Battery monomer, battery and electric equipment

Abstract

The embodiment of the utility model provides a battery monomer, a battery and electric equipment. A battery cell includes a housing, an electrode assembly, a separator, and a pressure relief mechanism. The shell is provided with a first wall part, the pressure relief mechanism is arranged on the first wall part, the electrode assembly is contained in the shell, and the electrode assembly and the first wall part are oppositely arranged in the first direction. The separator is arranged between the first wall part and the electrode assembly, the separator is provided with an avoiding space, the projection of the pressure relief mechanism is at least partially located in the avoiding space in the first direction, and the avoiding space is configured to avoid the pressure relief mechanism. By arranging the separator between the first wall part and the electrode assembly, the distance between the electrode assembly and the first wall part is increased, the separator is provided with the avoidance space, and the avoidance space can avoid the pressure relief mechanism, so that the pressure relief mechanism is prevented from being directly impacted by the separator when the electrode assembly expands and deforms or the first wall part deforms due to external force; therefore, the service life of the single battery is effectively prolonged.

Description

Technical Field

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

[0002] In recent years, new energy vehicles have developed by leaps and bounds. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable and important role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also growing. As the demand for batteries increases, higher requirements are placed on the reliability of battery cells.

[0003] In battery technology, not only the reliability of battery cells but also the service life of battery cells need to be considered. Therefore, how to improve the service life of battery cells is an urgent problem to be solved in battery technology. Utility Model Content

[0004] The embodiments of the present application provide a battery cell, a battery and an electrical device, which can effectively increase the service life of the battery cell.

[0005] In the first aspect, an embodiment of the present application provides a battery cell, comprising a shell, a pressure relief mechanism, an electrode assembly and a separator; the shell has a first wall portion; the pressure relief mechanism is arranged on the first wall portion, and the pressure relief mechanism is configured to be at least partially opened when the battery cell is depressurized; the electrode assembly is accommodated in the shell, and the electrode assembly and the first wall portion are arranged opposite to each other along a first direction; the separator is arranged between the first wall portion and the electrode assembly, and the separator is provided with an avoidance space, and along the first direction, the projection of the pressure relief mechanism is at least partially located in the avoidance space, and the avoidance space is configured to avoid the pressure relief mechanism.

[0006] In the above technical solution, by arranging a separator between the first wall portion and the electrode assembly, the distance between the electrode assembly and the first wall portion is increased, thereby reducing the risk of damage to the pressure relief mechanism caused by the electrode assembly directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force. At the same time, since the separator is provided with an avoidance space, the avoidance space can avoid the pressure relief mechanism, thereby reducing the risk of damage to the pressure relief mechanism caused by the separator directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force, thereby effectively improving the service life of the battery cell.

[0007] In some embodiments, the escape space is a through hole that penetrates both ends of the separator along the first direction. The escape space can serve as an exhaust channel, which is conducive to the exhaust inside the battery cell located on the side of the separator facing the electrode assembly to flow to the pressure relief mechanism through the escape space.

[0008] In some embodiments, along the first direction, the projection of the separator does not overlap with the projection of the pressure relief mechanism, further reducing the influence of the separator on the pressure relief mechanism and further reducing the risk of the separator directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force, thereby damaging the pressure relief mechanism.

[0009] In some embodiments, the pressure relief mechanism includes a weak portion, which is configured to be at least partially split when the battery cell is depressurized, and the projection of the weak portion along the first direction is completely located in the avoidance space. When the battery cell is depressurized, the pressure relief mechanism can be split at the position of the weak portion to achieve at least partial opening of the pressure relief mechanism to release the pressure inside the battery cell. The projection of the weak portion is located in the avoidance space, which can effectively reduce the impact of the separator on the weak portion and reduce the risk of premature cracking of the weak portion due to impact.

[0010] In some embodiments, the housing includes a side wall, the side wall is arranged around the first wall portion, and the first wall portion is arranged at one end of the side wall along the first direction; a first pole ear is formed at one end of the electrode assembly close to the first wall portion along the first direction, a first guide channel is formed between the first pole ear and the side wall, a separator directly or indirectly abuts against the first pole ear along the first direction, and the separator is provided with a second guide channel, and the second guide channel connects the first guide channel and the escape space. When the battery cell is in thermal runaway, after the discharge located at the side of the electrode assembly flows to the first guide channel, the discharge can enter the escape space through the second guide channel on the separator, so that the discharge can quickly reach the vicinity of the pressure relief mechanism, so that the pressure relief mechanism can be opened and pressure relief in time, reducing the risk of explosion and fire of the battery cell, and effectively improving the reliability of the battery cell.

[0011] In some embodiments, the electrode assembly is formed with a first pole ear at one end close to the first wall along the first direction, and the separator includes a ring body and a plurality of protrusions; along the first direction, the ring body has a first surface and a second surface opposite to each other, and the avoidance space runs through the first surface and the second surface; the plurality of protrusions are arranged on the ring body at intervals along the circumference of the ring body, the protrusions at least partially protrude from the first surface, and a second flow guide channel is formed between the portions of two adjacent protrusions protruding from the first surface, and the second flow guide channel is connected to the avoidance space; wherein, along the first direction, one of the ring body and the protrusions directly or indirectly abuts against the first pole ear, and the first wall directly or indirectly abuts against the other of the ring body and the protrusions. Since one of the ring body and the protrusions directly or indirectly abuts against the first pole ear, and the first wall directly or indirectly abuts against the other of the ring body and the protrusions, the intermediate piece is supported between the first pole ear and the first wall, and the intermediate piece can limit the movement of the electrode assembly in the direction close to the first wall, thereby reducing the risk of the electrode assembly moving in the first direction in the housing. Since the second flow guide channel between two adjacent protrusions is connected to the escape space of the separator, when the battery cell is in thermal runaway, the emissions located on the side of the electrode assembly can enter the escape space through the second flow guide channel between the two adjacent protrusions, so that the emissions can quickly reach the vicinity of the pressure relief mechanism, so that the pressure relief mechanism can be opened and relieve pressure in time, reducing the risk of explosion and fire of the battery cell, and effectively improving the reliability of the battery cell. In other words, the second flow guide channel and the escape space can form a channel for emissions to pass between the electrode assembly and the first wall, so that the emissions located on the side of the electrode assembly can quickly flow to the pressure relief mechanism.

[0012] In some embodiments, the battery cell includes a first current collecting member, which is arranged between the separator and the first pole lug along the first direction, the first current collecting member electrically connects the separator and the first pole lug, and the first wall portion electrically connects the separator; along the first direction, the convex portion directly abuts against the first current collecting member, the first current collecting member directly abuts against the first pole lug, and the first wall portion directly abuts against the ring body. By arranging the first current collecting member between the separator and the first pole lug, the electrical connection between the first pole lug and the separator can be achieved, which reduces the difficulty of electrical connection between the first pole lug and the separator. The convex portion directly abuts against the first current collecting member, and the first wall portion directly abuts against the ring body, so that the second guide channel is formed on the side of the separator facing the electrode assembly, so that the emissions located on the side of the electrode assembly when the battery cell thermal runaway can enter the second guide channel more quickly.

[0013] In some embodiments, the ring body is welded to the first wall portion to form a first weld print area, and at least one convex portion is welded to the first current collecting member to form a second weld print area, and along the first direction, the projection of the first weld print area does not overlap with the projection of the second weld print area. In this way, the mutual interference between the first weld print area and the second weld print area can be reduced, and the risk of a cold weld when the ring body is welded to the first wall portion or the convex portion is welded to the first current collecting member is reduced.

[0014] In some embodiments, the convex portion includes a first part, the first part includes a first bend and a first connection part, the first bend is connected to the outer peripheral surface of the ring body, the first connection part is connected to the first bend, and the first connection part is at least partially located on the side of the first surface away from the second surface. The first part of this structure is a structure connected to the outer peripheral surface of the ring body and partially bent on the side of the first surface away from the second surface. The structure of the first part is simple, thereby reducing the difficulty of forming the convex portion. In addition, since the first bend is connected to the outer peripheral surface of the ring body, the first bend does not occupy the internal space of the ring body, which can increase the avoidance space, improve the avoidance ability of the avoidance space for the pressure relief mechanism and the diversion ability for the flow of emissions.

[0015] In some embodiments, along the first direction, a gap is provided between the first connection portion and the first surface. A first gap can be formed between the first connection portion and the first surface, so that the separator can play a buffering role between the first wall portion and the electrode assembly to absorb the impact force on the first wall portion, and reduce the risk of damage to the electrode assembly caused by external impact on the first wall portion. In addition, a first gap can be formed between the first connection portion and the first surface to connect two adjacent second guide channels. When the emissions located on the side of the electrode assembly flow to a certain second guide channel, the emissions can flow to another adjacent second guide channel through the first gap, so that the emissions can enter the avoidance space more quickly.

[0016] In some embodiments, the first connecting portion includes a second bending portion and a plurality of first stacking portions, the plurality of first stacking portions are located on the side of the first surface away from the second surface, and the plurality of first stacking portions are arranged along the first direction; the second bending portion connects two adjacent first stacking portions. This structure can increase the height of the convex portion protruding from the first surface, thereby increasing the size of the second guide channel in the first direction, and improving the smoothness of the flow of the discharge in the second guide channel.

[0017] In some embodiments, a gap is set between two adjacent first laminated parts along the first direction. A second gap can be formed between the two adjacent first laminated parts, so that the first connecting part can play a buffering role between the first wall part and the electrode assembly to absorb the impact force on the first wall part, and reduce the risk of damage to the electrode assembly caused by external impact on the first wall part. In addition, the second gap formed between the two adjacent first laminated parts can connect the two adjacent second guide channels. When the emissions located on the side of the electrode assembly flow to a certain second guide channel, the emissions can flow to another adjacent second guide channel through the second gap, so that the emissions can enter the avoidance space more quickly.

[0018] In some embodiments, along the first direction, a first stacked portion farthest from the first surface is connected to the first bending portion; or, along the first direction, a first stacked portion closest to the first surface is connected to the first bending portion.

[0019] In some embodiments, the first part is formed by bending a plate in one piece. The first part of this structure has high structural stability and low molding difficulty.

[0020] In some embodiments, the convex portion includes a second portion, the second portion includes a third bend portion and a second connection portion, the third bend portion is connected to the inner circumference of the ring body, the second connection portion is connected to the third bend portion, the second connection portion is at least partially located on the side of the first surface away from the second surface, and the second connection portion and the first connection portion are arranged along the first direction; wherein the first connection portion is closer to the first surface than the second connection portion along the first direction; or, the second connection portion is closer to the first surface than the first connection portion along the first direction. The second connection portion of the second portion is arranged along the first direction with the first connection portion of the first portion, which can increase the height of the convex portion protruding from the first surface, thereby increasing the size of the second guide channel in the first direction, and improving the smoothness of the flow of the discharge in the second guide channel.

[0021] In some embodiments, the convex portion includes a second part, the second part includes a third bend and a second connecting portion, the third bend is connected to the inner circumference of the ring body, the second connecting portion is connected to the third bend, and the second connecting portion is at least partially located on the side of the first surface away from the second surface. The second part of this structure is a structure connected to the inner circumference of the ring body and partially bent on the side of the first surface away from the second surface. The structure of the second part is simple, thereby reducing the difficulty of forming the convex portion. In addition, since the third bend is connected to the inner circumference of the ring body, the size of the third bend along the circumference of the ring body can be reduced, and the material used for the third bend can be reduced.

[0022] In some embodiments, along the first direction, the second connection portion and the first surface gap are arranged. A third gap can be formed between the second connection portion and the first surface, so that the separator can play a buffering role between the first wall portion and the electrode assembly to absorb the impact force on the first wall portion, and reduce the risk of damage to the electrode assembly caused by external impact on the first wall portion. In addition, a third gap can be formed between the second connection portion and the first surface to connect two adjacent second guide channels. When the emissions located on the side of the electrode assembly flow to a certain second guide channel, the emissions can flow to another adjacent second guide channel through the third gap, so that the emissions can enter the avoidance space more quickly.

[0023] In some embodiments, the second connecting portion includes a fourth bending portion and a plurality of second stacking portions, the plurality of second stacking portions are located on the side of the first surface away from the second surface, and the plurality of second stacking portions are arranged along the first direction; the fourth bending portion connects two adjacent second stacking portions. This structure can increase the height of the protrusion protruding from the first surface, thereby increasing the size of the second guide channel in the first direction, and improving the smoothness of the flow of the discharge in the second guide channel.

[0024] In some embodiments, a gap is set between two adjacent second laminated parts along the first direction. A fourth gap can be formed between the two adjacent second laminated parts, so that the second connecting part can play a buffering role between the first wall part and the electrode assembly to absorb the impact force on the first wall part, and reduce the risk of damage to the electrode assembly caused by external impact on the first wall part. In addition, the fourth gap formed between the two adjacent second laminated parts can connect the two adjacent second guide channels. When the emissions located on the side of the electrode assembly flow to a certain second guide channel, the emissions can flow to another adjacent second guide channel through the fourth gap, so that the emissions can enter the avoidance space more quickly.

[0025] In some embodiments, along the first direction, a second stacked portion farthest from the first surface is connected to the third bending portion; or, along the first direction, a second stacked portion closest to the first surface is connected to the third bending portion.

[0026] In some embodiments, the second part is formed by bending a plate in one piece. The second part of this structure has high structural stability and low molding difficulty.

[0027] In some embodiments, along the first direction, the minimum thickness of the ring body is D, D ≥ 0.3 mm. The ring body has a sufficient thickness, which, on the one hand, provides the ring body with sufficient structural strength, and, on the other hand, provides a sufficiently large distance between the electrode assembly and the first wall portion, thereby further reducing the risk of the electrode assembly directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force, thereby causing damage to the pressure relief mechanism.

[0028] In some embodiments, the separator electrically connects the first wall portion and the first electrode ear, and along the circumference of the ring body, the sum of the maximum dimensions of all protrusions is A1, and the sum of the maximum dimensions of all second flow guide channels is A2, 0.1≤A1 / (A1+A2)≤0.8. A1 / (A1+A2)≥0.1, so that the proportion of the dimensions of all protrusions in the circumference of the ring body is not too small, so that all protrusions as a whole have sufficient contact area with the components they directly abut against, and stable flow is achieved; A1 / (A1+A2)≤0.8, so that the proportion of the dimensions of all second flow guide channels in the circumference of the ring body is not too small, so that the discharge on the side of the electrode assembly can quickly enter the avoidance space, so that the pressure relief mechanism can open and relieve pressure more promptly.

[0029] In some embodiments, the separator electrically connects the first wall portion and the electrode assembly. The separator not only serves to separate the first wall portion and the electrode assembly, but also serves to electrically connect the first wall portion and the electrode assembly.

[0030] In some embodiments, the battery cell includes a first current collecting member, the first current collecting member is disposed between the separator and the electrode assembly along a first direction, the first current collecting member electrically connects the separator and the electrode assembly, and along the first direction, the projection of the first current collecting member covers the avoidance space. By disposing the first current collecting member between the separator and the electrode assembly, the electrical connection between the electrode assembly and the separator can be achieved, which reduces the difficulty of electrical connection between the electrode assembly and the separator.

[0031] In some embodiments, the separator is welded to the first wall portion to form a first weld print area, and the separator is welded to the first current collecting member to form a second weld print area, and along the first direction, the projection of the first weld print area does not overlap with the projection of the second weld print area. In this way, the mutual interference between the first weld print area and the second weld print area can be reduced, and the risk of a cold weld when the separator is welded to the first wall portion or the separator is welded to the first current collecting member is reduced.

[0032] In some embodiments, a first pole ear is formed at one end of the electrode assembly close to the first wall along the first direction, and the material of the first pole ear is different from that of the first wall; wherein the material of the first current collecting member is the same as that of the first pole ear, and the first current collecting member is welded to the first pole ear; the material of the separator is the same as that of the first wall, and the separator is welded to the first wall; the first current collecting member is compositely connected to the separator. The material of the first current collecting member is the same as that of the first pole ear, which can reduce the difficulty of welding the first current collecting member and the first pole ear, improve the firmness of the first current collecting member and the first pole ear after welding, and achieve stable flow between the first current collecting member and the first pole ear; the material of the separator is the same as that of the first wall, which can reduce the difficulty of welding the separator and the first wall, improve the firmness of the separator and the first wall after welding, and achieve stable flow between the separator and the first wall; the first current collecting member is compositely connected to the separator, which achieves stable flow between the first current collecting member and the separator, and then achieves stable flow between the first wall and the first pole ear.

[0033] In some embodiments, the electrode assembly is provided with a first central hole, the first current collecting member is provided with a second central hole, and the second central hole is connected to the first central hole and the escape space. When the battery cell is in thermal runaway, the emissions generated by the electrode assembly can enter the escape space through the first central hole and the second central hole in sequence, so that the pressure relief mechanism can be opened and relieved more promptly.

[0034] In some embodiments, the first wall portion includes a wall body and abutment portion, the wall body is provided with a pressure relief mechanism, and the abutment portion is disposed around the outer edge of the wall body; along the first direction, the abutment portion protrudes from the wall body in a direction close to the electrode assembly, and directly or indirectly abuts against the separator. In this way, the distance between the pressure relief mechanism and the separator can be increased, thereby further reducing the influence of the separator on the pressure relief mechanism, and further reducing the risk of the separator directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force, thereby causing damage to the pressure relief mechanism.

[0035] In some embodiments, the housing includes a side wall separately provided with the first wall portion, the side wall is provided around the first wall portion, and the first wall portion is provided at one end of the side wall along the first direction; at least a portion of the abutment portion is accommodated in the side wall and forms a positioning match with the side wall. The first wall portion and the side wall are separately provided, which facilitates the installation of the electrode assembly into the housing. By forming a positioning match between the abutment portion and the side wall, the assembly difficulty of the first wall portion and the side wall can be effectively improved.

[0036] In some embodiments, the pressure relief mechanism is integrally formed with the first wall portion; or, the pressure relief mechanism is separately arranged with the first wall portion, and the pressure relief mechanism is installed on the first wall portion. The pressure relief mechanism is integrally formed with the first wall portion to form an integrated pressure relief mechanism, which has higher reliability, eliminates the installation process of the pressure relief mechanism, and has better economy. The pressure relief mechanism is separately arranged with the first wall portion, and the pressure relief mechanism is installed on the first wall portion, so that the pressure relief mechanism is a component independent of the shell, and the pressure relief mechanism and the shell can be produced and assembled separately, with low production difficulty and high efficiency.

[0037] In some embodiments, the housing includes a shell and an end cover; the shell is formed with an opening at at least one end along the first direction; the end cover closes the opening; wherein at least one end cover is a first wall portion. At least one end cover is a first wall portion, so that at least one end cover is provided with a pressure relief mechanism, which reduces the difficulty of molding or installing the pressure relief mechanism.

[0038] In some embodiments, the battery cells are cylindrical battery cells.

[0039] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell provided by any embodiment of the first aspect.

[0040] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery cell provided by any one embodiment of the first aspect, wherein the battery cell is used to provide electrical energy to the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] 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.

[0042] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0043] Figure 2 An exploded view of a battery provided for some embodiments of the present application;

[0044] Figure 3 An exploded view of a battery cell provided for some embodiments of the present application;

[0045] Figure 4 for Figure 3 A cross-sectional view of a battery cell is shown;

[0046] Figure 5 for Figure 4 A partial enlarged view of a battery cell shown;

[0047] Figure 6 A partial view of a battery cell provided for some other embodiments of the present application;

[0048] Figure 7 An exploded view of a battery cell provided in some other embodiments of the present application;

[0049] Figure 8 for Figure 7 A cross-sectional view of a battery cell is shown;

[0050] Fig. 9 for Figure 8 A partial enlarged view of a battery cell shown;

[0051] Fig.10 for Fig. 9 an axonometric view of the divider shown;

[0052] Fig.11 for Fig.10 a cross-sectional view of the separator shown;

[0053] Fig.12 for Fig.11 A view of the separator shown;

[0054] Fig.13 A partial view of a battery cell (the convex portion includes a first portion, and the first portion is connected to the outer peripheral surface of the ring body) provided in some embodiments of the present application;

[0055] Fig.14 for Fig.13 an axonometric view of the divider shown;

[0056] Fig.15 A partial view of a battery cell (the convex portion includes a first portion, and the first portion is connected to the outer peripheral surface of the ring body) provided in some other embodiments of the present application;

[0057] Fig.16 for Fig.15 an axonometric view of the divider shown;

[0058] Fig.17 A partial view of a battery cell (the convex portion includes a first portion and a second portion, the first portion is connected to the outer circumference of the ring body, and the second portion is connected to the inner circumference of the ring body) provided in some embodiments of the present application;

[0059] Fig.18 for Fig.17 an axonometric view of the divider shown;

[0060] Fig.19A partial view of a battery cell (the convex portion includes a first portion and a second portion, the first portion is connected to the outer circumference of the ring body, and the second portion is connected to the inner circumference of the ring body) provided in some other embodiments of the present application;

[0061] Fig. 20 for Fig.19 an axonometric view of the divider shown;

[0062] Fig.21 A partial view of a battery cell (a first portion connected to the inner circumference of the ring body) provided in some embodiments of the present application;

[0063] Fig. 22 for Fig.21 an axonometric view of the divider shown;

[0064] Fig.23 A partial view of a battery cell (the convex portion includes a second portion, and the second portion is connected to the inner circumference of the ring body) provided in some other embodiments of the present application;

[0065] Fig.24 for Fig.23 an axonometric view of the divider shown;

[0066] Fig.25 A partial view of a battery cell (the convex portion includes a second portion, and the second portion is connected to the inner circumference of the ring body) provided in some other embodiments of the present application;

[0067] Fig.26 for Fig.25 an axonometric view of the divider shown;

[0068] Fig. 27 A schematic structural diagram of a first wall portion provided in some embodiments of the present application;

[0069] Fig.28 for Fig. 27 A cross-sectional view of the first wall portion is shown.

[0070] Icons: 1-shell; 11-shell; 12-end cover; 13-first wall; 131-pressure relief mechanism; 1311-weak part; 1312-pressure relief area; 132-wall body; 1321-third surface; 133-abutment part; 134-flow guide space; 135-edge part; 136-pressure relief groove; 137-groove; 138-bottom wall of the groove; 1381-recess; 1382-reinforcement rib ; 14-side wall; 141-inner circumference of the side wall; 2-electrode assembly; 21-main body; 22-first pole ear; 23-second pole ear; 24-first center hole; 3-electrode terminal; 4-separator; 41-avoidance space; 42-second flow guide channel; 43-ring body; 431-first surface; 432-second surface; 433-outer circumference of the ring body; 434-inner circumference of the ring body; 44-convex portion; 441-first part; 4411-first bending part; 4412-first connecting part; 44121-second bending part; 44122-first stacking part; 4413-first gap; 4414-second gap; 442-second part; 4421-third bending part; 4422-second connecting part; 44221-fourth bending part; 44222-second stacking part; 4423-third gap; 4424-fourth gap; 45-first weld print area; 46-second weld print area; 5-first current collecting component; 51-second center hole; 6-second current collecting component; 7-first guide channel; 10-battery cell; 20-housing; 201-first housing; 202-second housing; 100-battery; 200-controller; 300-motor; 1000-vehicle; Z-first direction; X-circumference of the ring body. DETAILED DESCRIPTION

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] The term "plurality" used in the present application refers to two or more (including two).

[0077] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0078] 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.

[0079] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to reduce the risk of short circuit between the positive and negative electrodes, while allowing active ions to pass through.

[0080] 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.

[0081] 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.

[0082] 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.).

[0083] 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.

[0084] 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.

[0085] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0086] 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.).

[0087] 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.

[0088] 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.

[0089] As an example, the negative electrode active material may adopt the negative electrode active material for 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.

[0090] 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.

[0091] In some embodiments, the separator is a separator membrane, which can be any known porous separator membrane with good chemical stability and mechanical stability.

[0092] 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.

[0093] 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.

[0094] In some embodiments, the battery cell further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The electrolyte can be liquid, gel or solid. Among them, the liquid electrolyte includes an electrolyte salt and a solvent.

[0095] 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.

[0096] 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.

[0097] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0098] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0099] 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.

[0100] 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.

[0101] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0102] 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.

[0103] In some embodiments, the electrode assembly is a laminate structure.

[0104] 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.

[0105] 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.

[0106] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded sections.

[0107] 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.

[0108] 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.

[0109] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0110] 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.

[0111] In some embodiments, the 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.

[0112] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a polygonal battery cell, such as a hexagonal battery cell.

[0113] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0114] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0115] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0116] 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.

[0117] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0118] In some embodiments, in order to improve the reliability of the battery cell, a pressure relief mechanism may be generally provided on the wall of the battery cell housing, and when the battery cell thermally runs away, the pressure inside the battery cell may be released through the pressure relief mechanism.

[0119] The pressure relief mechanism refers to an element or component that can at least partially open to release the internal pressure when the internal pressure of the battery cell 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 battery cell.

[0120] When the pressure relief mechanism is opened, the high-temperature and high-pressure substances inside the battery cell will be discharged from the opened part as exhaust. In this way, the pressure of the battery cell can be relieved under controllable pressure, thereby avoiding potential more serious accidents.

[0121] The emissions from the 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.

[0122] In a general battery cell, after the electrode assembly is installed in the outer shell, the electrode assembly generally directly rests on the wall of the outer shell provided with a pressure relief mechanism. When the electrode assembly expands and deforms or the wall provided with the pressure relief mechanism is deformed by external force, the wall provided with the pressure relief mechanism will be squeezed with the electrode assembly. The pressure relief mechanism is easily damaged and fails after being impacted by the electrode assembly, which affects the service life of the battery cell.

[0123] In view of this, an embodiment of the present application provides a battery cell, wherein a separator is provided between an electrode assembly and a first wall portion of a housing provided with a pressure relief mechanism, and an escape space is provided on the separator, and the pressure relief mechanism is avoided through the escape space.

[0124] In such a battery cell, by arranging a separator between the first wall portion and the electrode assembly, the distance between the electrode assembly and the first wall portion is increased, thereby reducing the risk of damage to the pressure relief mechanism caused by the electrode assembly directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force. At the same time, since the separator is provided with an avoidance space, the avoidance space can avoid the pressure relief mechanism, thereby reducing the risk of damage to the pressure relief mechanism caused by the separator directly impacting the pressure relief mechanism when the electrode assembly expands and deforms or the first wall portion is deformed by external force, thereby effectively improving the service life of the battery cell.

[0125] The battery cells described in the embodiments of the present application are suitable for batteries and electrical equipment using the battery cells.

[0126] 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.

[0127] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0128] Please refer to Figure 1 , Figure 1 The 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.

[0129] 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 .

[0130] 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.

[0131] Please refer to Figure 2 , Figure 2 The exploded view of the battery 100 provided in some embodiments of the present application. The battery 100 includes a battery cell 10 and a box body 20, and the battery cell 10 is accommodated in the box body 20.

[0132] Among them, the box body 20 is a component for accommodating the battery cell 10, and the box body 20 provides a storage space for the 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, and the first box body 201 and the second box body 202 cover each other to define a storage space for accommodating the 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, and the open side of the second box body 202 covers the open side of the first box body 201, so as to form 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, and the second box body 202 covers the open side of the first box body 201, so as to form 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.

[0133] In the battery 100, there may be one or more battery cells 10. If there are more than one battery cell 10, the battery cells 10 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the battery cells 10 are both connected in series and in parallel. The battery modules may be connected in series, in parallel, or in a mixed connection to form a battery module, and then the battery modules may be connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 20. Alternatively, all the battery cells 10 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by all the battery cells 10 may be accommodated in the box 20.

[0134] Please refer to Figure 3 and Figure 4 , Figure 3An exploded view of a battery cell 10 provided in some embodiments of the present application; Figure 4 for Figure 3 The battery cell 10 is a cross-sectional view of the battery cell 10. The battery cell 10 may include a housing 1 and an electrode assembly 2, wherein the electrode assembly 2 is accommodated in the housing 1.

[0135] In some embodiments, the housing 1 may include a shell 11 and an end cover 12 , wherein the shell 11 has an opening and the end cover 12 closes the opening of the shell 11 .

[0136] The housing 11 is a component for accommodating the electrode assembly 2. The housing 11 may be a hollow structure with an opening formed at one end, or a hollow structure with openings formed at opposite ends. The housing 11 may be in various shapes, such as a cylindrical shape, a rectangular parallelepiped shape, etc. The housing 11 may be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, etc.

[0137] The end cap 12 is a component that closes the opening of the shell 11 to isolate the internal environment of the battery cell 10 from the external environment. The end cap 12 and the shell 11 together define a receiving space for accommodating the electrode assembly 2, the electrolyte and other components. The end cap 12 can be connected to the shell 11 by welding or crimping to close the opening of the shell 11. The shape of the end cap 12 can be adapted to the shape of the shell 1. For example, the shell 11 is a rectangular parallelepiped structure, and the end cap 12 is a rectangular plate structure adapted to the shell 1. For another example, the shell 11 is cylindrical, and the end cap 12 is a circular plate structure adapted to the shell 11. The material of the end cap 12 can also be a variety of materials, such as copper, iron, aluminum, steel, aluminum alloy, etc. The material of the end cap 12 and the shell 11 can be the same or different.

[0138] In the embodiment where the housing 11 is opened at one end, one end cap 12 may be provided. In the embodiment where the housing 11 is opened at two opposite ends, two end caps 12 may be provided, and the two end caps 12 respectively close the two openings of the housing 11, and the two end caps 12 and the housing 11 together define a receiving space.

[0139] In some embodiments, the battery cell 10 may further include an electrode terminal 3, which is disposed on the housing 1 and is used to be electrically connected to the tab of the electrode assembly 2 to input or output the electrical energy of the battery cell 10. The electrode terminal 3 may be disposed on the shell 11 of the housing 1 or on the end cover 12 of the housing 1. The electrode terminal 3 may be directly connected to the tab, for example, the electrode terminal 3 may be welded to the tab. The electrode terminal 3 may also be indirectly connected to the tab.

[0140] Please refer to Figure 5 , Figure 5 for Figure 4A partial enlarged view of the battery cell 10 shown. An embodiment of the present application provides a battery cell 10, which includes a shell 1, an electrode assembly 2, a separator 4 and a pressure relief mechanism 131. The shell 1 has a first wall portion 13, and the pressure relief mechanism 131 is arranged on the first wall portion 13. The pressure relief mechanism 131 is configured to be at least partially opened when the battery cell 10 is depressurized. The electrode assembly 2 is accommodated in the shell 1, and the electrode assembly 2 and the first wall portion 13 are arranged opposite to each other along the first direction Z. The separator 4 is arranged between the first wall portion 13 and the electrode assembly 2, and the separator 4 is provided with an avoidance space 41. Along the first direction Z, the projection of the pressure relief mechanism 131 is at least partially located in the avoidance space 41, and the avoidance space 41 is configured to avoid the pressure relief mechanism 131.

[0141] The housing 1 may be cylindrical, prismatic, etc. There may be only one or more first walls 13 in the housing 1. An opening is formed at at least one end of the housing 11 along the first direction Z. In the embodiment where the housing 11 is opened at only one end, only the end cap 12 may be the first wall 13, only the wall of the housing 11 opposite to the end cap 12 may be the first wall 13, or both the end cap 12 and the wall of the housing 11 opposite to the end cap 12 may be the first wall 13. In the embodiment where the housing 11 is opened at both opposite ends, any one of the two end caps 12 may be the first wall 13, or both end caps 12 may be the first wall 13.

[0142] The first direction Z is the arrangement direction of the electrode assembly 2 and the first wall portion 13, and the first direction Z may be parallel to the thickness direction of the first wall portion 13. In the embodiment where the housing 1 is cylindrical, that is, the battery cell 10 is a cylindrical battery cell, the first direction Z may be parallel to the axial direction of the housing 1. The electrode assembly 2 may be a winding structure or a laminated structure. If the electrode assembly 2 is a winding structure, the first direction Z may be parallel to the extension direction of the winding centerline of the electrode assembly 2.

[0143] The electrode assembly 2 may include a main body 21, a first pole tab 22, and a second pole tab 23. The first pole tab 22 and the second pole tab 23 have opposite polarities. The first pole tab 22 and the second pole tab 23 may be connected to opposite ends of the main body 21 along the first direction Z, or the first pole tab 22 and the second pole tab 23 may be connected to the same end of the main body 21 along the first direction Z. One of the first pole tab 22 and the second pole tab 23 is a positive pole tab, and the other is a negative pole tab. The main body 21 may be a portion of the electrode assembly 2 corresponding to a region where the pole piece is coated with an active material layer, the positive pole tab may be a portion of the positive pole piece that is not coated with a positive active material layer, and the negative pole tab may be a portion of the negative pole piece that is not coated with a negative active material layer.

[0144] The separator 4 may be an insulating member disposed between the first wall portion 13 and the electrode assembly 2 to achieve insulation isolation between the electrode assembly 2 and the first wall portion 13, and the insulating member may be made of plastic, rubber, or other materials. As an example, the shell 11 is opened at only one end, and the end cap 12 is the first wall portion 13. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively disposed at the two ends of the main body 21, and the wall portion opposite to the shell 11 and the end cap 12 is provided with an electrode terminal 3, and the electrode terminal 3 is insulated from the shell 11, and the second pole ear 23 of the electrode assembly 2 is electrically connected to the electrode terminal 3, and the first pole ear 22 of the electrode assembly 2 is electrically connected to the shell 11, and a separator 4 is disposed between the first pole ear 22 and the end cap 12, and the separator 4 insulates and isolates the first pole ear 22 from the end cap 12.

[0145] The separator 4 may also be a conductive member disposed between the first wall portion 13 and the electrode assembly 2 to achieve electrical connection between the electrode assembly 2 and the first wall portion 13. The conductive member may be a conductive metal, such as copper, iron, aluminum, steel, aluminum alloy, etc. The separator 4 may be directly connected to the electrode assembly 2 or indirectly connected to achieve electrical connection between the separator 4 and the electrode assembly 2; the separator 4 may be directly connected to the first wall portion 13 or indirectly connected to achieve electrical connection between the separator 4 and the first wall portion 13. As an example, Figure 4 As shown, the shell 11 is opened at only one end, and the end cover 12 is a first wall portion 13. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at the two ends of the main body 21, and the wall portion opposite to the shell 11 and the end cover 12 is provided with an electrode terminal 3, and the electrode terminal 3 is insulated and connected to the shell 11. The second pole ear 23 of the electrode assembly 2 is electrically connected to the electrode terminal 3 through the second current collecting member 6. A separator 4 is provided between the first pole ear 22 of the electrode assembly 2 and the end cover 12, and the separator 4 electrically connects the first pole ear 22 with the end cover 12.

[0146] The avoidance space 41 is a space on the partition 4 for avoiding the pressure relief mechanism 131. The projection of the pressure relief mechanism 131 along the first direction Z may be partially located in the avoidance space 41, or may be completely located in the avoidance space 41. The avoidance space 41 may be a through hole that penetrates the two opposite ends of the partition 4 along the first direction Z, or may be an avoidance groove provided on the side of the partition 4 facing the first wall portion 13. In the embodiment where the first wall portion 13 is indirectly connected to the partition 4, for example, the first wall portion 13 is connected to the partition 4 through an intermediate member, and the intermediate member may be an annular structure, and the center hole of the intermediate member also plays a role in avoiding the pressure relief mechanism 131, so as to realize that the projection of the pressure relief mechanism 131 along the first direction Z is located in the avoidance space 41.

[0147] The pressure relief mechanism 131 may be a component that is separate from the first wall portion 13 . The pressure relief mechanism 131 is installed on the first wall portion 13 . The pressure relief mechanism 131 may be a burst-proof disk, a pressure relief valve, etc. The pressure relief mechanism 131 may also be integrally formed with the first wall portion 13 .

[0148] In the embodiment of the present application, by arranging the separator 4 between the first wall portion 13 and the electrode assembly 2, the distance between the electrode assembly 2 and the first wall portion 13 is increased, thereby reducing the risk of the electrode assembly 2 directly impacting the pressure relief mechanism 131 when the electrode assembly 2 expands and deforms or the first wall portion 13 is deformed by external force, thereby causing damage to the pressure relief mechanism 131. At the same time, since the separator 4 is provided with an avoidance space 41, the avoidance space 41 can avoid the pressure relief mechanism 131, thereby reducing the risk of the separator 4 directly impacting the pressure relief mechanism 131 when the electrode assembly 2 expands and deforms or the first wall portion 13 is deformed by external force, thereby causing damage to the pressure relief mechanism 131, thereby effectively improving the service life of the battery cell 10.

[0149] In some embodiments, please refer to Figure 6 The avoidance space 41 is a through hole that passes through both ends of the partition 4 along the first direction Z.

[0150] The escape space 41 may be a through hole that penetrates both ends of the separator 4 only along the first direction Z, the through hole may be a circular hole, a square hole, etc., and the separator 4 may be an annular structure. The escape space 41 may also be a through hole that penetrates both ends of the separator 4 along the first direction Z and extends to the outer peripheral surface of the separator 4 in a direction perpendicular to the first direction Z, and the separator 4 may be a U-shaped structure, a semi-annular structure, etc.

[0151] In this embodiment, the avoidance space 41 runs through both ends of the separator 4 along the first direction Z. The avoidance space 41 can serve as an exhaust channel, which is beneficial for the exhaust inside the battery cell 10 located on the side of the separator 4 facing the electrode assembly 2 to flow to the pressure relief mechanism 131 through the avoidance space 41.

[0152] In some embodiments, please refer to Figure 6 , Figure 6 Partial views of battery cells 10 provided in some other embodiments of the present application. Along the first direction Z, the projection of the separator 4 does not overlap with the projection of the pressure relief mechanism 131. In other words, the orthographic projections of the separator 4 and the pressure relief mechanism 131 in a plane perpendicular to the first direction Z do not overlap.

[0153] The avoidance space 41 may be a through hole that passes through both ends of the partition 4 along the first direction Z, so that the projection of the partition 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131 along the first direction Z. The partition 4 may be an annular structure, a U-shaped structure, a semi-annular structure, etc. It is understood that along the first direction Z, the projection of the partition 4 does not overlap with the projection of the pressure relief mechanism 131, so that the projection of the pressure relief mechanism 131 along the first direction Z is completely located in the avoidance space 41.

[0154] In this embodiment, the projection of the separator 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131 along the first direction Z, which further reduces the influence of the separator 4 on the pressure relief mechanism 131 and further reduces the risk of damage to the pressure relief mechanism 131 caused by the separator 4 directly impacting the pressure relief mechanism 131 when the electrode assembly 2 expands and deforms or the first wall portion 13 is deformed by external force.

[0155] In some embodiments, the pressure relief mechanism 131 includes a weak portion 1311 , which is configured to be at least partially split when the battery cell 10 is depressurized, and along the first direction Z, the projection of the weak portion 1311 is completely located in the avoidance space 41 .

[0156] It can be understood that, along the first direction Z, the projection of the weak portion 1311 does not overlap with the projection of the partition 4 .

[0157] The weak portion 1311 is a portion of the pressure relief mechanism 131 that is lower in strength than other areas. The weak portion 1311 may be formed by setting a groove on the pressure relief mechanism 131, or by heat treating a part of the pressure relief mechanism 131 so that the strength of the local area is weakened to form a corresponding weak portion.

[0158] As an example, in Figure 6 In the illustrated embodiment, the pressure relief mechanism 131 is integrally formed with the first wall portion 13, and the pressure relief mechanism 131 is provided with a pressure relief groove 136 ( Figure 6 (not shown), the pressure relief mechanism 131 forms a weak portion 1311 corresponding to the position where the pressure relief groove 136 is set, and the bottom wall of the pressure relief groove 136 can be the weak portion 1311.

[0159] When the battery cell 10 is depressurized, the pressure relief mechanism 131 may be cracked at the position of the weak portion 1311 to achieve at least partial opening of the pressure relief mechanism 131 to release the pressure inside the battery cell 10. The projection of the weak portion 1311 is located in the avoidance space 41, which can effectively reduce the influence of the separator 4 on the weak portion 1311 and reduce the risk of premature cracking of the weak portion 1311 due to impact.

[0160] In some embodiments, please refer to Figure 7-10 , Figure 7An exploded view of a battery cell 10 (a first portion 441 is connected to an outer peripheral surface 433 of the ring body) provided in some embodiments of the present application; Figure 8 for Figure 7 A cross-sectional view of a battery cell 10 is shown; Fig. 9 for Figure 8 A partial enlarged view of the battery cell 10 shown; Fig.10 for Fig. 9 The isometric view of the separator 4 is shown. The housing 1 includes a side wall 14, and the side wall 14 is arranged around the first wall portion 13, and the first wall portion 13 is arranged at one end of the side wall 14 along the first direction Z. A first electrode ear 22 is formed at one end of the electrode assembly 2 close to the first wall portion 13 along the first direction Z, and a first guide channel 7 is formed between the first electrode ear 22 and the side wall 14. The separator 4 directly or indirectly abuts against the first electrode ear 22 along the first direction Z, and the separator 4 is provided with a second guide channel 42, and the second guide channel 42 connects the first guide channel 7 and the avoidance space 41.

[0161] The side wall 14 may be cylindrical, so that the battery cell 10 is a cylindrical battery cell; the side wall 14 may also be cuboid, so that the battery cell 10 is a square shell battery cell 10 or a blade battery cell 10. The side wall 14 and the first wall portion 13 may be integrally formed, and the side wall 14 and the first wall portion 13 constitute the housing 11, and the end of the side wall 14 away from the first wall portion 13 along the first direction Z forms an opening of the housing 11; the side wall 14 and the first wall portion 13 may also be separately provided, and the first wall portion 13 is the end cover 12, and the end of the side wall 14 close to the first wall portion 13 along the first direction Z forms an opening of the housing 11, and the first wall portion 13 and the side wall 14 may be connected by welding, bonding, crimping, etc.

[0162] The first flow guide channel 7 may be a gap formed between the outer circumference of the pole ear and the inner circumference 141 of the side wall. After the electrode assembly 2 is loaded into the housing 1, a gap communicating with the first flow guide channel 7 may also be formed between the outer circumference of the main body 21 and the inner circumference 141 of the side wall, and the emissions generated by the thermal runaway of the electrode assembly 2 may enter the first flow guide channel 7 through the gap. Of course, if the outer circumference of the main body 21 is covered with an insulating film, a gap communicating with the first flow guide gap may be formed between the outer circumference of the insulating film and the inner circumference 141 of the side wall. Among them, the inner circumference 141 of the side wall is the surface of the side wall 14 facing the electrode assembly 2, and the inner circumference may extend along the circumference of the opening of the housing 11 for a whole circumference. It can be understood that if the side wall 14 is cylindrical, the inner circumference 141 of the side wall is cylindrical; if the side wall 14 is rectangular, the inner circumference 141 of the side wall is rectangular.

[0163] The separator 4 may directly abut against the first pole ear 22, or may indirectly abut against the first pole ear 22 through an intermediate member. The intermediate member may be a conductive member or an insulating member. The second flow guide channel 42 on the separator 4 may be one or more. If there are multiple second flow guide channels 42, the multiple second flow guide channels 42 may be evenly distributed along the circumference of the separator 4, or may be unevenly distributed along the circumference of the separator 4. The circumference of the separator 4 may be the circumference of a circle surrounding a center line extending along the first direction Z.

[0164] The second guide channel can be a through hole that penetrates the inner and outer surfaces of the separator 4 only along the radial direction of the separator 4, or it can be a notch groove that penetrates the inner and outer surfaces of the separator 4 along the radial direction of the separator 4 and extends along the first direction Z to the end face of one end of the separator 4.

[0165] In this embodiment, a second guide channel 42 is provided on the separator 4, and the avoidance space 41 and the first guide channel 7 are connected through the second guide channel 42. When the battery cell 10 is in thermal runaway, the emissions located on the side of the electrode assembly 2 flow to the first guide channel 7, and then the emissions can enter the avoidance space 41 through the second guide channel 42 on the separator 4, so that the emissions can quickly reach the vicinity of the pressure relief mechanism 131, so that the pressure relief mechanism 131 can be opened and relieve pressure in time, thereby reducing the risk of explosion and fire of the battery cell 10 and effectively improving the reliability of the battery cell 10.

[0166] In some embodiments, please refer to Figure 9-11 , Fig.11 for Fig.10 The cross-sectional view of the separator 4 shown in FIG. The electrode assembly 2 is formed with a first pole ear 22 at one end close to the first wall portion 13 along the first direction Z, and the separator 4 includes a ring body 43 and a plurality of protrusions 44. Along the first direction Z, the ring body 43 has a first surface 431 and a second surface 432 opposite to each other, and the avoidance space 41 passes through the first surface 431 and the second surface 432. A plurality of protrusions 44 are arranged on the ring body 43 at intervals along the circumferential direction X of the ring body, and the protrusions 44 at least partially protrude from the first surface 431, and a second guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431, and the second guide channel 42 is connected to the avoidance space 41. Among them, along the first direction Z, one of the ring body 43 and the protrusion 44 directly or indirectly abuts against the first pole ear 22, and the first wall portion 13 directly or indirectly abuts against the other of the ring body 43 and the protrusion 44.

[0167] It is understandable that in the embodiment where the first guide channel 7 is formed between the first pole ear 22 and the side wall 14 of the housing 1 , the second guide channel 42 formed between two adjacent protrusions 44 can connect the first guide channel 7 with the avoidance space 41 .

[0168] The ring body 43 is an annular structure, such as a rectangular ring, a circular ring, etc. The avoidance space 41 runs through both ends of the separator 4 along the first direction Z. A part of the avoidance space 41 is located in the ring body 43, and the other part is located in the central area of ​​the multiple protrusions 44. The protrusions 44 in the separator 4 can be two, three, four, five or more. The multiple protrusions 44 can be evenly distributed along the circumferential direction X of the ring body, or unevenly distributed. The circumferential direction X of the ring body is the circumferential direction of the separator 4. A second guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431. The second guide channel 42 of this structure can be a notch groove arranged on the separator 4. In the separator 4, the number of the second guide channels 42 is equal to the number of the protrusions 44. Along the circumferential direction X of the ring body, the second guide channels 42 and the protrusions 44 are alternately arranged.

[0169] The first surface 431 and the second surface 432 may be end surfaces of the ring body 43 at both ends in the thickness direction, and the thickness direction of the ring body 43 is parallel to the first direction Z. The convex portion 44 may be entirely protruded from the first surface 431, so that the convex portion 44 protrudes from the first surface 431 in a direction away from the second surface 432; the convex portion 44 may also be only partially protruded from the first surface 431, for example, the convex portion 44 is connected to the outer peripheral surface 433 or the inner peripheral surface of the ring body, and the convex portion 44 is partially located on the side of the first surface 431 away from the second surface 432, so that a part of the convex portion 44 protrudes from the first surface 431. The convex portion 44 and the ring body 43 may be separately provided and connected, for example, the convex portion 44 and the ring body 43 are bonded or welded, etc.; the convex portion 44 and the ring body 43 may also be integrally formed, so that the convex portion 44 and the ring body 43 are an integrally formed structure.

[0170] The ring body 43 may be directly or indirectly against the first pole ear 22, the first wall portion 13 may be directly or indirectly against the protrusion 44, the first surface 431 faces the first wall portion 13, and the second surface 432 faces the electrode assembly 2, that is, the first surface 431 is farther away from the electrode assembly 2 along the first direction Z than the second surface 432; the protrusion 44 may be directly or indirectly against the first pole ear 22, the first wall portion 13 may be directly or indirectly against the ring body 43, the first surface 431 faces the electrode assembly 2, and the second surface 432 faces the first wall portion 13, that is, the first surface 431 is closer to the electrode assembly 2 along the first direction Z than the second surface 432.

[0171] In this embodiment, since one of the ring body 43 and the protrusion 44 directly or indirectly abuts against the first pole ear 22, and the first wall portion 13 directly or indirectly abuts against the other of the ring body 43 and the protrusion 44, the intermediate piece is supported between the first pole ear 22 and the first wall portion 13, and the intermediate piece can limit the movement of the electrode assembly 2 in the direction close to the first wall portion 13, thereby reducing the risk of the electrode assembly 2 moving in the housing 1 along the first direction Z. Since the second guide channel 42 between two adjacent protrusions 44 is connected to the escape space 41 of the separator 4, when the battery cell 10 is in thermal runaway, the discharge located at the side of the electrode assembly 2 can enter the escape space 41 through the second guide channel 42 between two adjacent protrusions 44, so that the discharge can quickly reach the vicinity of the pressure relief mechanism 131, so that the pressure relief mechanism 131 can release pressure in time, thereby reducing the risk of explosion and fire of the battery cell 10, and effectively improving the reliability of the battery cell 10. That is, the second guide channel 42 and the avoidance space 41 can form a channel for the exhaust to pass through between the electrode assembly 2 and the first wall portion 13 , so that the exhaust located at the side of the electrode assembly 2 can quickly flow to the pressure relief mechanism 131 .

[0172] In some embodiments, the battery cell 10 may include a first current collecting member 5, which is disposed between the separator 4 and the first electrode tab 22 along the first direction Z, the first current collecting member 5 electrically connects the separator 4 and the first electrode tab 22, and the first wall portion 13 electrically connects the separator 4. Along the first direction Z, the protrusion 44 directly abuts against the first current collecting member 5, the first current collecting member 5 directly abuts against the first electrode tab 22, and the first wall portion 13 directly abuts against the ring body 43.

[0173] The first current collecting member 5 and the separator 4 are conductive members disposed between the electrode assembly 2 and the first wall portion 13. The first current collecting member 5 electrically connects the separator 4 and the first pole tab 22, and the first wall portion 13 and the separator 4 are electrically connected, so that the first wall portion 13 and the first pole tab 22 are electrically connected, so that the first wall portion 13 serves as an output pole in the battery cell 10. If the first pole tab 22 is a positive pole tab, the first wall portion 13 is a positive output pole; if the first pole tab 22 is a negative pole sheet, the first wall portion 13 is a negative output pole.

[0174] The convex portion 44 directly abuts against the first current collecting member 5, so that the separator 4 is electrically connected to the first current collecting member 5; the first current collecting member 5 directly abuts against the first pole tab 22, so that the first current collecting member 5 is electrically connected to the first pole tab 22; the first wall portion 13 directly abuts against the ring body 43, so that the first wall portion 13 is electrically connected to the separator 4. It can be understood that in this embodiment, along the first direction Z, the first surface 431 is closer to the electrode assembly 2 than the second surface 432.

[0175] It should be noted that "directly abutting" in the embodiment of the present application means that the two components are in direct contact, and no intermediate piece is provided between the two components. It does not limit the two components to only maintain contact without other connection relationships. In other words, after the two components are directly abutted and in contact, other connection methods can also be used to fix the two components. For example, the protrusion 44 directly abuts against the first current collecting component 5, and the protrusion 44 is welded to the first current collecting component 5; the first current collecting component 5 directly abuts against the first pole ear 22, and the first current collecting component 5 is welded to the first pole ear 22; the first wall portion 13 directly abuts against the ring body 43, and the first wall portion 13 is welded to the ring body 43.

[0176] As an example, Figure 8 As shown, the shell 11 is only opened at one end, and the end cover 12 is the first wall portion 13. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at the two ends of the main body 21. The wall portion of the shell 11 opposite to the end cover 12 is provided with an electrode terminal 3, and the electrode terminal 3 is insulated and connected to the shell 11. The second pole ear 23 of the electrode assembly 2 is electrically connected to the electrode terminal 3 through the second current collecting member 6. The first current collecting member 5 is electrically connected to the separator 4 and the first pole ear 22, and the separator 4 is electrically connected to the first current collecting member 5 and the end cover 12. It can be understood that the electrode terminal 3 is an output pole of the battery cell 10, and the first wall portion 13 is another output pole of the battery cell 10.

[0177] In this embodiment, the electrical connection between the first pole tab 22 and the separator 4 can be achieved by arranging the first current collecting member 5 between the separator 4 and the first pole tab 22, thereby reducing the difficulty of the electrical connection between the first pole tab 22 and the separator 4. The convex portion 44 directly abuts against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43, so that the second guide channel 42 is formed on the side of the separator 4 facing the electrode assembly 2, so that the discharge located on the side of the electrode assembly 2 when the battery cell 10 thermally runs away can enter the second guide channel 42 more quickly.

[0178] In some embodiments, please refer to Fig.12 , Fig.12 for Fig.11 The A-direction view of the partition 4 is shown. The ring body 43 and the first wall portion 13 ( Fig. 9 ) is welded to form a first weld zone 45, at least one convex portion 44 is welded to the first current collecting member 5 ( Fig. 9 (shown in FIG. 4 ) welding forms a second weld print area 46, and along the first direction Z, the projection of the first weld print area 45 does not overlap with the projection of the second weld print area 46.

[0179] The first weld mark area 45 is an area where the ring body 43 and the first wall portion 13 are welded to form a weld mark, and the first weld mark area 45 may be a portion where the ring body 43 and the first wall portion 13 are welded and fused together. The first weld mark area 45 may be one or more.

[0180] The second weld mark area 46 is an area where the protrusion 44 and the first current collecting member 5 are welded to form a weld mark. The second weld mark area 46 may be a portion where the protrusion 44 and the first current collecting member 5 are welded and fused together. One protrusion 44 may be welded to the first current collecting member 5 to form one second weld mark area 46, or multiple protrusions 44 may be welded to the first current collecting member 5 to form multiple second weld marks areas 46.

[0181] The projection of the first weld print area 45 along the first direction Z may be located at a position of the separator 4 corresponding to the second guide channel 42 , and the projection of the first weld print area 45 along the first direction Z may be located at a position of the separator 4 corresponding to the protrusion 44 .

[0182] As an example, Fig.12 As shown, there are multiple first weld areas 45 and second weld areas 46, which are alternately arranged along the circumferential direction X of the ring body. The projection of the first weld area 45 along the first direction Z is located at a position corresponding to the separator 4 and the second guide channel 42.

[0183] In this embodiment, the projection of the first weld print area 45 along the first direction Z does not overlap with the projection of the second weld print area 46 along the first direction Z, which can reduce the mutual interference between the first weld print area 45 and the second weld print area 46, and reduce the risk of cold welding when the ring body 43 is welded to the first wall portion 13 or the protrusion 44 is welded to the first current collecting member 5.

[0184] In some embodiments, please refer to Fig.10 and Fig.11 The protrusion 44 includes a first portion 441, the first portion 441 includes a first bending portion 4411 and a first connecting portion 4412, the first bending portion 4411 is connected to the outer peripheral surface 433 of the ring body, the first connecting portion 4412 is connected to the first bending portion 4411, and the first connecting portion 4412 is at least partially located on the side of the first surface 431 away from the second surface 432.

[0185] The convex portion 44 may include only the first portion 441, or may include other portions in addition to the first portion 441. The outer peripheral surface 433 of the ring body connects the first surface 431 and the second surface 432. The first connecting portion 4412 is at least partially located on the side of the first surface 431 away from the second surface 432, so that the first surface 431 is located between at least a portion of the first connecting portion 4412 and the second surface 432 along the first direction Z. The first connecting portion 4412 may be completely located on the side of the first surface 431 away from the second surface 432, so that the first connecting portion 4412 and the ring body 43 are arranged along the first direction Z; the first connecting portion 4412 may also be only partially located on the side of the first surface 431 away from the second surface 432. Along the first direction Z, the first connecting portion 4412 and the first surface 431 may be in contact, or there may be a gap.

[0186] The first connection portion 4412 may be a single-layer structure or a multi-layer structure formed by at least one bending. Fig.10 In the illustrated embodiment, the first connection portion 4412 is a single-layer structure.

[0187] The first bending portion 4411 may be provided with a process notch to reduce the force required when bending the first bending portion 4411 .

[0188] In this embodiment, the first portion 441 is a structure connected to the outer peripheral surface 433 of the ring body and partially bent on the side of the first surface 431 away from the second surface 432. The structure of the first portion 441 is simple, thereby reducing the difficulty of forming the convex portion 44. In addition, since the first bent portion 4411 is connected to the outer peripheral surface 433 of the ring body, the first bent portion 4411 does not occupy the internal space of the ring body 43, which can increase the avoidance space 41, improve the avoidance ability of the avoidance space 41 to the pressure relief mechanism 131 and the diversion ability for the discharge flow.

[0189] In some embodiments, please refer to Fig.10 and Fig.11 , along the first direction Z, a gap is set between the first connection portion 4412 and the first surface 431 .

[0190] A first gap 4413 is formed between the first connection portion 4412 and the first surface 431 , such that the first connection portion 4412 is not in contact with the first surface 431 .

[0191] In this embodiment, the first connection portion 4412 and the first surface 431 are arranged with a gap along the first direction Z, and the separator 4 can play a buffering role between the first wall portion 13 and the electrode assembly 2 to absorb the impact force on the first wall portion 13, thereby reducing the risk of the electrode assembly 2 being damaged by the external impact on the first wall portion 13. In addition, a first gap 4413 can be formed between the first connection portion 4412 and the first surface 431 to connect two adjacent second guide channels 42. When the emissions located at the side of the electrode assembly 2 flow toward one of the second guide channels 42, the emissions can flow toward another adjacent second guide channel 42 through the first gap 4413, so that the emissions can enter the avoidance space 41 more quickly.

[0192] In some embodiments, please refer to Figure 13-Figure 16 , Fig.13 A partial view of a battery cell 10 (the protrusion 44 includes a first portion 441 , and the first portion 441 is connected to the outer peripheral surface 433 of the ring body) provided in some embodiments of the present application; Fig.14 for Fig.13 An axonometric view of the separator 4 shown; Fig.15 Partial views of battery cells 10 (the protrusion 44 includes a first portion 441 , and the first portion 441 is connected to the outer peripheral surface 433 of the ring body) provided in other embodiments of the present application; Fig.16 for Fig.15 The first connecting portion 4412 includes a second bending portion 44121 and a plurality of first stacking portions 44122 . The plurality of first stacking portions 44122 are located on a side of the first surface 431 away from the second surface 432 . The plurality of first stacking portions 44122 are arranged along the first direction Z. The second bending portion 44121 connects two adjacent first stacking portions 44122 .

[0193] The first stacking parts 44122 in the first connecting part 4412 can be two, three, four, five or more. Two adjacent first stacking parts 44122 can be in direct contact or there can be a gap. Two adjacent first stacking parts 44122 are connected by a second bending part 44121. In the first connecting part 4412, there is one more first stacking part 44122 than the second bending part 44121. The first bending part 4411 can be connected to any one of the first stacking parts 44122, and can also be connected to any one of the first bending parts 4411. Since the first connecting part 4412 includes multiple first stacking parts 44122, the first connecting part 4412 is a multi-layer structure.

[0194] The first portion 441 may be made of metal or insulating material. In the embodiment where the convex portion 44 only includes the first portion 441 and the convex portion 44 directly abuts against the first current collecting member 5, the first portion 441 may be made of metal, and may be a first laminated portion 44122 of the first connecting portion 4412 that is farthest from the ring body 43 abuts against the first current collecting member 5 to achieve electrical connection between the separator 4 and the first current collecting member 5.

[0195] The second bending portion 44121 may be provided with a process notch to reduce the force required when bending the second bending portion 44121 .

[0196] In this embodiment, there are multiple first stacked portions 44122 in the first connecting portion 4412, and the multiple first stacked portions 44122 are arranged along the first direction Z on the side of the first surface 431 away from the second surface 432, and two adjacent first stacked portions 44122 are connected by the second bending portion 44121. This structure can increase the height of the protrusion 44 protruding from the first surface 431, thereby increasing the size of the second guide channel 42 in the first direction Z, thereby improving the smoothness of the flow of emissions in the second guide channel 42.

[0197] In some embodiments, please refer to Fig.14 and Fig.16 , along the first direction Z, two adjacent first stacking parts 44122 are arranged with a gap.

[0198] Two adjacent first stacking portions 44122 are spaced apart along the first direction Z, and a second gap 4414 is formed between the two adjacent first stacking portions 44122 so that the two connected first stacking portions 44122 are not in contact with each other.

[0199] In this embodiment, two adjacent first stacking parts 44122 are arranged with a gap along the first direction Z, so that a second gap 4414 can be formed between the two adjacent first stacking parts 44122, so that the first connecting part 4412 can play a buffering role between the first wall part 13 and the electrode assembly 2 to absorb the impact force on the first wall part 13, and reduce the risk of the first wall part 13 being damaged by external impact and causing the electrode assembly 2. In addition, the second gap 4414 formed between the two adjacent first stacking parts 44122 can connect the two adjacent second guide channels 42. When the emissions located at the side of the electrode assembly 2 flow to a certain second guide channel 42, the emissions can flow to another adjacent second guide channel 42 through the second gap 4414, so that the emissions can enter the avoidance space 41 more quickly.

[0200] In some embodiments, please refer to Fig.14, along the first direction Z, a first stacking portion 44122 closest to the first surface 431 is connected to the first bending portion 4411 .

[0201] As an example, there are two first stacking portions 44122 in the first connecting portion 4412, and one second bending portion 44121, and the first bending portion 4411, a first stacking portion 44122 close to the ring body 43, the second bending portion 44121 and a first stacking portion 44122 away from the ring body 43 are connected in sequence.

[0202] In some embodiments, please refer to Fig.16 , along the first direction Z, a first stacking portion 44122 farthest from the first surface 431 is connected to the first bending portion 4411 .

[0203] As an example, there are two first stacking portions 44122 in the first connecting portion 4412, and one second bending portion 44121, and the first bending portion 4411, a first stacking portion 44122 away from the ring body 43, the second bending portion 44121 and a first stacking portion 44122 close to the ring body 43 are arranged in sequence.

[0204] In some embodiments, please refer to Fig.14 and Fig.16 The first portion 441 is formed by integrally bending a plate.

[0205] In this embodiment, the first portion 441 and the ring body 43 can be integrally formed; the first portion 441 and the ring body 43 can also be separately provided and connected, such as by welding. The first connecting portion 4412 and the first bending portion 4411 can be formed by bending the plate integrally, and the first connecting portion 4412 can form a plurality of first stacking portions 44122 after being bent multiple times.

[0206] In this embodiment, the first portion 441 is formed by integrally bending a plate. The first portion 441 of this structure has high structural stability and low molding difficulty.

[0207] In some embodiments, please refer to Figure 17-Figure 20 , Fig.17 A partial view of a battery cell 10 (the protrusion 44 includes a first portion 441 and a second portion 442 , the first portion 441 is connected to the outer circumferential surface 433 of the ring body, and the second portion 442 is connected to the inner circumferential surface 434 of the ring body) provided in some embodiments of the present application; Fig.18 for Fig.17 An axonometric view of the separator 4 shown; Fig.19A partial view of a battery cell 10 (the protrusion 44 includes a first portion 441 and a second portion 442 , the first portion 441 is connected to the outer circumferential surface 433 of the ring body, and the second portion 442 is connected to the inner circumferential surface 434 of the ring body) provided in some other embodiments of the present application; Fig. 20 for Fig.19 The isometric view of the separator 4 is shown. The convex portion 44 includes a second portion 442, the second portion 442 includes a third bent portion 4421 and a second connecting portion 4422, the third bent portion 4421 is connected to the inner circumferential surface 434 of the ring body, the second connecting portion 4422 is connected to the third bent portion 4421, the second connecting portion 4422 is at least partially located on the side of the first surface 431 away from the second surface 432, and the second connecting portion 4422 and the first connecting portion 4412 are arranged along the first direction Z. The first connecting portion 4412 is closer to the first surface 431 along the first direction Z than the second connecting portion 4422; or, the second connecting portion 4422 is closer to the first surface 431 along the first direction Z than the first connecting portion 4412.

[0208] In this embodiment, the convex portion 44 includes a first portion 441 and a second portion 442. The first portion 441 is connected to the outer circumference 433 of the ring body, and the second portion 442 is connected to the inner circumference 434 of the ring body. The first connecting portion 4412 can be a single-layer structure or a multi-layer structure formed by at least one bending; the first connecting portion 4412 can be a single-layer structure or a multi-layer structure formed by at least one bending.

[0209] exist Fig.17 and Fig.18 In the illustrated embodiment, both the first connection portion 4412 and the second connection portion 4422 are single-layer structures, and the first connection portion 4412 is closer to the first surface 431 than the second connection portion 4422, that is, the first connection portion 4412 is located between the second connection portion 4422 and the ring body 43. The second connection portion 4422 directly abuts against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0210] exist Fig.19 and Fig. 20 In the illustrated embodiment, both the first connection portion 4412 and the second connection portion 4422 are single-layer structures, and the second connection portion 4422 is closer to the first surface 431 along the first direction Z than the first connection portion 4412, that is, the second connection portion 4422 is located between the first connection portion 4412 and the ring body 43. The first connection portion 4412 directly abuts against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0211] In this embodiment, the second connection portion 4422 of the second part 442 and the first connection portion 4412 of the first part 441 are arranged along the first direction Z, which can increase the height of the protrusion 44 protruding from the first surface 431, thereby increasing the size of the second guide channel 42 in the first direction Z, thereby improving the smoothness of the flow of emissions in the second guide channel 42.

[0212] In some embodiments, please refer to Fig.21 and Fig. 22 , Fig.21 A partial view of a battery cell 10 (a first portion 441 is connected to an inner circumferential surface 434 of the ring body) provided in some embodiments of the present application; Fig. 22 for Fig.21 The isometric view of the separator 4 is shown. The protrusion 44 includes a second portion 442, and the second portion 442 includes a third bent portion 4421 and a second connecting portion 4422, the third bent portion 4421 is connected to the inner circumferential surface 434 of the ring body, and the second connecting portion 4422 is connected to the third bent portion 4421, and the second connecting portion 4422 is at least partially located on the side of the first surface 431 away from the second surface 432.

[0213] The convex portion 44 may include only the second portion 442, or may include other portions in addition to the second portion 442. For example, the convex portion 44 also includes the first portion 441 in the aforementioned embodiment. The inner circumferential surface 434 of the ring body connects the first surface 431 and the second surface 432. The second connecting portion 4422 is at least partially located on the side of the first surface 431 away from the second surface 432, so that the first surface 431 is located between at least a portion of the second connecting portion 4422 and the second surface 432 along the first direction Z. The second connecting portion 4422 may be completely located on the side of the first surface 431 away from the second surface 432, so that the second connecting portion 4422 and the ring body 43 are arranged along the first direction Z; the second connecting portion 4422 may also be only partially located on the side of the first surface 431 away from the second surface 432. Along the first direction Z, the second connecting portion 4422 may be in contact with the first surface 431, or there may be a gap.

[0214] The second connection portion 4422 may be a single-layer structure or a multi-layer structure formed by at least one bending. Fig.21 and Fig. 22 In the illustrated embodiment, the second connection portion 4422 is a single-layer structure.

[0215] The third bending portion 4421 may be provided with a process notch to reduce the force required when bending the third bending portion 4421 .

[0216] In this embodiment, the second portion 442 is a structure connected to the inner circumferential surface 434 of the ring body and partially bent at the side of the first surface 431 away from the second surface 432. The structure of the second portion 442 is simple, thereby reducing the difficulty of forming the convex portion 44. In addition, since the third bent portion 4421 is connected to the inner circumferential surface 434 of the ring body, the size of the third bent portion 4421 along the circumferential direction X of the ring body can be reduced, and the material used for the third bent portion 4421 can be reduced.

[0217] In some embodiments, along the first direction Z, the second connection portion 4422 and the first surface 431 are spaced apart.

[0218] A third gap 4423 is formed between the second connection portion 4422 and the first surface 431 , so that the second connection portion 4422 does not contact the first surface 431 .

[0219] In this embodiment, the second connection portion 4422 and the first surface 431 are arranged with a gap along the first direction Z, and the separator 4 can play a buffering role between the first wall portion 13 and the electrode assembly 2 to absorb the impact force on the first wall portion 13, thereby reducing the risk of the electrode assembly 2 being damaged by the external impact on the first wall portion 13. In addition, a third gap 4423 can be formed between the second connection portion 4422 and the first surface 431 to connect two adjacent second guide channels 42. When the emissions located at the side of the electrode assembly 2 flow toward one of the second guide channels 42, the emissions can flow toward another adjacent second guide channel 42 through the third gap 4423, so that the emissions can enter the avoidance space 41 more quickly.

[0220] In some embodiments, please refer to Figure 23-Figure 26 , Fig.23 Partial views of battery cells 10 (the protrusion 44 includes a second portion 442 , and the second portion 442 is connected to the inner circumferential surface 434 of the ring body) provided in other embodiments of the present application; Fig.24 for Fig.23 An axonometric view of the separator 4 shown; Fig.25 A partial view of a battery cell 10 (the protrusion 44 includes a second portion 442 , and the second portion 442 is connected to the inner circumferential surface 434 of the ring body) provided in some other embodiments of the present application; Fig.26 for Fig.25 The second connecting portion 4422 includes a fourth bending portion 44221 and a plurality of second stacking portions 44222 , the plurality of second stacking portions 44222 are located on a side of the first surface 431 away from the second surface 432 , and the plurality of second stacking portions 44222 are arranged along the first direction Z. The fourth bending portion 44221 connects two adjacent second stacking portions 44222 .

[0221] The second laminated parts 44222 in the second connecting part 4422 can be two, three, four, five or more. Two adjacent second laminated parts 44222 can be in direct contact or there can be a gap. Two adjacent second laminated parts 44222 are connected by a fourth bending part 44221. In the second connecting part 4422, there is one more second laminated part 44222 than the fourth bending part 44221. The third bending part 4421 can be connected to any one of the second laminated parts 44222, and can also be connected to any one of the fourth bending parts 44221. Since the second connecting part 4422 includes a plurality of second laminated parts 44222, the second connecting part 4422 is a multilayer structure.

[0222] The second portion 442 may be made of metal or insulating material. In the embodiment where the convex portion 44 only includes the second portion 442 and the convex portion 44 directly abuts against the first current collecting member 5, the second portion 442 may be made of metal, and may be a second laminated portion 44222 of the second connecting portion 4422 that is farthest from the ring body 43 abuts against the first current collecting member 5 to achieve electrical connection between the separator 4 and the first current collecting member 5.

[0223] The fourth bending portion 44221 may be provided with a process notch to reduce the force required when bending the fourth bending portion 44221 .

[0224] In this embodiment, there are multiple second stacked portions 44222 in the second connecting portion 4422, and the multiple second stacked portions 44222 are arranged along the first direction Z on the side of the first surface 431 away from the second surface 432, and two adjacent second stacked portions 44222 are connected by a fourth bending portion 44221. This structure can increase the height of the protrusion 44 protruding from the first surface 431, thereby increasing the size of the second guide channel 42 in the first direction Z, thereby improving the smoothness of the flow of emissions in the second guide channel 42.

[0225] In some embodiments, please refer to Fig.24 and Fig.26 , along the first direction Z, two adjacent second stacking parts 44222 are arranged with a gap.

[0226] Two adjacent second stacking portions 44222 are spaced apart along the first direction Z, and a fourth gap 4424 is formed between the two adjacent second stacking portions 44222 , so that the two connected second stacking portions 44222 are not in contact with each other.

[0227] In this embodiment, two adjacent second laminated parts 44222 are arranged with a gap along the first direction Z, so that a fourth gap 4424 can be formed between the two adjacent second laminated parts 44222, so that the second connecting part 4422 can play a buffering role between the first wall part 13 and the electrode assembly 2 to absorb the impact force on the first wall part 13, and reduce the risk of the first wall part 13 being damaged by external impact and causing the electrode assembly 2. In addition, the fourth gap 4424 formed between the two adjacent second laminated parts 44222 can connect the two adjacent second guide channels 42. When the emissions located at the side of the electrode assembly 2 flow to a certain second guide channel 42, the emissions can flow to another adjacent second guide channel 42 through the fourth gap 4424, so that the emissions can enter the avoidance space 41 more quickly.

[0228] In some embodiments, please refer to Fig.24 , along the first direction Z, a second stacking portion 44222 closest to the first surface 431 is connected to the third bending portion 4421 .

[0229] As an example, there are two second stacked portions 44222 in the second connecting portion 4422, there is one fourth bending portion 44221, and the third bending portion 4421, a second stacked portion 44222 close to the ring body 43, the fourth bending portion 44221 and a second stacked portion 44222 away from the ring body 43 are connected in sequence.

[0230] In some embodiments, please refer to Fig.26 , along the first direction Z, a second stacking portion 44222 farthest from the first surface 431 is connected to the third bending portion 4421 .

[0231] As an example, there are two second stacked portions 44222 in the second connecting portion 4422, there is one fourth bending portion 44221, and the third bending portion 4421, a second stacked portion 44222 away from the ring body 43, the fourth bending portion 44221 and a second stacked portion 44222 close to the ring body 43 are arranged in sequence.

[0232] In some embodiments, the second portion 442 is formed by bending a plate in one piece.

[0233] In this embodiment, the second portion 442 and the ring body 43 can be integrally formed; the second portion 442 and the ring body 43 can also be separately provided and connected, such as by welding. The second connecting portion 4422 and the third bending portion 4421 can be formed by bending the plate integrally, and the second connecting portion 4422 can form a plurality of second stacking portions 44222 after being bent multiple times.

[0234] In this embodiment, the second portion 442 is formed by integrally bending a plate material. The second portion 442 of this structure has high structural stability and low molding difficulty.

[0235] In some embodiments, please refer to Fig.25 , along the first direction Z, the minimum thickness of the ring body 43 is D, D≥0.3mm.

[0236] The thickness of the ring body 43 is the minimum distance between the first surface 431 and the second surface 432 .

[0237] D can be any point value among 0.3mm, 0.5mm, 0.8mm, 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, 2.3mm, 2.5mm, 2.8mm, 3mm, 3.3mm, 3.5mm, 3.8mm, 4mm, 4.3mm, 4.5mm, 4.8mm, 5mm, or a range value between any two of them.

[0238] In this embodiment, D≥0.3mm, so that the ring body 43 has a sufficient thickness. On the one hand, the ring body 43 has sufficient structural strength. On the other hand, there is a sufficiently large distance between the electrode assembly 2 and the first wall portion 13, thereby further reducing the risk of damage to the pressure relief mechanism 131 caused by the electrode assembly 2 directly impacting the pressure relief mechanism 131 when the electrode assembly 2 expands and deforms or the first wall portion 13 is deformed by external force.

[0239] In some embodiments, please refer to Fig.25 and Fig.26 The separator 4 electrically connects the first wall portion 13 and the first electrode ear 22. Along the circumferential direction X of the ring body, the sum of the maximum dimensions of all protrusions 44 is A1, and the sum of the maximum dimensions of all second guide channels 42 is A2, 0.1≤A1 / (A1+A2)≤0.8.

[0240] The separator 4 and the first wall portion 13 may be directly connected or indirectly connected to achieve electrical connection between the separator 4 and the first wall portion 13. The separator 4 and the first electrode tab 22 may be directly connected or indirectly connected to achieve electrical connection between the separator 4 and the first electrode tab 22.

[0241] Along the circumferential direction X of the ring body, the maximum sizes of the protrusions 44 may be equal or unequal, and the maximum sizes of the second flow guiding channels 42 may be equal or partial.

[0242] As an example, the ring body 43 is a circular ring structure, and along the circumferential direction X of the ring body, the convex portion 44 extends along an arc trajectory, and the maximum size of all convex portions 44 is equal, the maximum size of the convex portion 44 is the maximum arc length of the convex portion 44, and the maximum size of the second guide channel 42 is the maximum arc length of the second guide channel 42. The maximum size of the convex portion 44 is a1, the maximum size of the second guide channel 42 is a2, the number of the convex portions 44 and the number of the second guide channel 42 are both n, A1 = a1 × n, A2 = a2 × n, A1 / (A1+A2) = a1 / (a1+a2).

[0243] A1 / (A1+A2) can take any point value among 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8 or a range of values ​​between any two of them.

[0244] A1 / (A1+A2)≥0.1, so that the size of all protrusions 44 in the circumferential direction X of the ring body is not too small, so that all protrusions 44 as a whole and the components they directly abut against have sufficient contact area to achieve stable flow; A1 / (A1+A2)≤0.8, so that the size of all second guide channels 42 in the circumferential direction X of the ring body is not too small, so that the discharge from the side of the electrode assembly 2 can quickly enter the avoidance space 41, so that the pressure relief mechanism 131 can open and relieve pressure more timely.

[0245] In some embodiments, the separator 4 electrically connects the first wall portion 13 and the electrode assembly 2 .

[0246] It is understandable that the separator 4 is a conductive member. The separator 4 may abut against the first wall portion 13 directly or indirectly to achieve electrical connection between the separator 4 and the first wall portion 13. The separator 4 may abut against the electrode assembly 2 directly or indirectly to achieve electrical connection between the separator 4 and the electrode assembly 2.

[0247] In this embodiment, the separator 4 not only serves to separate the first wall portion 13 and the electrode assembly 2 , but also serves to electrically connect the first wall portion 13 and the electrode assembly 2 .

[0248] In some embodiments, the battery cell 10 includes a first current collecting member 5, which is disposed between the separator 4 and the electrode assembly 2 along the first direction Z. The first current collecting member 5 electrically connects the separator 4 and the electrode assembly 2. Along the first direction Z, the projection of the first current collecting member 5 covers the avoidance space 41.

[0249] It can be understood that the electrode assembly 2 is electrically connected to the first wall portion 13 via the first current collecting member 5 and the separator 4 , and both the first current collecting member 5 and the separator 4 are conductive members.

[0250] In this embodiment, the escape space 41 may be a through hole penetrating two opposite ends of the partition 4 along the first direction Z, or may be an escape groove provided on a side of the partition 4 facing the first wall portion 13 .

[0251] In an embodiment where the avoidance space 41 runs through both ends of the partition 4 along the first direction Z, and the partition 4 directly abuts against the first current collecting component 5, along the first direction Z, the projection of the first current collecting component 5 covers the avoidance space 41, so that the first current collecting component 5 covers one end of the avoidance space 41.

[0252] In an embodiment where the partition 4 includes a ring body 43 and a protrusion 44, the first wall portion 13 may directly abut against the ring body 43, and the protrusion 44 may directly abut against the first current collecting member 5, so that the second guide channel 42 faces the first current collecting member 5; or the first wall portion 13 may directly abut against the protrusion 44, and the ring body 43 may directly abut against the first current collecting member 5, so that the second guide channel 42 faces the first wall portion 13.

[0253] In the present embodiment, the first current collecting member 5 is provided between the separator 4 and the electrode assembly 2 to achieve electrical connection between the electrode assembly 2 and the separator 4 , thereby reducing the difficulty of electrical connection between the electrode assembly 2 and the separator 4 .

[0254] In some embodiments, the separator 4 is welded to the first wall portion 13 to form a first weld zone 45 , and the separator 4 is welded to the first current collecting member 5 to form a second weld zone 46 . Along the first direction Z, the projection of the first weld zone 45 does not overlap with the projection of the second weld zone 46 .

[0255] The first weld mark area 45 is an area where a weld mark is formed by welding the separator 4 and the first wall portion 13. The first weld mark area 45 may be a portion where the separator 4 and the first wall portion 13 are welded and fused together. The first weld mark area 45 may be one or more.

[0256] The second weld print area 46 is an area where the separator 4 and the first current collecting member 5 are welded to form a weld print. The second weld print area 46 may be a portion where the separator 4 and the first current collecting member 5 are welded and fused together. The first weld print area 45 may be one or more. The number of first weld print areas 45 and the number of second weld print areas 46 may be equal or different. The projection of the first weld print area 45 along the first direction Z and the projection of the second weld print area 46 along the first direction Z may be arranged at intervals along the circumference of the separator 4 to achieve that the projection of the first weld print area 45 and the projection of the second weld print area 46 do not overlap. Taking the example that the number of the first weld print area 45 is equal to the number of the second weld print area 46, the first weld print area 45 and the second weld print area 46 may be arranged alternately along the circumference of the separator 4.

[0257] In the embodiment where the separator 4 includes the ring body 43 and the protrusion 44, the ring body 43 may be welded to the first wall portion 13 to form the first weld print area 45, and the protrusion 44 may be welded to the first current collecting member 5 to form the second weld print area 46; or the protrusion 44 may be welded to the first wall portion 13 to form the first weld print area 45, and the ring body 43 may be welded to the first current collecting member 5 to form the second weld print area 46.

[0258] As an example, the first current collecting member 5 is welded to the first electrode tab 22 of the electrode assembly 2 , and the first wall portion 13 , the separator 4 , the first current collecting member 5 and the first electrode tab 22 are made of the same material.

[0259] In this embodiment, the projection of the first weld print area 45 along the first direction Z does not overlap with the projection of the second weld print area 46 along the first direction Z, which can reduce the mutual interference between the first weld print area 45 and the second weld print area 46, and reduce the risk of cold welding when the separator 4 is welded to the first wall portion 13 or the separator 4 is welded to the first current collecting member 5.

[0260] In some embodiments, the electrode assembly 2 is formed with a first pole tab 22 at one end close to the first wall portion 13 along the first direction Z, and the material of the first pole tab 22 is different from the material of the first wall portion 13. The material of the first current collecting member 5 is the same as that of the first pole tab 22, and the first current collecting member 5 is welded to the first pole tab 22. The material of the separator 4 is the same as that of the first wall portion 13, and the separator 4 is welded to the first wall portion 13. The first current collecting member 5 is compositely connected to the separator 4.

[0261] The first pole tab 22 may be made of copper, iron, aluminum, steel, aluminum alloy, etc., and the first wall portion 13 may be made of copper, iron, aluminum, steel, aluminum alloy, etc. The first current collecting member 5 and the separator 4 may be compositely connected by hot pressing, cold pressing, friction welding, etc., so as to fix the first current collecting member 5 and the separator 4.

[0262] As an example, the first electrode tab 22 is a negative electrode tab, the first electrode tab 22 and the first current collecting member 5 are made of copper, and the first wall portion 13 and the separator 4 are made of aluminum.

[0263] As an example, the first electrode tab 22 is a negative electrode tab, the first electrode tab 22 and the first current collecting member 5 are made of copper, and the first wall portion 13 and the separator 4 are made of steel.

[0264] In this embodiment, the material of the first current collecting component 5 is the same as that of the first pole ear 22, which can reduce the difficulty of welding the first current collecting component 5 and the first pole ear 22, improve the firmness of the first current collecting component 5 and the first pole ear 22 after welding, and achieve stable flow between the first current collecting component 5 and the first pole ear 22; the material of the separator 4 is the same as that of the first wall portion 13, which can reduce the difficulty of welding the separator 4 and the first wall portion 13, improve the firmness of the separator 4 and the first wall portion 13 after welding, and achieve stable flow between the separator 4 and the first wall portion 13; the first current collecting component 5 and the separator 4 are compositely connected, which achieves stable flow between the first current collecting component 5 and the separator 4, and then achieves stable flow between the first wall portion 13 and the first pole ear 22.

[0265] In some embodiments, the electrode assembly 2 is provided with a first central hole 24 , and the first current collecting member 5 is provided with a second central hole 51 , and the second central hole 51 communicates with the first central hole 24 and the avoidance space 41 .

[0266] The escape space 41 may pass through both ends of the partition 4 along the first direction Z, so that the second center hole 51 can communicate with the first center hole 24 and the escape space 41 .

[0267] As an example, the electrode assembly 2 is a winding structure, and the first center hole 24 is located at the winding center of the winding structure. The first center hole 24 and the second center hole 51 are both cylindrical holes, the first center hole 24 and the second center hole 51 are coaxially arranged, and the aperture of the first center hole 24 is larger than the aperture of the second center hole 51.

[0268] When the battery cell 10 is in thermal runaway, the emissions generated by the electrode assembly 2 can enter the escape space 41 through the first center hole 24 and the second center hole 51 in sequence, so that the pressure relief mechanism 131 can be opened and relieve pressure more timely.

[0269] In some embodiments, please refer to Fig. 27 and Fig.28 , Fig. 27 A schematic diagram of the structure of the first wall portion 13 provided in some embodiments of the present application; Fig.28 for Fig. 27 1 is a cross-sectional view of the first wall portion 13. The first wall portion 13 includes a wall body 132 and abutment portion 133. The wall body 132 is provided with a pressure relief mechanism 131. The abutment portion 133 is arranged around the outer edge of the wall body 132. Along the first direction Z, the abutment portion 133 protrudes from the wall body 132 in a direction close to the electrode assembly 2, and directly or indirectly abuts against the separator 4.

[0270] The end cover 12 may be used as the first wall portion 13, or the wall portion of the housing 11 opposite to the end cover 12 may be used as the first wall portion 13. The wall body 132 and the abutment portion 133 may be integrally formed, or they may be separately provided and connected. The pressure relief mechanism 131 may be a pressure relief member separately provided from the wall body 132, or the pressure relief mechanism 131 may be a structure integrally formed with the wall body 132.

[0271] The abutting portion 133 may be an annular structure surrounding the outer edge of the wall body 132. After the abutting portion 133 directly or indirectly abuts against the separator 4, the abutting portion 133 and the electrode assembly 2 may be electrically connected or insulated. As an example, the abutting portion 133 directly abuts against the separator 4 to achieve electrical connection between the first wall portion 13 and the separator 4.

[0272] The wall body 132 and the abutment portion 133 may jointly define a flow guiding space 134, and the flow guiding space 134 is arranged corresponding to the avoidance space 41, and the flow guiding space 134 is connected to the avoidance space 41. After the pressure relief mechanism 131 is opened, the exhaust entering the avoidance space 41 may flow to the pressure relief mechanism 131 through the flow guiding space 134, and finally be discharged to the outside of the battery cell 10 through the pressure relief mechanism 131.

[0273] In this embodiment, the abutment portion 133 protrudes from the wall body 132 in a direction close to the electrode assembly 2, and directly or indirectly abuts against the separator 4, which can increase the distance between the pressure relief mechanism 131 and the separator 4, thereby further reducing the influence of the separator 4 on the pressure relief mechanism 131, and further reducing the risk of damage to the pressure relief mechanism 131 caused by the separator 4 directly impacting the pressure relief mechanism 131 when the electrode assembly 2 expands and deforms or the first wall portion 13 is deformed by external force.

[0274] In some embodiments, please refer to Fig.25 The housing 1 includes a side wall 14 that is separate from the first wall portion 13 . The side wall 14 is disposed around the first wall portion 13 . The first wall portion 13 is disposed at one end of the side wall 14 along the first direction Z. At least a portion of the abutting portion 133 is accommodated in the side wall 14 and forms a positioning fit with the side wall 14 .

[0275] The first wall portion 13 and the side wall 14 are arranged separately, that is, the first wall portion 13 and the side wall 14 are two parts that are not formed in one piece. As an example, the first wall portion 13 is the end cover 12 in the housing 1, and the first wall portion 13 and the side wall 14 are welded together.

[0276] The portion of the abutment portion 133 received in the side wall 14 forms a positioning fit with the side wall 14, so that the outer circumference of the abutment portion 133 is in contact with the inner circumference 141 of the side wall. As an example, the portion of the abutment portion 133 received in the side wall 14 forms an interference fit with the side wall 14.

[0277] As an example, the first wall portion 13 may further include an edge portion 135 ( Fig. 27 and Fig.28 As shown in FIG. 1 , the edge portion 135 is disposed around the outer edge of the abutting portion 133 , and the edge portion 135 abuts against one end of the side wall 14 to limit the first wall portion 13 from moving relative to the side wall 14 toward the direction close to the electrode assembly 2 .

[0278] In this embodiment, the first wall portion 13 and the side wall 14 are separately provided, so as to facilitate the installation of the electrode assembly 2 into the housing 1. The positioning cooperation between the abutting portion 133 and the side wall 14 can effectively improve the assembly difficulty of the first wall portion 13 and the side wall 14. Taking the welding of the first wall portion 13 and the side wall 14 as an example, the positioning cooperation between the abutting portion 133 and the side wall 14 can effectively reduce the risk of radial displacement of the first wall portion 13 relative to the side wall 14 during welding, thereby reducing the welding difficulty.

[0279] In some embodiments, please refer to Fig. 27 and Fig.28 The pressure relief mechanism 131 is integrally formed with the first wall portion 13 .

[0280] In this embodiment, the pressure relief mechanism 131 is integrally formed with the first wall portion 13 to form an integrated pressure relief mechanism 131 . The pressure relief mechanism 131 has higher reliability, eliminates the installation process of the pressure relief mechanism 131 , and has better economy.

[0281] In some other embodiments, the pressure relief mechanism 131 and the first wall portion 13 are provided separately, and the pressure relief mechanism 131 is installed on the first wall portion 13 .

[0282] The first wall portion 13 may be provided with a pressure relief hole, and the pressure relief mechanism 131 covers the pressure relief hole.

[0283] In this embodiment, the pressure relief mechanism 131 is separately arranged from the first wall portion 13, and the pressure relief mechanism 131 is installed on the first wall portion 13, so that the pressure relief mechanism 131 is a component independent of the outer shell 1. The pressure relief mechanism 131 and the outer shell 1 can be produced and assembled separately, with low production difficulty and high efficiency.

[0284] In some embodiments, please refer to Fig. 27 and Fig.28 The pressure relief mechanism 131 includes a weak portion 1311 and a pressure relief area 1312 , and the weak portion 1311 is arranged along the edge of the pressure relief area 1312 .

[0285] As an example, the pressure relief mechanism 131 is provided with a pressure relief groove 136 to form a weak portion 1311 at a position of the pressure relief mechanism 131 corresponding to the pressure relief groove 136. The bottom wall of the pressure relief groove 136 may be the weak portion 1311, and the bottom wall of the pressure relief groove 136 is the portion of the first wall portion 13 located at the bottom of the pressure relief groove 136 along the depth direction of the pressure relief groove 136. The pressure relief groove 136 may be provided on the side of the first wall portion 13 facing the electrode assembly 2, so that the notch of the pressure relief groove 136 faces the electrode assembly 2; the pressure relief groove 136 may also be provided on the side of the first wall portion 13 away from the electrode assembly 2, so that the notch of the pressure relief groove 136 faces the outside of the battery cell 10. There are many ways to form the pressure relief groove 136, such as stamping, laser etching, milling, etc. The pressure relief groove 136 can be a groove extending along a closed trajectory, which can be a circular trajectory, a rectangular trajectory, etc. The pressure relief groove 136 can also be a groove extending along a non-closed trajectory, which can be an H-shaped trajectory, a V-shaped trajectory, a C-shaped trajectory, a Y-shaped trajectory, etc.

[0286] As an example, in Fig. 27 and Fig.28 In the illustrated embodiment, along the first direction Z, the wall body 132 has a third surface 1321, which is the outer surface of the wall body 132 and is also the surface of the first wall portion 13 farthest from the electrode assembly 2 along the first direction Z. The wall body 132 is provided with a groove 137, the inner space of which may be cylindrical, prism-shaped, etc. The groove 137 is recessed from the third surface 1321 toward the direction close to the electrode assembly 2, and the pressure relief groove 136 is provided at the groove bottom wall 138 of the groove, which is the portion of the first wall portion 13 located at the bottom of the groove 137 along the depth direction of the groove 137. A recess 1381 is provided on the side of the groove bottom wall 138 of the groove away from the electrode assembly 2, and a reinforcing rib 1382 is formed on the side of the groove bottom wall 138 of the groove facing the electrode assembly 2 at a position corresponding to the recess 1381, and the reinforcing rib 1382 has the same shape as the recess 1381, and is substantially X-shaped. The pressure relief groove 136 is an annular groove, and the pressure relief groove 136 surrounds the outer side of the reinforcing rib 1382. The weak portion 1311 defines a pressure relief area 1312, and the recess 1381 and the reinforcing rib 1382 are located in the pressure relief area 1312. When the battery cell 10 is depressurized, the wall body 132 will be split along the weak portion 1311, thereby opening the pressure relief area 1312. The reinforcing rib 1382 is used to strengthen the pressure relief area 1312, improve the deformation resistance of the pressure relief area 1312, and reduce the risk of deformation of the pressure relief area 1312 due to changes in the internal pressure of the battery cell 10, resulting in premature rupture of the weak portion 1311 due to fatigue.

[0287] In some embodiments, the housing 1 includes a shell 11 and an end cover 12 , wherein the shell 11 is formed with an opening at at least one end along the first direction Z, and the end cover 12 closes the opening. At least one end cover 12 is a first wall portion 13 .

[0288] The housing 11 may have an opening formed at only one end along the first direction Z, and one end cap 12 is provided accordingly. The housing 11 may have openings formed at both ends along the first direction Z, and two end caps 12 are provided accordingly, and the two end caps 12 respectively close the two opposite openings of the housing 11, and one end cap 12 may be the first wall portion 13, or both end caps 12 may be the first wall portion 13. It can be understood that the first wall portion 13 and the side wall 14 are provided separately.

[0289] In this embodiment, at least one end cover 12 is the first wall portion 13 , so that at least one end cover 12 is provided with a pressure relief mechanism 131 , which reduces the difficulty of molding or installing the pressure relief mechanism 131 .

[0290] In some embodiments, the battery cell 10 is a cylindrical battery cell.

[0291] It can be understood that the battery cell 10 is cylindrical, and the axial direction of the battery cell 10 is parallel to the first direction Z.

[0292] An embodiment of the present application provides a battery 100, comprising a battery cell 10 provided in any one of the above embodiments.

[0293] An embodiment of the present application provides an electrical device, including a battery cell 10 provided by any one of the above embodiments, and the battery cell 10 is used to provide electrical energy to the electrical device.

[0294] In addition, please refer to Figure 8-Figure 11The embodiment of the present application provides a cylindrical battery cell, including a shell 1, an electrode assembly 2, a pressure relief mechanism 131, an electrode terminal 3, a separator 4, a first current collecting member 5, and a second current collecting member 6. The electrode assembly 2, the separator 4, the first current collecting member 5, and the second current collecting member 6 are all accommodated in the shell 1. The shell 1 includes a shell 11 and an end cover 12. The shell 11 has an opening only at one end along the first direction Z, and the end cover 12 closes the opening. The first direction Z is parallel to the axial direction of the shell 1. The electrode assembly 2 includes a main body 21, a first pole ear 22 and a second pole ear 23. The polarities of the first pole ear 22 and the second pole ear 23 are opposite. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at both ends of the main body 21. The electrode terminal 3 is insulated and installed on the wall of the shell 11 opposite to the end cover 12. The electrode terminal 3 is electrically connected to the second pole ear 23 through the second current collecting member 6. Along the first direction Z, the first current collecting member 5 and the separator 4 are arranged between the electrode assembly 2 and the end cover 12, the first current collecting member 5 is located between the electrode assembly 2 and the separator 4, the first current collecting member 5 electrically connects the separator 4 and the first electrode tab 22, and the separator 4 electrically connects the first current collecting member 5 and the end cover 12.

[0295] Among them, the end cover 12 is the first wall portion 13 of the outer shell 1, and the pressure relief mechanism 131 is arranged on the first wall portion 13. The pressure relief mechanism 131 is configured to be at least partially opened when the battery cell 10 releases pressure. The partition 4 is provided with an avoidance space 41. The avoidance space 41 is a through hole that passes through both ends of the partition 4 along the first direction Z. The avoidance space 41 is configured to avoid the pressure relief mechanism 131. The projection of the partition 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131.

[0296] A first flow guide channel 7 is formed between the first pole ear 22 and the side wall 14 of the housing 11. The separator 4 includes a ring body 43 and a plurality of protrusions 44, the ring body 43 has a first surface 431 and a second surface 432 opposite to each other, the avoidance space 41 runs through the first surface 431 and the second surface 432, and the plurality of protrusions 44 are arranged on the ring body 43 at intervals along the circumferential direction X of the ring body, the protrusions 44 at least partially protrude from the first surface 431, and a second flow guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431, and the second flow guide channel 42 connects the avoidance space 41 and the first flow guide channel 7. Along the first direction Z, the protrusions 44 directly abut against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0297] The convex portion 44 includes a first portion 441 formed by integrally bending a plate, the first portion 441 includes a first bending portion 4411 and a first connecting portion 4412, the first bending portion 4411 is connected to the outer peripheral surface 433 of the ring body, the first connecting portion 4412 is connected to the first bending portion 4411, the first connecting portion 4412 is located on the side of the first surface 431 away from the second surface 432, and a gap is set between the first connecting portion 4412 and the first surface 431. Along the first direction Z, the first connecting portion 4412 directly abuts against the first current collecting member 5. Among them, the first connecting portion 4412 can be a single-layer structure, or a multi-layer structure formed by at least one bending.

[0298] Please refer to Fig.17 and Fig.18 The present application provides a cylindrical battery cell, including a housing 1, an electrode assembly 2, a pressure relief mechanism 131, and an electrode terminal 3 ( Fig.17 and Fig.18 not shown), separator 4, first current collecting member 5 ( Fig.17 and Fig.18 The electrode assembly 2, the separator 4, the first current collecting member 5, and the second current collecting member 6 are all contained in the outer shell 1. The outer shell 1 includes a shell 11 and an end cover 12. The shell 11 has an opening at only one end along the first direction Z, and the end cover 12 closes the opening. The first direction Z is parallel to the axial direction of the outer shell 1. The electrode assembly 2 includes a main body 21, a first pole ear 22 and a second pole ear 23. The polarities of the first pole ear 22 and the second pole ear 23 are opposite. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at both ends of the main body 21. The electrode terminal 3 is insulated and installed on the wall of the shell 11 opposite to the end cover 12. The electrode terminal 3 is electrically connected to the second pole ear 23 through the second current collecting member 6. Along the first direction Z, the first current collecting member 5 and the separator 4 are arranged between the electrode assembly 2 and the end cover 12, the first current collecting member 5 is located between the electrode assembly 2 and the separator 4, the first current collecting member 5 electrically connects the separator 4 and the first electrode tab 22, and the separator 4 electrically connects the first current collecting member 5 and the end cover 12.

[0299] Among them, the end cover 12 is the first wall portion 13 of the outer shell 1, and the pressure relief mechanism 131 is arranged on the first wall portion 13. The pressure relief mechanism 131 is configured to be at least partially opened when the battery cell 10 releases pressure. The partition 4 is provided with an avoidance space 41. The avoidance space 41 is a through hole that passes through both ends of the partition 4 along the first direction Z. The avoidance space 41 is configured to avoid the pressure relief mechanism 131. The projection of the partition 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131.

[0300] A first flow guide channel 7 is formed between the first pole ear 22 and the side wall 14 of the housing 11. The separator 4 includes a ring body 43 and a plurality of protrusions 44, the ring body 43 has a first surface 431 and a second surface 432 opposite to each other, the avoidance space 41 runs through the first surface 431 and the second surface 432, and the plurality of protrusions 44 are arranged on the ring body 43 at intervals along the circumferential direction X of the ring body, the protrusions 44 at least partially protrude from the first surface 431, and a second flow guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431, and the second flow guide channel 42 connects the avoidance space 41 and the first flow guide channel 7. Along the first direction Z, the protrusions 44 directly abut against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0301] The convex portion 44 includes a first portion 441 formed by integrally bending a plate and a second portion 442 formed by integrally bending a plate. The first portion 441 includes a first bending portion 4411 and a first connecting portion 4412, wherein the first bending portion 4411 is connected to the outer peripheral surface 433 of the ring body, the first connecting portion 4412 is connected to the first bending portion 4411, and the first connecting portion 4412 is located on the side of the first surface 431 away from the second surface 432. The first connecting portion 4412 can be a single-layer structure or a multi-layer structure formed by at least one bending. The second portion 442 includes a third bending portion 4421 and a second connecting portion 4422, wherein the third bending portion 4421 is connected to the inner peripheral surface 434 of the ring body, the second connecting portion 4422 is connected to the third bending portion 4421, and the second connecting portion 4422 is located on the side of the first surface 431 away from the second surface 432. The second connecting portion 4422 can be a single-layer structure or a multi-layer structure formed by at least one bending. Along the first direction Z, the second connection portion 4422 is closer to the electrode assembly 2 than the first connection portion 4412 , and the second connection portion 4422 directly abuts against the first current collecting member 5 .

[0302] Please refer to Fig.19 and Fig. 20 The present application embodiment provides a cylindrical battery cell, including a housing 1, an electrode assembly 2, a pressure relief mechanism 131, and an electrode terminal 3 ( Fig.19 and Fig. 20 not shown), separator 4, first current collecting member 5 ( Fig.19 and Fig. 20The electrode assembly 2, the separator 4, the first current collecting member 5, and the second current collecting member 6 are all contained in the outer shell 1. The outer shell 1 includes a shell 11 and an end cover 12. The shell 11 has an opening at only one end along the first direction Z, and the end cover 12 closes the opening. The first direction Z is parallel to the axial direction of the outer shell 1. The electrode assembly 2 includes a main body 21, a first pole ear 22 and a second pole ear 23. The polarities of the first pole ear 22 and the second pole ear 23 are opposite. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at both ends of the main body 21. The electrode terminal 3 is insulated and installed on the wall of the shell 11 opposite to the end cover 12. The electrode terminal 3 is electrically connected to the second pole ear 23 through the second current collecting member 6. Along the first direction Z, the first current collecting member 5 and the separator 4 are arranged between the electrode assembly 2 and the end cover 12, the first current collecting member 5 is located between the electrode assembly 2 and the separator 4, the first current collecting member 5 electrically connects the separator 4 and the first electrode tab 22, and the separator 4 electrically connects the first current collecting member 5 and the end cover 12.

[0303] Among them, the end cover 12 is the first wall portion 13 of the outer shell 1, and the pressure relief mechanism 131 is arranged on the first wall portion 13. The pressure relief mechanism 131 is configured to be at least partially opened when the battery cell 10 releases pressure. The partition 4 is provided with an avoidance space 41. The avoidance space 41 is a through hole that passes through both ends of the partition 4 along the first direction Z. The avoidance space 41 is configured to avoid the pressure relief mechanism 131. The projection of the partition 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131.

[0304] A first flow guide channel 7 is formed between the first pole ear 22 and the side wall 14 of the housing 11. The separator 4 includes a ring body 43 and a plurality of protrusions 44, the ring body 43 has a first surface 431 and a second surface 432 opposite to each other, the avoidance space 41 runs through the first surface 431 and the second surface 432, and the plurality of protrusions 44 are arranged on the ring body 43 at intervals along the circumferential direction X of the ring body, the protrusions 44 at least partially protrude from the first surface 431, and a second flow guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431, and the second flow guide channel 42 connects the avoidance space 41 and the first flow guide channel 7. Along the first direction Z, the protrusions 44 directly abut against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0305] The convex portion 44 includes a first portion 441 formed by integrally bending a plate and a second portion 442 formed by integrally bending a plate. The first portion 441 includes a first bending portion 4411 and a first connecting portion 4412, wherein the first bending portion 4411 is connected to the outer peripheral surface 433 of the ring body, the first connecting portion 4412 is connected to the first bending portion 4411, and the first connecting portion 4412 is located on the side of the first surface 431 away from the second surface 432. The first connecting portion 4412 can be a single-layer structure or a multi-layer structure formed by at least one bending. The second portion 442 includes a third bending portion 4421 and a second connecting portion 4422, wherein the third bending portion 4421 is connected to the inner peripheral surface 434 of the ring body, the second connecting portion 4422 is connected to the third bending portion 4421, and the second connecting portion 4422 is located on the side of the first surface 431 away from the second surface 432. The second connecting portion 4422 can be a single-layer structure or a multi-layer structure formed by at least one bending. Along the first direction Z, the first connection portion 4412 is closer to the electrode assembly 2 than the second connection portion 4422 , and the first connection portion 4412 directly abuts against the first current collecting member 5 .

[0306] Please refer to Fig.21 and Fig. 22 The present application embodiment provides a cylindrical battery cell, including a housing 1, an electrode assembly 2, a pressure relief mechanism 131, and an electrode terminal 3 ( Fig.21 and Fig. 22 not shown), separator 4, first current collecting member 5 ( Fig.21 and Fig. 22 The electrode assembly 2, the separator 4, the first current collecting member 5, and the second current collecting member 6 are all contained in the outer shell 1. The outer shell 1 includes a shell 11 and an end cover 12. The shell 11 has an opening at only one end along the first direction Z, and the end cover 12 closes the opening. The first direction Z is parallel to the axial direction of the outer shell 1. The electrode assembly 2 includes a main body 21, a first pole ear 22 and a second pole ear 23. The polarities of the first pole ear 22 and the second pole ear 23 are opposite. Along the first direction Z, the first pole ear 22 and the second pole ear 23 are respectively arranged at both ends of the main body 21. The electrode terminal 3 is insulated and installed on the wall of the shell 11 opposite to the end cover 12. The electrode terminal 3 is electrically connected to the second pole ear 23 through the second current collecting member 6. Along the first direction Z, the first current collecting member 5 and the separator 4 are arranged between the electrode assembly 2 and the end cover 12, the first current collecting member 5 is located between the electrode assembly 2 and the separator 4, the first current collecting member 5 electrically connects the separator 4 and the first electrode tab 22, and the separator 4 electrically connects the first current collecting member 5 and the end cover 12.

[0307] Among them, the end cover 12 is the first wall portion 13 of the outer shell 1, and the pressure relief mechanism 131 is arranged on the first wall portion 13. The pressure relief mechanism 131 is configured to be at least partially opened when the battery cell 10 releases pressure. The partition 4 is provided with an avoidance space 41. The avoidance space 41 is a through hole that passes through both ends of the partition 4 along the first direction Z. The avoidance space 41 is configured to avoid the pressure relief mechanism 131. The projection of the partition 4 along the first direction Z does not overlap with the projection of the pressure relief mechanism 131.

[0308] A first flow guide channel 7 is formed between the first pole ear 22 and the side wall 14 of the housing 11. The separator 4 includes a ring body 43 and a plurality of protrusions 44, the ring body 43 has a first surface 431 and a second surface 432 opposite to each other, the avoidance space 41 runs through the first surface 431 and the second surface 432, and the plurality of protrusions 44 are arranged on the ring body 43 at intervals along the circumferential direction X of the ring body, the protrusions 44 at least partially protrude from the first surface 431, and a second flow guide channel 42 is formed between the parts of two adjacent protrusions 44 protruding from the first surface 431, and the second flow guide channel 42 connects the avoidance space 41 and the first flow guide channel 7. Along the first direction Z, the protrusions 44 directly abut against the first current collecting member 5, and the first wall portion 13 directly abuts against the ring body 43.

[0309] The convex portion 44 includes a second portion 442 formed by integrally bending a plate, the second portion 442 includes a third bending portion 4421 and a second connecting portion 4422, the third bending portion 4421 is connected to the inner circumferential surface 434 of the ring body, the second connecting portion 4422 is connected to the third bending portion 4421, the second connecting portion 4422 is located on the side of the first surface 431 away from the second surface 432, and the second connecting portion 4422 is provided with a gap from the first surface 431. Along the first direction Z, the second connecting portion 4422 directly abuts against the first current collecting member 5. The second connecting portion 4422 may be a single-layer structure or a multi-layer structure formed by at least one bending.

[0310] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0311] The above embodiments are only used to illustrate the technical solution of the present application and are not used 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 battery cell, characterized in that: include: A housing having a first wall portion; a pressure relief mechanism, disposed on the first wall portion, the pressure relief mechanism being configured to at least partially open when the battery cell is depressurized; an electrode assembly, contained in the housing, the electrode assembly being arranged opposite to the first wall portion along a first direction; A separator is arranged between the first wall portion and the electrode assembly, and the separator is provided with an escape space. Along the first direction, the projection of the pressure relief mechanism is at least partially located in the escape space, and the escape space is configured to escape the pressure relief mechanism.

2. The battery cell according to claim 1, characterized in that: The avoidance space is a through hole that penetrates through both ends of the partition along the first direction.

3. The battery cell according to claim 2, characterized in that: Along the first direction, a projection of the partition does not overlap with a projection of the pressure relief mechanism.

4. The battery cell according to claim 1, characterized in that: The pressure relief mechanism comprises a weak portion, which is configured to be at least partially split when the battery cell is pressure-relieved, and a projection of the weak portion along the first direction is completely located within the avoidance space.

5. The battery cell according to claim 1, characterized in that: The housing includes a side wall, the side wall is arranged around the first wall portion, and the first wall portion is arranged at one end of the side wall along the first direction; A first electrode ear is formed at one end of the electrode assembly close to the first wall portion along the first direction, a first guide channel is formed between the first electrode ear and the side wall, the separator directly or indirectly abuts against the first electrode ear along the first direction, and the separator is provided with a second guide channel, which connects the first guide channel and the avoidance space.

6. The battery cell according to claim 1, characterized in that: The electrode assembly is formed with a first electrode tab at one end close to the first wall portion along the first direction, and the separator comprises: A ring body, wherein along the first direction, the ring body has a first surface and a second surface opposite to each other, and the avoidance space runs through the first surface and the second surface; A plurality of convex portions are arranged on the ring body at intervals along the circumference of the ring body, the convex portions at least partially protrude from the first surface, a second guide channel is formed between the portions of two adjacent convex portions protruding from the first surface, and the second guide channel is connected to the avoidance space; Wherein, along the first direction, one of the ring body and the protrusion directly or indirectly abuts against the first pole lug, and the first wall portion directly or indirectly abuts against the other of the ring body and the protrusion.

7. The battery cell according to claim 6, characterized in that: The battery cell comprises: A first current collecting member is disposed between the separator and the first electrode tab along the first direction, the first current collecting member electrically connects the separator and the first electrode tab, and the first wall portion is electrically connected to the separator; Along the first direction, the protrusion directly abuts against the first current collecting member, the first current collecting member directly abuts against the first electrode tab, and the first wall portion directly abuts against the ring body.

8. The battery cell according to claim 7, characterized in that: The ring body is welded to the first wall portion to form a first weld print area, and at least one of the protrusions is welded to the first current collecting member to form a second weld print area. Along the first direction, a projection of the first weld print area does not overlap with a projection of the second weld print area.

9. The battery cell according to claim 6, characterized in that: The convex portion includes a first part, the first part includes a first bending portion and a first connecting portion, the first bending portion is connected to the outer peripheral surface of the ring body, the first connecting portion is connected to the first bending portion, and the first connecting portion is at least partially located on the side of the first surface away from the second surface.

10. The battery cell according to claim 9, characterized in that: Along the first direction, the first connecting portion and the first surface are spaced apart from each other.

11. The battery cell according to claim 9, characterized in that: The first connecting portion comprises: A plurality of first stacked portions are located on a side of the first surface away from the second surface, and the plurality of first stacked portions are arranged along the first direction; The second bending portion connects two adjacent first stacking portions.

12. The battery cell according to claim 11, characterized in that: Along the first direction, two adjacent first stacking parts are arranged with a gap.

13. The battery cell according to claim 11, characterized in that: Along the first direction, one of the first stacked portions farthest from the first surface is connected to the first bending portion; or, along the first direction, one of the first stacked portions closest to the first surface is connected to the first bending portion.

14. The battery cell according to claim 9, characterized in that: The first part is formed by integrally bending a plate.

15. The battery cell according to claim 9, characterized in that: The convex portion includes a second portion, the second portion includes a third bent portion and a second connecting portion, the third bent portion is connected to the inner circumferential surface of the ring body, the second connecting portion is connected to the third bent portion, the second connecting portion is at least partially located on a side of the first surface away from the second surface, and the second connecting portion and the first connecting portion are arranged along the first direction; The first connection portion is closer to the first surface along the first direction than the second connection portion; or the second connection portion is closer to the first surface along the first direction than the first connection portion.

16. The battery cell according to claim 6, characterized in that: The convex portion includes a second part, the second part includes a third bending portion and a second connecting portion, the third bending portion is connected to the inner circumference of the ring body, the second connecting portion is connected to the third bending portion, and the second connecting portion is at least partially located on the side of the first surface away from the second surface.

17. The battery cell according to claim 16, characterized in that: Along the first direction, the second connection portion is disposed with a gap from the first surface.

18. The battery cell according to claim 16, characterized in that: The second connecting portion comprises: A plurality of second stacked portions, located on a side of the first surface away from the second surface, and the plurality of second stacked portions are arranged along the first direction; The fourth bending portion connects two adjacent second stacking portions.

19. The battery cell according to claim 18, characterized in that: Along the first direction, two adjacent second stacking parts are arranged with a gap.

20. The battery cell according to claim 18, characterized in that Along the first direction, one of the second stacked portions farthest from the first surface is connected to the third bending portion; or, along the first direction, one of the second stacked portions closest to the first surface is connected to the third bending portion.

21. The battery cell according to claim 15, characterized in that The second part is formed by integrally bending a plate.

22. The battery cell according to claim 6, characterized in that: Along the first direction, the minimum thickness of the ring body is D, and D≥0.3 mm.

23. The battery cell according to claim 6, characterized in that: The separator electrically connects the first wall portion and the first electrode tab. Along the circumference of the ring body, the sum of the maximum dimensions of all the protrusions is A1, the sum of the maximum dimensions of all the second flow guide channels is A2, and 0.1≤A1 / (A1+A2)≤0.

8.

24. The battery cell according to any one of claims 1 to 23, characterized in that: The separator electrically connects the first wall portion and the electrode assembly.

25. The battery cell according to claim 24, characterized in that The battery cell comprises: A first current collecting member is disposed between the separator and the electrode assembly along the first direction, the first current collecting member electrically connects the separator and the electrode assembly, and a projection of the first current collecting member covers the avoidance space along the first direction.

26. The battery cell according to claim 25, characterized in that The separator is welded to the first wall portion to form a first weld print area, and the separator is welded to the first current collecting member to form a second weld print area. Along the first direction, a projection of the first weld print area does not overlap with a projection of the second weld print area.

27. The battery cell according to claim 25, characterized in that A first electrode tab is formed at one end of the electrode assembly close to the first wall portion along the first direction, and the material of the first electrode tab is different from that of the first wall portion; Among them, the material of the first current collecting component is the same as that of the first pole ear, and the first current collecting component is welded to the first pole ear; the material of the separator is the same as that of the first wall portion, and the separator is welded to the first wall portion; the first current collecting component is compositely connected to the separator.

28. The battery cell according to any one of claims 25 to 27, characterized in that: The electrode assembly is provided with a first central hole, the first current collecting member is provided with a second central hole, and the second central hole communicates with the first central hole and the avoidance space.

29. The battery cell according to any one of claims 1 to 23, characterized in that: The first wall portion includes a wall body and a supporting portion, the wall body is provided with the pressure relief mechanism, and the supporting portion is arranged around the outer edge of the wall body; Along the first direction, the abutting portion protrudes from the wall body in a direction approaching the electrode assembly and directly or indirectly abuts against the separator.

30. The battery cell according to claim 29, characterized in that The housing includes a side wall separately provided with the first wall portion, the side wall is provided around the first wall portion, and the first wall portion is provided at one end of the side wall along the first direction; At least a portion of the abutting portion is accommodated in the side wall and forms a positioning fit with the side wall.

31. The battery cell according to any one of claims 1 to 23, characterized in that: The pressure relief mechanism is integrally formed with the first wall portion; or, the pressure relief mechanism and the first wall portion are separately provided, and the pressure relief mechanism is installed on the first wall portion.

32. The battery cell according to any one of claims 1 to 23, characterized in that: The housing comprises: A housing, at least one end of which is formed with an opening along the first direction; an end cap for closing the opening; Wherein, at least one of the end covers is the first wall portion.

33. The battery cell according to any one of claims 1 to 23, characterized in that: The battery cell is a cylindrical battery cell.

34. A battery, characterized in that: Comprising the battery cell according to any one of claims 1-33.

35. An electrical device, characterized in that: It comprises a battery cell as described in any one of claims 1 to 33, and the battery cell is used to provide electrical energy to the electrical device.

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