figure 4 In the illustrated embodiment, the housing 11 is formed with an opening at only one end, and there is one end cover 12, which closes the opening of the housing 11, and an electrode terminal 3 is provided on the wall portion of the housing 11 opposite to the end cover 12. Both opposite ends of the electrode assembly 2 are formed with tabs 21, the tab 21 at one end of the electrode assembly 2 is a positive tab, and the tab 21 at the other end is a negative tab, the electrode terminal 3 is electrically connected to the positive tab through a current collecting member 4, and the end cover 12 is electrically connected to the negative tab through another current collecting member 4.

[0136] The first wall portion 16 may be the end cover 12 of the housing 1, or may be a wall of the shell 11 of the housing 1. Figure 3 and Figure 4 In the embodiment, the first wall portion 16 is a wall portion of the housing 11 that is arranged opposite to the end cover 12 .

[0137] The first wall portion 16 is provided with a terminal hole, and the terminal hole penetrates the first wall portion 16 along the thickness direction of the first wall portion 16. In other words, the terminal hole is a through hole provided in the first wall portion 16. Figure 5 , the thickness direction of the first wall portion 16 may be the X1 direction shown in the figure.

[0138] The electrode terminal 3 is installed on the first wall portion 16, and the setting position of the electrode terminal 3 can be used to determine which wall portion of the housing 1 is the first wall portion 16. For example, when the electrode terminal 3 is set on the end cover 12, the end cover 12 is the first wall portion 16. When the electrode terminal 3 is set on the bottom wall 15 of the housing 11, the bottom wall 15 is the first wall portion 16.

[0139] The main body 31 is the main body 22 structure of the electrode terminal 3, and the main body 31 is inserted into the terminal hole. Optionally, the main body 31 is a columnar structure. The first limiter 32 is connected to the end of the main body 31 facing the inside of the housing 1, and along the thickness direction of the first wall 16, the first limiter 32 is closer to the electrode assembly 2 than the first wall 16. The first limiter 32 is used to abut against the first wall 16 to limit the main body 31 from leaving the terminal hole in a direction away from the inside of the housing 1.

[0140] Along the thickness direction of the first wall portion 16, the projection of the first limiting portion 32 on the first wall portion 16 is located outside the terminal hole, so that the projection of the outer circumferential surface of the first limiting portion 32 on the first wall portion 16 surrounds the terminal hole. The first limiting portion 32 may be disc-shaped, the central axis of the first limiting portion 32 substantially coincides with the central axis of the terminal hole, and the diameter of the first limiting portion 32 is greater than the diameter of the terminal hole.

[0141] Please refer to Figure 5, the radial direction of the terminal hole is the Z1 direction shown in the figure.

[0142] A represents the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole along the radial direction of the terminal hole. R represents the radius of the housing 1. When taking a value, half of the outer diameter of the housing 11 can be taken as the radius of the housing 1.

[0143] A / R represents the ratio of the minimum distance between the outer peripheral surface of the first limiting portion 32 and the hole wall surface of the terminal hole along the radial direction of the terminal hole to the radius of the housing 1 .

[0144] The ratio of the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole along the radial direction of the terminal hole to the radius of the housing 1 can be: A / R=0.06, 0.08, 0.1, 0.12, 0.14, 0.16, 0.18, 0.2, 0.22, 0.24, etc.

[0145] The first limiting portion 32 can prevent the main body 31 from detaching from the terminal hole in a direction away from the inside of the housing 1, thereby reducing the risk of the electrode terminal 3 detaching from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10. When A / R≥0.06, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is large, the area of ​​the first limiting portion 32 relative to the first wall 16 is large, and the limiting effect of the first limiting portion 32 is good, which further reduces the risk of the electrode terminal 3 detaching from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10, thereby improving the reliability of the cylindrical battery cell 10. When A / R≤0.24, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.06≤A / R≤0.24, the reliability and cost of the cylindrical battery cell 10 can be taken into account. In addition, the larger the radius of the outer shell 1, the larger the area of ​​the first wall portion 16, the easier it is for the first wall portion 16 to deform under the action of the internal air pressure, and the easier it is for the electrode terminal 3 to detach from the first wall portion 16. Therefore, when the radius of the outer shell 1 increases or decreases, the minimum distance between the outer peripheral surface and the hole wall surface of the terminal hole can be increased or decreased accordingly, so as to reduce the risk of the electrode terminal 3 detaching from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10, thereby improving the reliability of the cylindrical battery cell 10.

[0146] Optionally, 0.08≤A / R≤0.19.

[0147] The ratio of the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole along the radial direction of the terminal hole to the radius of the housing 1 can be: A / R=0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, etc.

[0148] When A / R≥0.08, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is larger, the area of ​​the first limiting portion 32 relative to the first wall 16 is larger, and the limiting effect of the first limiting portion 32 is better, which can further reduce the risk of the electrode terminal 3 being separated from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10, and improve the reliability of the cylindrical battery cell 10. When A / R≤0.19, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.08≤A / R≤0.19, it is more possible to take into account both the reliability and cost of the cylindrical battery cell 10.

[0149] In some embodiments, 3 mm ≤ A ≤ 11 mm.

[0150] The minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall of the terminal hole along the radial direction of the terminal hole can be: A=3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, etc.

[0151] When A≥3mm, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is larger, the area of ​​the first limiting portion 32 relative to the first wall 16 is larger, and the limiting effect of the first limiting portion 32 is better, which further reduces the risk of the electrode terminal 3 being separated from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10, and improves the reliability of the cylindrical battery cell 10. When A≤11mm, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 3mm≤A≤11mm, the reliability and cost of the cylindrical battery cell 10 can be taken into account.

[0152] Optionally, 3.9mm≤A≤8.65mm.

[0153] The minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall of the terminal hole along the radial direction of the terminal hole can be: A=3.9mm, 4mm, 4.2mm, 4.5mm, 4.8mm, 5mm, 5.2mm, 5.5mm, 5.8mm, 6mm, 6.2mm, 6.5mm, 6.8mm, 7mm, 7.2mm, 7.5mm, 7.8mm, 8mm, 8.2mm, 8.5mm, 8.65mm, etc.

[0154] When A≥3.9mm, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is larger, the area of ​​the first limiting portion 32 relative to the first wall portion 16 is larger, and the limiting effect of the first limiting portion 32 is better, which can further reduce the risk of the electrode terminal 3 being separated from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10, and improve the reliability of the cylindrical battery cell 10. When A≤8.65mm, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 3.9mm≤A≤8.65mm, it is more possible to take into account both the reliability and cost of the cylindrical battery cell 10.

[0155] In some embodiments, 19 mm ≤ R ≤ 40 mm.

[0156] The radius of the housing 1 may be: R=19 mm, 20 mm, 23 mm, 25 mm, 28 mm, 30 mm, 32 mm, 34 mm, 36 mm, 38 mm, 40 mm, etc.

[0157] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, along the thickness direction of the first wall portion 16 , the minimum thickness of the first limiting portion 32 is H, satisfying: 0.4 mm ≤ H ≤ 2 mm.

[0158] H represents the minimum thickness of the first limit portion 32 along the thickness direction of the first wall portion 16. The minimum thickness of the first limit portion 32 along the thickness direction of the first wall portion 16 can be: H=0.4mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, etc.

[0159] When H≥0.4mm, the minimum thickness of the first limit portion 32 is thicker, the strength of the first limit portion 32 is greater, and the risk of the first limit portion 32 breaking is reduced, which reduces the risk of the electrode terminal 3 being separated from the first wall portion 16 under the internal air pressure of the cylindrical battery cell 10, and improves the reliability of the cylindrical battery cell 10. When H≤2mm, the thickness of the first limit portion 32 is not too large, and the thickness of the first limit portion 32 is not too thick, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.4mm≤H≤2mm, the reliability and energy density of the cylindrical battery cell 10 can be taken into account.

[0160] Optionally, 0.8mm≤H≤1.6mm.

[0161] The minimum thickness of the first limiting portion 32 along the thickness direction of the first wall portion 16 can be: H=0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, etc.

[0162] When H≥0.8mm, the minimum thickness of the first limit portion 32 is thicker, the strength of the first limit portion 32 is greater, the risk of the first limit portion 32 breaking is further reduced, and the risk of the electrode terminal 3 being separated from the first wall portion 16 under the internal air pressure of the cylindrical battery cell 10 is further reduced, thereby improving the reliability of the cylindrical battery cell 10. When H≤2mm, the thickness of the first limit portion 32 is not too large, and the thickness of the first limit portion 32 is not too thick, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.4mm≤H≤2mm, it is more possible to take into account both the reliability and energy density of the cylindrical battery cell 10.

[0163] In some embodiments, the electrode terminal 3 is made of aluminum.

[0164] The material of the electrode terminal 3 may be pure aluminum, or various aluminum alloys, such as three-series aluminum alloy, five-series aluminum alloy, etc.

[0165] By selecting aluminum as the material of the electrode terminal 3 , it is convenient to weld the electrode terminal 3 to the positive electrode current collecting member 4 or the positive electrode tab.

[0166] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, the electrode terminal 3 includes a second limiting portion 33 connected to an end of the main body 31 away from the interior of the housing 1. The second limiting portion 33 cooperates with the first limiting portion 32 to clamp the first wall portion 16.

[0167] The first limiting portion 32 and the second limiting portion 33 are respectively connected to the two ends of the main body 31. The first limiting portion 32 can limit the main body 31 from being separated from the terminal hole in a direction facing the inside of the housing 1, and the second limiting portion 33 can limit the main body 31 from being separated from the terminal hole in a direction away from the inside of the housing 1.

[0168] The first limiting portion 32 and the second limiting portion 33 are arranged opposite to each other along the thickness direction of the first wall portion 16 . The first limiting portion 32 and the second limiting portion 33 can cooperate to clamp the first wall portion 16 to limit the main body portion 31 from being separated from the terminal hole.

[0169] By respectively providing a first limiting portion 32 and a second limiting portion 33 at both ends of the main body 31, the first limiting portion 32 and the second limiting portion 33 can cooperate to clamp the first wall portion 16, thereby limiting the main body 31 in the terminal hole. The first limiting portion 32 can limit the main body 31 from escaping from the terminal hole in a direction facing the inside of the housing 1, and the second limiting portion 33 can limit the main body 31 from escaping from the terminal hole in a direction away from the inside of the housing 1. The first limiting portion 32 and the second limiting portion 33 work together to have a good limiting effect on the main body 31.

[0170] In some embodiments, the electrode terminal 3 is provided with a liquid injection hole, and the liquid injection hole is used to inject electrolyte into the housing 1.

[0171] The injection hole is a through hole for injecting electrolyte into the housing 1. The injection hole penetrates the electrode terminal 3 along the thickness direction of the first wall portion 16. After the injection is completed, the injection hole is sealed to reduce the risk of electrolyte leakage in the housing 1.

[0172] By providing the injection hole on the electrode terminal 3 , it is helpful to reduce the area occupied by the injection hole on the first wall portion 16 , and it is helpful to reduce the volume of the cylindrical battery cell 10 .

[0173] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, the housing 1 includes a shell 11 and an end cover 12 , wherein one end of the shell 11 has an opening, and the end cover 12 closes the opening. The shell 11 includes a first wall portion 16 .

[0174] The housing 11 includes a bottom wall 15 and a side wall 14. The side wall 14 is disposed around the bottom wall 15. One end of the side wall 14 is connected to the bottom wall 15. The other end of the side wall 14 is surrounded to form an opening. The end cover 12 is disposed on the opening and is disposed opposite to the bottom wall 15.

[0175] One of the side wall 14 and the bottom wall 15 is the first wall portion 16. For example, the bottom wall 15 can be the first wall portion 16. For another example, the side wall 14 can be the first wall portion 16.

[0176] When the housing 11 includes the first wall portion 16 , the electrode terminal 3 is disposed on the housing 11 , which facilitates the electrical connection between the electrode assembly 2 and the electrode terminal 3 during manufacturing.

[0177] Please refer to Figure 3 , Figure 4 and Figure 5 In some embodiments, the housing 11 includes a bottom wall 15 and a side wall 14 , wherein the side wall 14 is disposed around the bottom wall 15 , one end of the side wall 14 is connected to the bottom wall 15 , and the other end of the side wall 14 is surrounded to form an opening. The bottom wall 15 is a first wall portion 16 .

[0178] The bottom wall 15 is the first wall portion 16 , and the electrode terminal 3 is disposed on the bottom wall 15 . This makes it convenient to install the electrode terminal 3 , helps to accurately install the electrode terminal 3 , and makes the connection between the electrode terminal 3 and the electrode assembly 2 more stable.

[0179] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 , Figure 6 for Figure 4 An enlarged view of the lower end of a cylindrical battery cell 10 is shown. Figure 7 for Figure 6 A schematic structural diagram of the second wall portion 13 is shown. Figure 8 for Figure 7 AA cross-sectional view of the second wall portion 13 shown. The cylindrical battery cell 10 includes an electrode assembly 2, and the electrode assembly 2 is accommodated in the outer shell 1. The outer shell 1 includes a second wall portion 13 and a side wall 14, the second wall portion 13 is arranged at one end of the side wall 14 along the axial direction of the cylindrical battery cell 10, and the side wall 14 is a cylindrical structure and is arranged around the second wall portion 13. A first guide channel 6 is formed between the pole ear 21 of the electrode assembly 2 facing the second wall portion 13 and the side wall 14. Among them, the second wall portion 13 includes a wall body 131 and a supporting portion 132, the wall body 131 is provided with a pressure relief mechanism 5, and the supporting portion 132 is arranged around the outer edge of the wall body 131. Along the axial direction of the cylindrical battery cell 10, the supporting portion 132 protrudes from the wall body 131 in a direction close to the electrode assembly 2, and directly or indirectly abuts against the electrode assembly 2. The abutting portion 132 and the wall body 131 together define a flow guiding space 133 . The abutting portion 132 is provided with a second flow guiding channel 1321 . The second flow guiding channel 1321 connects the flow guiding space 133 and the first flow guiding channel 6 .

[0180] The second wall portion 13 is disposed at one end of the side wall 14 along the axial direction of the cylindrical battery cell 10. Figure 6 and Figure 8 The axial direction of the cylindrical battery cell 10 is the X2 direction shown in the figure. The thickness direction of the first wall portion 16 can be the same as the axial direction of the cylindrical battery cell 10, or can be different from the axial direction of the cylindrical battery cell 10. Figure 6 and Figure 8 In the illustrated embodiment, the thickness direction of the first wall portion 16 is the same as the axial direction of the cylindrical battery cell 10 .

[0181] In the embodiment where the housing 11 is opened at only one end, the end cap 12 may be used as the second wall portion 13, and the side wall 14 may be a part of the housing 11; or the wall portion of the housing 11 opposite to the end cap 12 may be used as the second wall portion 13, and the side wall 14 and the second wall portion 13 may be integrally formed to form the housing 11. In the embodiment where openings are formed at both opposite ends of the housing 11, at least one of the two end caps 12 may be used as the second wall portion 13, and the side wall 14 is the housing 11.

[0182] In the cylindrical battery cell 10, the side wall 14 is cylindrical. The side wall 14 and the second wall portion 13 can be integrally formed, and the side wall 14 and the second wall portion 13 constitute the housing 11, and the end of the side wall 14 away from the second wall portion 13 along the axial direction of the cylindrical battery cell 10 forms an opening of the housing 11; the side wall 14 and the second wall portion 13 can also be separately arranged, and the second wall portion 13 is the end cover 12, and the end of the side wall 14 close to the second wall portion 13 along the axial direction of the cylindrical battery cell 10 forms an opening of the housing 11. In the embodiment where the side wall 14 and the second wall portion 13 are separately arranged, the second wall portion 13 and the side wall 14 can be connected by welding, bonding, crimping, etc.

[0183] The electrode assembly 2 may include a main body 22 and a tab 21, and the main body 22 is provided with a tab 21 at least at one end along the axial direction of the cylindrical battery cell 10. The first guide channel 6 is a gap formed between the outer peripheral surface of the tab 21 of the electrode assembly 2 facing the second wall portion 13 and the inner peripheral surface 141 of the side wall 14. Among them, the inner peripheral surface 141 of the side wall 14 is the surface of the side wall 14 facing the electrode assembly 2, and the inner peripheral surface 141 may extend along the circumference of the opening of the housing 1 for a whole circumference. It can be understood that the side wall 14 is cylindrical, and the inner peripheral surface 141 of the side wall 14 is also cylindrical.

[0184] The wall body 131 and the abutment portion 132 may be integrally formed, or may be separately provided and connected. The pressure relief mechanism 5 may be a pressure relief component separately provided from the wall body 131, and the pressure relief component is installed on the wall body 131. The pressure relief component may be a burst-proof disk, a pressure relief valve, etc. The pressure relief mechanism 5 may also be a structure integrally formed with the wall body 131, for example, the pressure relief mechanism 5 is a weak portion formed on the wall body 131. The weak portion may be formed by providing a groove on the wall body 131, or by heat treating a part of the wall body 131 so that the strength of the local area is weakened to form a corresponding weak portion.

[0185] The abutting portion 132 may be an annular structure surrounding the outer edge of the wall body 131, and the annular structure may be a circular ring structure, a rectangular ring structure, etc. After the abutting portion 132 directly or indirectly abuts against the electrode assembly 2, the abutting portion 132 and the electrode assembly 2 may be electrically connected or insulated. If the abutting portion 132 directly abuts against the electrode assembly 2, the abutting portion 132 is in direct contact with the electrode assembly 2, for example, the abutting portion 132 directly abuts against the pole ear 21 at the end of the electrode assembly 2 to achieve electrical connection between the second wall portion 13 and the electrode assembly 2; if the abutting portion 132 indirectly abuts against the electrode assembly 2, an intermediate piece is provided between the abutting portion 132 and the electrode assembly 2, and the intermediate piece may be an insulating piece or a conductive piece. Taking the intermediate piece as the current collecting component 4 as an example, the abutting portion 132 may be indirectly abutted against the pole ear 21 at the end of the electrode assembly 2 through the current collecting component 4 to achieve electrical connection between the second wall portion 13 and the electrode assembly 2.

[0186] The flow guide space 133 defined by the wall body 131 and the abutment portion 132 corresponds to the pressure relief mechanism 5. After the pressure relief mechanism 5 is actuated, the discharge in the flow guide space 133 can be discharged to the outside of the cylindrical battery cell 10 through the pressure relief mechanism 5. Along the axial direction of the cylindrical battery cell 10, the flow guide space 133 is formed with an opening at one end of the abutment portion 132 close to the electrode assembly 2. After the abutment portion 132 directly or indirectly abuts against the electrode assembly 2, the opening is covered. It can be understood that if the abutment portion 132 directly abuts against the electrode assembly 2, the opening of the flow guide space 133 is covered by the electrode assembly 2; if the abutment portion 132 indirectly abuts against the electrode assembly 2 through an intermediate piece, the opening of the flow guide space 133 is covered by the intermediate piece.

[0187] The number of the second flow guiding channels 1321 on the abutting portion 132 may be one or more. If there are more than one second flow guiding channels 1321 , the plurality of flow guiding channels may be evenly distributed along the circumference of the cylindrical battery cell 10 , or may be unevenly distributed along the circumference of the cylindrical battery cell 10 .

[0188] The second guide channel 1321 can be a through hole that penetrates the abutment portion 132 along the radial direction of the cylindrical battery cell 10, or a notch groove that penetrates the abutment portion 132 along the radial direction of the cylindrical battery cell 10 and extends along the axial direction of the cylindrical battery cell 10 to one end of the abutment portion 132 close to the electrode assembly 2.

[0189] Please refer to Figure 6 and Figure 8 , the radial direction of the cylindrical battery cell 10 may be the Z2 direction shown in the figure. The radial direction of the terminal hole may be the same as the radial direction of the cylindrical battery cell 10, or the radial direction of the terminal hole may be different from the radial direction of the cylindrical battery cell 10. Figure 6 and Figure 8 In the illustrated embodiment, the radial direction of the terminal hole is the same as the radial direction of the cylindrical battery cell 10 .

[0190] The abutting portion 132 of the second wall portion 13 abuts against the electrode assembly 2 directly or indirectly, and the abutting portion 132 can limit the electrode assembly 2, reducing the risk of the electrode assembly 2 moving along the axial direction of the cylindrical battery cell 10 in the housing 1. Since the abutting portion 132 is provided with a second guide channel 1321, the second guide channel 1321 connects the guide space 133 with the first guide channel 6. When the cylindrical battery cell 10 is in thermal runaway, the emission generated by the electrode assembly 2 flows into the first guide channel 6, and the emission can quickly flow into the guide space 133 through the second guide channel 1321 on the abutting portion 132, so that the gas pressure in the guide space 133 is quickly increased to quickly reach the bursting pressure of the pressure relief mechanism 5, shortening the time from the thermal runaway of the cylindrical battery cell 10 to the start of pressure relief of the cylindrical battery cell 10 through the pressure relief mechanism 5, so that the pressure relief mechanism 5 can be actuated in time, reducing the risk of explosion and fire of the cylindrical battery cell 10, and effectively improving the reliability of the cylindrical battery cell 10. In addition, precisely because the pressure relief mechanism 5 can be activated in time, the emissions generated by the electrode assembly 2 are not easily retained in the cylindrical battery cell 10, and the internal air pressure of the cylindrical battery cell 10 is not too high, thereby reducing the risk of the electrode terminal 3 detaching from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10, thereby improving the reliability of the cylindrical battery cell 10.

[0191] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the abutting portion 132 is provided with a plurality of second guide channels 1321 , and the plurality of second guide channels 1321 are arranged at intervals along the circumference of the cylindrical battery cell 10 .

[0192] The number of the second guide channels 1321 on the abutting portion 132 may be two, three, four, five, six or more.

[0193] As an example, the plurality of second flow guiding channels 1321 on the abutting portion 132 are evenly distributed along the circumference of the cylindrical battery cell 10, that is, the angles between each two adjacent second flow guiding channels 1321 along the circumference of the cylindrical battery cell 10 are equal. For example, if there are four second flow guiding channels 1321 on the abutting portion 132, each two adjacent second flow guiding channels 1321 along the circumference of the cylindrical battery cell 10 are 90° apart.

[0194] By providing a plurality of second guide channels 1321 spaced apart along the circumference of the cylindrical battery cell 10, the emissions in the first guide channel 6 can enter the guide space 133 from the plurality of second guide channels 1321 at different positions, thereby increasing the rate at which the emissions in the first guide channel 6 enter the guide space 133, and further shortening the time from thermal runaway of the cylindrical battery cell 10 to the start of pressure relief of the cylindrical battery cell 10 through the pressure relief mechanism 5.

[0195] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 In some embodiments, along the axial direction of the cylindrical battery cell 10, the abutment portion 132 has an abutment surface 1322, and the abutment surface 1322 is the surface of the abutment portion 132 closest to the electrode assembly 2, and the second guide channel 1321 is a notch groove that penetrates the abutment portion 132 along the radial direction of the cylindrical battery cell 10 and extends along the axial direction of the cylindrical battery cell 10 to the abutment surface 1322.

[0196] The abutting surface 1322 is not only the surface of the abutting portion 132 closest to the electrode assembly 2, but also the surface of the entire second wall portion 13 closest to the electrode assembly 2. The notch groove penetrates the abutting portion 132 in the radial direction of the cylindrical battery cell 10, so that the second guide channel 1321 connects the guide space 133 and the first guide channel 6. The notch groove extends along the axial direction of the cylindrical battery cell 10 to the abutting surface 1322, and the notch groove can be formed by being recessed from the abutting surface 1322 in a direction away from the electrode assembly 2, and the notch groove forms a notch on the abutting surface 1322.

[0197] In the embodiment where the abutting portion 132 directly abuts against the electrode assembly 2, the abutting surface 1322 may be in direct contact with the pole ear 21 at the end of the electrode assembly 2, and the pole ear 21 covers the notch formed by the notch groove on the abutting surface 1322; in the embodiment where the abutting portion 132 and the electrode assembly 2 indirectly abut against the electrode assembly 2 via an intermediate piece, the abutting surface 1322 may be in direct contact with the intermediate piece, and the intermediate piece covers the notch formed by the notch groove on the abutting surface 1322.

[0198] The second guide channel 1321 is a notch groove that penetrates the abutment portion 132 along the radial direction of the cylindrical battery cell 10 and extends to the abutment surface 1322 along the axial direction of the cylindrical battery cell 10. On the one hand, it can reduce the difficulty of forming the second guide channel 1321. On the other hand, it is beneficial to increase the axial size of the second guide channel 1321 along the cylindrical battery cell 10, and increase the rate at which the discharge in the first guide channel 6 enters the guide space 133 through the second guide channel 1321.

[0199] Please refer to Figure 4 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the abutting portion 132 includes a plurality of protrusions 1323 , which directly or indirectly abut against the electrode assembly 2 , and a second guide channel 1321 is formed between two adjacent protrusions 1323 along the circumference of the cylindrical battery cell 10 .

[0200] The number of protrusions 1323 in the abutting portion 132 may be two, three, four, five or more. The number of the second guide channels 1321 and the protrusions 1323 is equal, and the second guide channels 1321 and the protrusions 1323 are alternately arranged along the circumference of the cylindrical battery cell 10. As an example, the multiple protrusions 1323 in the abutting portion 132 are evenly distributed along the circumference of the cylindrical battery cell 10, that is, the angles between each two adjacent protrusions 1323 along the circumference of the cylindrical battery cell 10 are equal. Taking the example of four protrusions 1323 in the abutting portion 132, each two adjacent protrusions 1323 along the circumference of the cylindrical battery cell 10 are 90° apart.

[0201] The protrusion 1323 is located inside the side wall 14 . The protrusion 1323 may be in contact with the inner surface of the side wall 14 , or there may be a gap between them.

[0202] By forming a second guide channel 1321 between two adjacent protrusions 1323, the discharge in the first guide channel 6 can enter the guide space 133 from multiple second guide channels 1321 at different positions, thereby increasing the rate at which the discharge in the first guide channel 6 enters the guide space 133. In addition, the second guide channel 1321 of this structure is a notch groove formed on the abutment portion 132, which can reduce the difficulty of forming the second guide channel 1321 and is conducive to increasing the size of the second guide channel 1321 along the axial direction of the cylindrical battery cell 10.

[0203] Please refer to Fig. 9 , Fig.10 , Fig.11 and Fig.12 , Fig. 9 A partially enlarged view of a cylindrical battery cell 10 provided in some other embodiments of the present application. Fig.10 for Fig. 9 A partial enlarged view of point C in the middle. Fig.11 for Fig. 9 A schematic structural diagram of the second wall portion 13 is shown. Fig.12 for Fig.11 The DD cross-sectional view of the second wall portion 13 is shown. In some embodiments, a flow guiding gap 7 is formed between the side wall 14 and the protruding portion 1323 , and the flow guiding gap 7 communicates with two adjacent second flow guiding channels 1321 .

[0204] The flow guide gap 7 is formed between the inner circumferential surface 141 of the side wall 14 and the surface of the protrusion 1323 facing the inner circumferential surface 141 of the side wall 14. The protrusion 1323 may not contact the inner circumferential surface 141 of the side wall 14 to form the flow guide gap 7 between the protrusion 1323 and the side wall 14, or a part of the protrusion 1323 may contact the inner circumferential surface 141 of the side wall 14, and the other part may not contact the inner circumferential surface 141 of the side wall 14 to form the flow guide gap 7 between the protrusion 1323 and the side wall 14.

[0205] The guide gap 7 between the side wall 14 and the protrusion 1323 can connect two adjacent second guide channels 1321. When the emissions in the first guide channel 6 flow toward one of the second guide channels 1321, the emissions can flow toward another adjacent second guide channel 1321 through the guide gap 7, so that the emissions in the first guide channel 6 can enter the guide space 133 more quickly.

[0206] For example, when the cylindrical battery cell 10 is in thermal runaway, if the thermal runaway area of ​​the electrode assembly 2 is close to a second guide channel 1321, the emissions generated by the thermal runaway of the electrode assembly 2 will flow concentratedly to the second guide channel 1321. When the second guide channel 1321 is unable to guide the emissions into the guide space 133 in time, the emissions that have not entered the guide space 133 in time can flow to another adjacent second guide channel 1321 through the guide gap 7, and then quickly enter the guide space 133.

[0207] Please refer to Fig. 9 , Fig.10 , Fig.11 and Fig.12 In some embodiments, the abutting portion 132 further includes a body portion 1324, which is disposed around the outer edge of the wall body 131 and protrudes from the wall body 131 in a direction close to the electrode assembly 2. Along the axial direction of the cylindrical battery cell 10, the body portion 1324 has a first surface 13241 facing the electrode assembly 2, and the protrusion 1323 protrudes from the first surface 13241.

[0208] The body portion 1324 may be an annular structure surrounding the outer edge of the wall body 131. The first surface 13241 may be the surface of the body portion 1324 closest to the electrode assembly 2 along the axial direction of the cylindrical battery cell 10. The protrusion 1323 is disposed on the first surface 13241, so that the protrusion 1323 extends from the first surface 13241 in a direction close to the electrode assembly 2. The second guide channel 1321 between two adjacent protrusions 1323 is a notch groove, and the groove bottom surface of the notch groove is located on the first surface 13241.

[0209] The main body 1324 and the wall body 131 can be formed as one piece; the main body 1324 and the wall body 131 can also be set separately and connected to each other, and the connection method between the two can be welding, bonding, etc.; the protrusion 1323 and the main body 1324 can be formed as one piece; the protrusion 1323 and the main body 1324 can also be set separately and connected to each other, and the connection method between the two can be welding, bonding, etc.

[0210] In this embodiment, the main body 1324 serves to connect the wall body 131 and the protruding portion 1323 . The main body 1324 is arranged around the wall body 131 and protrudes from the wall body 131 in a direction close to the electrode assembly 2 , which can effectively improve the deformation resistance of the second wall portion 13 .

[0211] In some embodiments, please refer to Fig. 9 , Fig.10 , Fig.11 and Fig.12 Along the axial direction of the cylindrical battery cell 10 , the wall body 131 has a second surface 1311 , which is the surface of the wall body 131 closest to the electrode assembly 2 , and the first surface 13241 is closer to the electrode assembly 2 than the second surface 1311 .

[0212] Along the axial direction of the cylindrical battery cell 10, the wall body 131 has a sixth surface 1313 facing the electrode assembly 2, and the body portion 1324 extends from the sixth surface 1313 toward the electrode assembly 2. The second surface 1311 and the sixth surface 1313 can be the same surface or different surfaces. Fig.12 In the illustrated embodiment, the second surface 1311 and the sixth surface 1313 are different surfaces. Along the axial direction of the cylindrical battery cell 10 , the second surface 1311 is closer to the electrode assembly 2 than the sixth surface 1313 .

[0213] In this embodiment, the first surface 13241 is closer to the electrode assembly 2 than the second surface 1311, which can increase the distance between the second surface 1311 and the electrode assembly 2, reduce the influence of the electrode assembly 2 on the pressure relief mechanism 5 on the wall body 131, and effectively increase the axial size of the guide space 133 along the cylindrical battery cell 10.

[0214] In some embodiments, please refer to Fig.10 , the abutting portion 132 is provided with a first groove 1325. Along the axial direction of the cylindrical battery cell 10, the main body portion 1324 has a third surface 13242 arranged opposite to the first surface 13241, the first surface 13241 is closer to the electrode assembly 2 than the third surface 13242, and the first groove 1325 is recessed from the third surface 13242 toward the direction close to the electrode assembly 2, so as to form a protrusion 1323 protruding from the first surface 13241 on the side of the main body portion 1324 facing the electrode assembly 2.

[0215] The first groove 1325 corresponds to the protrusion 1323 one by one. The first groove 1325 can be formed on the abutting portion 132 by stamping. By stamping the first groove 1325 on the third surface 13242, the protrusion 1323 protruding from the first surface 13241 of the main body 1324 can be formed correspondingly, so that the protrusion 1323 and the main body 1324 are integrally formed. The first groove 1325 can be a primary groove, and the first groove 1325 can be formed by only one stamping during the processing; the first groove 1325 can also be a multi-stage groove, and the multi-stage groove can be formed step by step by multiple stampings during the processing.

[0216] By providing the first groove 1325 on the abutting portion 132 to form the protruding portion 1323 accordingly, the difficulty of forming the protruding portion 1323 can be effectively reduced, and the weight of the second wall portion 13 can be effectively reduced.

[0217] In some embodiments, please refer to Fig.10 The first groove 1325 is a multi-level groove. Along the axial direction of the cylindrical battery cell 10 , the first groove close to the electrode assembly 2 of the two adjacent grooves is arranged at the groove bottom surface of the first groove away from the electrode assembly 2 .

[0218] It is understood that the first groove 1325 is a stepped groove. The first groove 1325 can be a two-level groove, a three-level groove, a four-level groove, a five-level groove, etc. As an example, in Fig.10 In the illustrated embodiment, the first groove 1325 is a two-stage groove.

[0219] By configuring the first groove 1325 as a multi-stage groove, the second wall portion 13 is subjected to a lower forming force when forming each stage of the groove, thereby reducing the risk of the second wall portion 13 being damaged due to excessive forming force when forming the first groove 1325 .

[0220] In some embodiments, the protrusion 1323 includes a first portion 13233 and a second portion 13234, and the multi-stage groove includes a first-stage groove 13251 and a second-stage groove 13252. The first-stage groove 13251 is recessed from the third surface 13242 in a direction close to the electrode assembly 2 to form a first portion 13233 protruding from the first surface 13241 on the side of the body portion 1324 facing the electrode assembly 2, and along the axial direction of the cylindrical battery cell 10, the first portion 13233 has a fourth surface 13233a facing the electrode assembly 2. The second-stage groove 13252 is recessed from the bottom surface of the first-stage groove 13251 in a direction close to the electrode assembly 2 to form a second portion 13234 protruding from the fourth surface 13233a on the side of the first portion 13233 facing the electrode assembly 2.

[0221] It should be noted that the protrusion 1323 may include only the first part 13233 and the second part 13234, or may include other parts except the first part 13233 and the second part 13234. If the protrusion 1323 includes only the first part 13233 and the second part 13234, along the axial direction of the cylindrical battery cell 10, the sum of the heights of the first part 13233 and the second part 13234 is equal to the height of the protrusion 1323. The multi-stage groove may include only the first-stage groove 13251 and the second-stage groove 13252, or may include other-stage grooves except the first-stage groove 13251 and the second-stage groove 13252. Taking the multi-stage groove including only the first-stage groove 13251 and the second-stage groove 13252 as an example, both the first-stage groove 13251 and the second-stage groove 13252 can be stamped. During molding, a first-level groove 13251 can be punched out on the third surface 13242 to form a first part 13233 protruding from the first surface 13241; and then a second-level groove 13252 can be punched out on the bottom surface of the first-level groove 13251 to form a second part 13234 of the fourth surface 13233a protruding from the first part 13233, and finally the first groove 1325 and the protrusion 1323 are formed.

[0222] The first portion 13233 and the second portion 13234 are both located inside the side wall 14. The first portion 13233 may contact the inner surface of the side wall 14 or have a gap therebetween. The second portion 13234 may contact the inner surface of the side wall 14 or have a gap therebetween.

[0223] In this embodiment, by setting a first-level groove 13251 on the main body 1324, the first part 13233 of the protrusion 1323 can be formed accordingly, and by setting a second-level groove 13252 on the first part 13233, the second part 13234 of the protrusion 1323 can be formed accordingly, which can reduce the difficulty of molding the protrusion 1323.

[0224] In some embodiments, please refer to Fig.10 Along the radial direction of the cylindrical battery cell 10, the first part 13233 has a first side surface 13233b facing the inner circumferential surface 141 of the side wall 14, and the second part 13234 has a second side surface 13234a facing the inner circumferential surface 141 of the side wall 14. The first side surface 13233b is closer to the inner circumferential surface 141 of the side wall 14 than the second side surface 13234a. A guide gap 7 is formed between the second side surface 13234a and the inner circumferential surface 141 of the side wall 14, and the guide gap 7 connects two adjacent second guide channels 1321.

[0225] A flow guide gap 7 is formed between the second side surface 13234a and the inner peripheral surface 141 of the side wall 14, that is, the second side surface 13234a does not contact the inner peripheral surface 141 of the side wall 14. Of course, a flow guide gap 7 may also be formed between the first side surface 13233b and the inner peripheral surface 141 of the side wall 14, or they may directly contact each other.

[0226] As an example, the first side surface 13233b and the second side surface 13234a are arc surfaces whose central axes extend along the axial direction of the cylindrical battery cell 10 , and the central axes of the first side surface 13233b and the second side surface 13234a coincide with the central axis of the inner circumferential surface 141 of the side wall 14 .

[0227] In this embodiment, the guide gap 7 between the second side surface 13234a and the inner circumferential surface 141 of the side wall 14 can connect two adjacent second guide channels 1321. When the emissions in the first guide channel 6 flow toward one of the second guide channels 1321, the emissions can flow toward another adjacent second guide channel 1321 through the guide gap 7, so that the emissions in the first guide channel 6 can enter the guide space 133 more quickly.

[0228] In some embodiments, the cylindrical battery cell 10 may further include a current collecting member 4, which is disposed between the second wall portion 13 and the electrode assembly 2 along the axial direction of the cylindrical battery cell 10, the current collecting member 4 electrically connects the electrode assembly 2 and the second wall portion 13, the abutting portion 132 directly abuts against the current collecting member 4, and the current collecting member 4 directly abuts against the electrode assembly 2.

[0229] The current collecting member 4 is a conductive member for realizing electrical connection between the electrode assembly 2 and the second wall portion 13. The current collecting member 4 is located in the housing 1 and between the second wall portion 13 and the electrode assembly 2. The current collecting member 4 can be welded to the electrode lug 21 at the end of the electrode assembly 2, and the current collecting member 4 can also be welded to the abutment portion 132.

[0230] In this embodiment, the abutting portion 132 indirectly abuts against the electrode assembly 2 through the current collecting member 4 , and the electrical connection between the electrode assembly 2 and the second wall portion 13 can be achieved through the current collecting member 4 , thereby reducing the difficulty of electrical connection between the electrode assembly 2 and the second wall portion 13 .

[0231] In some embodiments, the electrode assembly 2 is provided with a first central hole 23 , and the current collecting member 4 is provided with a second central hole 41 , and the second central hole 41 communicates with the first central hole 23 and the flow guiding space 133 .

[0232] As an example, the electrode assembly 2 is a winding structure, and the first center hole 23 is located at the winding center of the winding structure. The first center hole 23 and the second center hole 41 are both cylindrical holes, the first center hole 23 and the second center hole 41 are coaxially arranged, and the aperture of the first center hole 23 is larger than the aperture of the second center hole 41.

[0233] When the cylindrical battery cell 10 thermally runs away, the emissions generated by the electrode assembly 2 can enter the guide space 133 through the first center hole 23 and the second center hole 41 in sequence, further shortening the time from the thermal runaway of the cylindrical battery cell 10 to the cylindrical battery cell 10 starting to release pressure through the pressure relief mechanism 5, so that the pressure relief mechanism 5 can be actuated more timely.

[0234] In some embodiments, the housing 1 includes a shell 11 and an end cap 12. The shell 11 has an opening formed at at least one end along the axial direction of the cylindrical battery cell 10, and the end cap 12 closes the opening. The end cap 12 is a second wall portion 13, and the shell 11 includes a side wall 14.

[0235] The shell 11 may have an opening at only one end along the axial direction of the cylindrical battery cell 10, and one end cap 12 is provided accordingly. The shell 11 may have openings at both ends along the axial direction of the cylindrical battery cell 10, and two end caps 12 are provided accordingly, and the two end caps 12 respectively close the two opposite openings of the shell 11. It can be understood that the second wall portion 13 and the side wall 14 are provided separately.

[0236] In this embodiment, the end cover 12 is the second wall portion 13, so that the end cover 12 is provided with a pressure relief mechanism 5, which reduces the difficulty of molding or installing the pressure relief mechanism 5, and the second guide channel 1321 is provided on the end cover 12, which reduces the difficulty of molding the second guide channel 1321.

[0237] The embodiment of the present application further provides a battery 100 , which includes the cylindrical battery cell 10 described above.

[0238] The embodiment of the present application further provides an electrical device, which includes the cylindrical battery cell 10 described above, and the cylindrical battery cell 10 is used to provide electrical energy to the electrical device.

[0239] According to some embodiments of this application, please refer to Figure 3 to Figure 12 .

[0240] The embodiment of the present application provides a cylindrical battery cell 10, which includes a shell 1 and an electrode terminal 3. The shell 1 has a first wall portion 16, and the first wall portion 16 is provided with a terminal hole. The electrode terminal 3 includes a main body 31 and a first limit portion 32, the main body 31 is inserted into the terminal hole, and the first limit portion 32 is connected to the main body 31. Along the thickness direction of the first wall portion 16, the first limit portion 32 is located on the side of the first wall portion 16 facing the inside of the shell 1, and the first limit portion 32 is configured to limit the main body 31 from escaping from the terminal hole in a direction away from the inside of the shell 1. Among them, along the thickness direction of the first wall portion 16, the outer peripheral surface of the first limit portion 32 is projected on the first wall portion 16 around the terminal hole. Along the radial direction of the terminal hole, the minimum distance between the outer peripheral surface and the hole wall of the terminal hole is A, and the radius of the shell 1 is R, which satisfies: 0.06≤A / R≤0.24. The first limiting portion 32 can prevent the main body 31 from detaching from the terminal hole in a direction away from the inside of the housing 1, thereby reducing the risk of the electrode terminal 3 detaching from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10. When A / R≥0.06, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is large, the area of ​​the first limiting portion 32 relative to the first wall 16 is large, and the limiting effect of the first limiting portion 32 is good, which further reduces the risk of the electrode terminal 3 detaching from the first wall 16 under the action of the internal air pressure of the cylindrical battery cell 10, thereby improving the reliability of the cylindrical battery cell 10. When A / R≤0.24, the minimum distance between the outer circumference of the first limiting portion 32 and the hole wall of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.06≦A / R≦0.24, both the reliability of the cylindrical battery cell 10 and the cost of the cylindrical battery cell 10 can be taken into consideration.

[0241] Optionally, 0.08≤A / R≤0.19. When A / R≥0.08, the minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall surface of the terminal hole is larger, the relative area of ​​the first limiting portion 32 and the first wall portion 16 is larger, and the limiting effect of the first limiting portion 32 is better, which can further reduce the risk of the electrode terminal 3 being separated from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10, and improve the reliability of the cylindrical battery cell 10. When A / R≤0.19, the minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall surface of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.08≤A / R≤0.19, it is more possible to take into account both the reliability and cost of the cylindrical battery cell 10.

[0242] 3.9mm≤A≤8.65mm. When A≥3.9mm, the minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall surface of the terminal hole is larger, the relative area of ​​the first limiting portion 32 and the first wall portion 16 is larger, and the limiting effect of the first limiting portion 32 is better, which can further reduce the risk of the electrode terminal 3 being separated from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10, and improve the reliability of the cylindrical battery cell 10. When A≤8.65mm, the minimum distance between the outer circumferential surface of the first limiting portion 32 and the hole wall surface of the terminal hole is not too large, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 3.9mm≤A≤8.65mm, it is more possible to take into account both the reliability and cost of the cylindrical battery cell 10.

[0243] Along the thickness direction of the first wall portion 16, the minimum thickness of the first limit portion 32 is H, which satisfies: 0.8mm≤H≤1.6mm. When H≥0.8mm, the minimum thickness of the first limit portion 32 is thicker, the strength of the first limit portion 32 is greater, the risk of the first limit portion 32 breaking is further reduced, and the risk of the electrode terminal 3 being separated from the first wall portion 16 under the action of the internal air pressure of the cylindrical battery cell 10 is further reduced, thereby improving the reliability of the cylindrical battery cell 10. When H≤2mm, the thickness of the first limit portion 32 is not too large, and the thickness of the first limit portion 32 is not too thick, which is not only conducive to reducing the material consumption of the electrode terminal 3 and reducing the cost of the cylindrical battery cell 10, but also conducive to reducing the occupation of the internal space of the cylindrical battery cell 10, reducing the weight of the cylindrical battery cell 10, and improving the energy density of the cylindrical battery cell 10. Therefore, when 0.4mm≤H≤2mm, it is more possible to take into account both the reliability of the cylindrical battery cell 10 and the energy density of the cylindrical battery cell 10.

[0244] The cylindrical battery cell 10 includes an electrode assembly 2, which is accommodated in a housing 1. The housing 1 includes a second wall portion 13 and a side wall 14. The second wall portion 13 is arranged at one end of the side wall 14 along the axial direction of the cylindrical battery cell 10. The side wall 14 is arranged around the second wall portion 13. A first flow guide channel 6 is formed between the electrode assembly 2 and the side wall 14. The second wall portion 13 includes a wall body 131 and a support portion 132. The wall body 131 is provided with a pressure relief mechanism 5. The support portion 132 is arranged around the outer edge of the wall body 131. Along the axial direction of the cylindrical battery cell 10, the support portion 132 protrudes from the wall body 131 in a direction close to the electrode assembly 2, and directly or indirectly abuts against the electrode assembly 2. The support portion 132 and the wall body 131 jointly define a flow guide space 133. The support portion 132 is provided with a second flow guide channel 1321, and the second flow guide channel 1321 connects the flow guide space 133 and the first flow guide channel 6. The abutting portion 132 of the second wall portion 13 abuts against the electrode assembly 2 directly or indirectly, and the abutting portion 132 can limit the electrode assembly 2, reducing the risk of the electrode assembly 2 moving along the axial direction of the cylindrical battery cell 10 in the housing 1. Since the abutting portion 132 is provided with a second guide channel 1321, the second guide channel 1321 connects the guide space 133 with the first guide channel 6. When the cylindrical battery cell 10 is in thermal runaway, the emission generated by the electrode assembly 2 flows into the first guide channel 6, and the emission can quickly flow into the guide space 133 through the second guide channel 1321 on the abutting portion 132, so that the gas pressure in the guide space 133 is quickly increased to quickly reach the bursting pressure of the pressure relief mechanism 5, shortening the time from the thermal runaway of the cylindrical battery cell 10 to the start of pressure relief of the cylindrical battery cell 10 through the pressure relief mechanism 5, so that the pressure relief mechanism 5 can be actuated in time, reducing the risk of explosion and fire of the cylindrical battery cell 10, and effectively improving the reliability of the cylindrical battery cell 10.

[0245] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope 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; The electrode terminal comprises a main body and a first limiting portion, wherein the main body is inserted into the terminal hole, the first limiting portion is connected to the main body, and along the thickness direction of the first wall portion, the first limiting portion is located on a side of the first wall portion facing the inside of the shell, and the first limiting portion is configured to limit the main body from being separated from the terminal hole in a direction away from the inside of the shell; Among them, along the thickness direction of the first wall portion, the projection of the outer peripheral surface of the first limiting portion on the first wall portion is arranged around the terminal hole, and along the radial direction of the terminal hole, the minimum distance between the outer peripheral surface and the hole wall surface of the terminal hole is A, and the radius of the outer shell is R, satisfying: 0.06≤A / R≤0.

24.

2. The cylindrical battery cell according to claim 1, characterized in that: 0.08≤A / R≤0.

19.

3. The cylindrical battery cell according to claim 1, characterized in that: 3mm≤A≤11mm, optionally, 3.9mm≤A≤8.65mm.

4. The cylindrical battery cell according to claim 1, characterized in that: 19mm≤R≤40mm.

5. 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 H, satisfying: 0.4 mm≤H≤2 mm, optionally, 0.8 mm≤H≤1.6 mm.

6. The cylindrical battery cell according to claim 1, characterized in that: The electrode terminal is made of aluminum.

7. The cylindrical battery cell according to claim 1, characterized in that: The electrode terminal includes a second limiting portion, the second limiting portion is connected to an end of the main body away from the inside of the shell, and the second limiting portion cooperates with the first limiting portion to clamp the first wall portion.

8. The cylindrical battery cell according to claim 1, characterized in that: The electrode terminal is provided with a liquid injection hole, and the liquid injection hole is used to inject electrolyte into the shell.

9. The cylindrical battery cell according to any one of claims 1 to 8, characterized in that: The housing comprises: The housing comprises a bottom wall and a side wall, wherein 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; an end cap for closing the opening; Wherein, the bottom wall is the first wall portion.

10. The cylindrical battery cell according to any one of claims 1 to 8, characterized in that: The cylindrical battery cell includes an electrode assembly, and the electrode assembly is accommodated in the housing; The housing comprises a second wall portion and a side wall, wherein the second wall portion is arranged at one end of the side wall along the axial direction of the cylindrical battery cell, the side wall is a cylindrical structure and is arranged around the second wall portion, and a first guide channel is formed between the electrode lug of the electrode assembly facing the second wall portion and the side wall; Among them, the second wall portion includes a wall body and a supporting portion, the wall body is provided with a pressure relief mechanism, the supporting portion is arranged around the outer edge of the wall body, along the axial direction of the cylindrical battery cell, the supporting portion protrudes from the wall body in a direction close to the electrode assembly, and directly or indirectly abuts against the electrode assembly, the supporting portion and the wall body together define a guide space, the supporting portion is provided with a second guide channel, and the second guide channel connects the guide space and the first guide channel.

11. The cylindrical battery cell according to claim 10, characterized in that: The abutting portion is provided with a plurality of the second flow guiding channels, and the plurality of the second flow guiding channels are arranged at intervals along the circumferential direction of the cylindrical battery cell.

12. The cylindrical battery cell according to claim 10, characterized in that: Along the axial direction of the cylindrical battery cell, the abutment portion has a abutment surface, and the abutment surface is the surface of the abutment portion closest to the electrode assembly. The second guide channel is a notch groove that penetrates the abutment portion along the radial direction of the cylindrical battery cell and extends to the abutment surface along the axial direction of the cylindrical battery cell.

13. The cylindrical battery cell according to claim 10, characterized in that: The abutting portion comprises: A plurality of protrusions are directly or indirectly pressed against the electrode assembly, and a second flow guide channel is formed between two adjacent protrusions along the circumference of the cylindrical battery cell.

14. The cylindrical battery cell according to claim 13, characterized in that: A flow guiding gap is formed between the side wall and the protruding portion, and the flow guiding gap communicates with two adjacent second flow guiding channels.

15. The cylindrical battery cell according to claim 13, characterized in that: The abutting portion further comprises: The main body is arranged around the outer edge of the wall body and protrudes from the wall body in a direction close to the electrode assembly. Along the axial direction of the cylindrical battery cell, the main body has a first surface facing the electrode assembly, and the protrusion protrudes from the first surface.

16. The cylindrical battery cell according to claim 15, characterized in that: Along the axial direction of the cylindrical battery cell, the wall body has a second surface, the second surface is a surface of the wall body closest to the electrode assembly, and the first surface is closer to the electrode assembly than the second surface.

17. The cylindrical battery cell according to claim 15, characterized in that: The abutment portion is provided with a first groove; along the axial direction of the cylindrical battery cell, the main body portion has a third surface arranged opposite to the first surface, the first surface is closer to the electrode assembly than the third surface, and the first groove is recessed from the third surface toward the direction close to the electrode assembly to form the protrusion protruding from the first surface on the side of the main body portion facing the electrode assembly.

18. The cylindrical battery cell according to claim 17, characterized in that: The first groove is a multi-level groove. Along the axial direction of the cylindrical battery cell, the first-level groove close to the electrode assembly in two adjacent levels of grooves is arranged on the groove bottom surface of the first-level groove away from the electrode assembly.

19. The cylindrical battery cell according to claim 18, characterized in that: The protrusion includes a first part and a second part, and the multi-stage groove includes: A first-level groove is recessed from the third surface toward the electrode assembly to form the first portion protruding from the first surface on the side of the body portion facing the electrode assembly, and along the axial direction of the cylindrical battery cell, the first portion has a fourth surface facing the electrode assembly; The second-stage groove is recessed from the groove bottom surface of the first-stage groove toward the direction close to the electrode assembly to form the second portion protruding from the fourth surface on the side of the first portion facing the electrode assembly.

20. The cylindrical battery cell according to claim 19, characterized in that: Along the radial direction of the cylindrical battery cell, the first part has a first side surface facing the inner circumference of the side wall, and the second part has a second side surface facing the inner circumference of the side wall, the first side surface is closer to the inner circumference of the side wall than the second side surface, and a flow guide gap is formed between the second side surface and the inner circumference of the side wall, and the flow guide gap connects two adjacent second flow guide channels.

21. The cylindrical battery cell according to claim 10, characterized in that: The battery cell further comprises: A current collecting member is disposed between the second wall portion and the electrode assembly along the axial direction of the cylindrical battery cell, the current collecting member electrically connects the electrode assembly and the second wall portion, the abutting portion directly abuts against the current collecting member, and the current collecting member directly abuts against the electrode assembly.

22. A battery, characterized in that: Comprising a cylindrical battery cell according to any one of claims 1-21.

23. An electrical equipment, characterized in that: It comprises a cylindrical battery cell according to any one of claims 1 to 21, wherein the cylindrical battery cell is used to provide electrical energy to the electrical device.

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