Battery cell, battery, and electric device

Abstract

A battery cell, a battery, and an electric device, relating to the technical field of batteries. The battery cell comprises a casing assembly, an electrode assembly, and a first current-collecting component. The casing assembly comprises a first electrode extraction portion for inputting or outputting electric energy. The electrode assembly and the first current-collecting component are both accommodated in the casing assembly, and in a first direction, the first current-collecting component is located at one end of the electrode assembly, and the first current-collecting component is electrically connected to the first electrode extraction portion and the electrode assembly. The first current-collecting component is provided with a through hole, the through hole passes through the first current-collecting component in the first direction, the orthographic projection of the hole wall surface of the through hole in the first direction is provided with a first corner, and part of the orthographic projection of the through hole in the first direction is located within the first corner. According to the battery cell, the acting force acting on the first current-collecting component during pressure relief can cause a stress concentration at the first corner to tear the first current-collecting component, so that the area of the first current-collecting component through which a thermal runaway gas passes can be enlarged, thereby improving the exhaust efficiency of the battery cell.

Description

Battery cells, batteries and electrical devices

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 2023107555490, filed on June 26, 2023, entitled “Battery Cell, Battery and Electrical Device,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] 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

[0004] New energy vehicles have experienced rapid growth in recent years. Within the electric vehicle sector, power batteries, as the power source, play an irreplaceable and important role. With the vigorous promotion of new energy vehicles, demand for power battery products is also growing. As core components of new energy vehicles, batteries have high requirements for operational reliability. Battery cells typically consist of a housing and an electrode assembly housed within the housing. However, existing battery cells often present risks of fire and explosion during use, resulting in low reliability.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can effectively improve the reliability of the battery cell.

[0007] In a first aspect, an embodiment of the present application provides a battery cell, comprising a housing assembly, an electrode assembly and a first current collecting member; the housing assembly comprises a first electrode lead-out portion for inputting or outputting electrical energy; the electrode assembly is accommodated in the housing assembly; the first current collecting member is accommodated in the housing assembly, and along a first direction, the first current collecting member is located at one end of the electrode assembly, and the first current collecting member electrically connects the first electrode lead-out portion and the electrode assembly; wherein, the first current collecting member is provided with a through hole, the through hole passes through the first current collecting member along the first direction, a hole wall surface of the through hole forms a first fold angle along the orthographic projection of the through hole in the first direction, and a portion of the orthographic projection of the through hole along the first direction is located within the first fold angle.

[0008] In the above technical solution, a through hole is provided on the first current collecting member, which passes through both sides of the first current collecting member along the first direction. A first fold angle is formed on the wall surface of the through hole along the orthographic projection of the through hole in the first direction, and a part of the orthographic projection of the through hole along the first direction is located within the first fold angle, so that the first fold angle formed on the wall surface of the through hole is an fold angle structure protruding outward away from the through hole, so that when the battery cell thermally runs away and releases internal gas, the force acting on the first current collecting member can generate stress concentration at the first fold angle of the wall surface of the through hole, so as to facilitate tearing the first current collecting member from the first fold angle of the wall surface of the through hole, thereby expanding the area of ​​the first current collecting member for the thermal runaway gas to pass through, so as to reduce the obstruction of the thermal runaway gas inside the battery cell by the first current collecting member, and thus effectively improve the exhaust smoothness and exhaust efficiency of the battery cell, so as to reduce the risk of fire and explosion of the battery cell due to poor pressure relief effect, which is conducive to improving the reliability of the battery cell.

[0009] In some embodiments, the angle of the first folded corner facing the through hole is β, satisfying 0°<β≤90°.

[0010] In the above technical solution, by setting the angle of the first fold corner facing the through hole to be greater than 0 degrees and less than or equal to 90 degrees, the first fold corner is realized as a fold corner structure protruding outward away from the through hole. At the same time, it can also effectively alleviate the phenomenon that the thermal runaway gas has difficulty tearing the first current collecting component from the first fold corner due to the excessively large angle of the first fold corner, which is conducive to improving the tearing effect of the first current collecting component after the thermal runaway gas generates stress concentration at the first fold corner.

[0011] In some embodiments, the angle of the first folded corner facing the through hole is β, which satisfies 30°≤β≤90°.

[0012] In the above technical solution, by setting the angle of the first fold angle facing the through hole to 30 degrees to 90 degrees, the phenomenon that the processing difficulty of the through hole is too great due to the first fold angle being too small can be alleviated, thereby reducing the manufacturing difficulty and manufacturing cost of the first current collecting component.

[0013] In some embodiments, a plurality of first fold angles are formed on the wall surface of the through hole, and the plurality of first fold angles are arranged in sequence along the circumference of the through hole.

[0014] In the above technical solution, a plurality of first fold angles are formed on the wall surface of the through hole, and the plurality of first fold angles are arranged in sequence along the circumference of the through hole, so that the thermal runaway gas can tear the first current collecting member from the plurality of first fold angles after generating stress concentration at the plurality of first fold angles on the wall surface of the through hole, so that the first current collecting member can be torn from multiple positions, thereby facilitating further expansion of the area of ​​the first current collecting member for the thermal runaway gas to pass through, so as to further reduce the obstruction of the first current collecting member to the thermal runaway gas inside the battery cell, thereby effectively improving the exhaust smoothness and exhaust efficiency of the battery cell.

[0015] In some embodiments, along the circumference of the through hole, the hole wall surface of the through hole includes a plurality of first wall surfaces, and the first angle is formed between every two adjacent first wall surfaces.

[0016] In the above technical solution, by setting the hole wall surface of the through hole to have multiple first wall surfaces arranged along the circumference of the through hole, and forming a first fold angle between each two adjacent first wall surfaces, the orthographic projection of the through hole along the first direction is a polygonal structure, so that the hole wall surface of the through hole is formed with multiple first fold angles arranged in sequence along the circumference of the through hole. The structure is simple and easy to implement.

[0017] In some embodiments, the angles of the plurality of first fold angles are the same.

[0018] In the above technical solution, by setting the multiple first fold angles to be the same, the angles between each adjacent two first wall surfaces of the multiple first wall surfaces of the hole wall of the through hole are the same, so as to realize a structure in which the positive projection of the through hole along the first direction is a regular polygon. On the one hand, this facilitates the manufacturing and processing of the through hole, which is conducive to reducing the manufacturing difficulty of the first current collecting component. On the other hand, it makes the force acting to tear the first current collecting component from the multiple first fold angles the same, so that the thermal runaway gas can tear the first current collecting component from the multiple first fold angles.

[0019] In some embodiments, the first current collecting member is a disc-shaped structure, and a central axis of the first current collecting member coincides with a central axis of the through hole.

[0020] In the above technical solution, by setting the central axis of the first current collecting member to coincide with the central axis of the through hole, the through hole is located at the center of the first current collecting member. Therefore, when the first current collecting member is electrically connected to the electrode assembly and the first electrode lead-out portion, the area of ​​the first current collecting member surrounding the outside of the through hole can be electrically connected to the electrode assembly and the first electrode lead-out portion, without the need to perform secondary positioning of the first current collecting member to avoid the through hole, which helps to reduce the difficulty of assembling the first current collecting member into the housing assembly, thereby improving the assembly efficiency of the battery cell.

[0021] In some embodiments, along the circumference of the through hole, every two adjacent first wall surfaces are connected by a chamfered surface.

[0022] In the above technical solution, by connecting two adjacent first wall surfaces through a chamfered surface, it is helpful to reduce the difficulty of machining the through hole on the first current collecting member and reduce the requirements for the equipment for machining the through hole on the first current collecting member.

[0023] In some embodiments, the orthographic projection of the through hole along the first direction is a polygon.

[0024] In the above technical solution, by setting the through hole to be a polygonal structure with a positive projection along the first direction, a first fold angle is formed between every two adjacent sides of the polygon, so that the wall surface of the through hole is formed with multiple first fold angles arranged in sequence along the circumference of the through hole. The structure is simple and easy to implement.

[0025] In some embodiments, the orthographic projection of the through hole along the first direction is a regular polygon.

[0026] In the above technical solution, by setting the through hole to be a regular polygonal structure with a positive projection along the first direction, the angles of the multiple first corners formed on the hole wall of the through hole are all the same, which, on the one hand, facilitates the manufacturing and processing of the through hole and helps to reduce the manufacturing difficulty of the first current collecting component. On the other hand, the force acting to tear the first current collecting component from the multiple first corners is the same, so that the thermal runaway gas can tear the first current collecting component from the multiple first corners.

[0027] In some embodiments, the orthographic projection of the through hole along the first direction is a triangle or a rectangle.

[0028] In the above technical solution, by setting the through hole to be a triangle or a rectangle in the positive projection along the first direction, the triangular hole or the rectangular hole of the through hole can facilitate the processing of the through hole on the first current collecting component, which is beneficial to reduce the processing difficulty of the through hole. On the other hand, it can effectively control the angle of the first folding angle to alleviate the phenomenon that the angle of the first folding angle is too large or too small.

[0029] In some embodiments, the wall surface of the through hole is formed with multiple fold angles. Along the circumference of the through hole, the wall surface of the through hole includes multiple first wall surfaces, and the fold angle is formed between each adjacent two first wall surfaces. The multiple fold angles include the first fold angle and the second fold angle, and the angle of the second fold angle facing the side of the through hole is greater than 180°.

[0030] In the above technical solution, a second fold angle is formed on the wall surface of the through hole, and the angle of the second fold angle facing the side of the through hole is greater than 180 degrees, so that the second fold angle is a fold angle structure protruding inward toward the through hole, so that the angle of the first fold angle can be adjusted through the second fold angle, so as to reduce the angle of the first fold angle, making it easier for the thermal runaway gas to tear the first collecting component from the first fold angle.

[0031] In some embodiments, the plurality of folded corners include a plurality of first folded corners and a plurality of second folded corners, and the first folded corners and the second folded corners are alternately arranged along the circumference of the through hole.

[0032] In the above technical solution, by setting the first fold angle and the second fold angle to be arranged alternately in the circumferential direction of the through hole, a first fold angle is formed between every two adjacent second fold angles, thereby facilitating the adjustment of the angle size of the first fold angle located between the two second fold angles through the two adjacent second fold angles.

[0033] In some embodiments, the angles of the plurality of first fold angles are the same, and the angles of the plurality of second fold angles are the same.

[0034] In the above technical solution, by setting multiple first fold angles to have the same angle, and setting multiple second fold angles to have the same angle, the orthographic projection of the through hole along the first direction is realized to have a regular shape, thereby facilitating the manufacture and processing of the through hole, which is beneficial to reducing the manufacturing difficulty of the first current collecting component, and on the other hand, the force acting to tear the first current collecting component from multiple first fold angles is the same, so that the thermal runaway gas can tear the first current collecting component from multiple first fold angles.

[0035] In some embodiments, the first current collecting member is a disc-shaped structure, and a central axis of the first current collecting member coincides with a central axis of the through hole.

[0036] In the above technical solution, by setting the central axis of the first current collecting member to coincide with the central axis of the through hole, the through hole is located at the center of the first current collecting member. Therefore, when the first current collecting member is electrically connected to the electrode assembly and the first electrode lead-out portion, the area of ​​the first current collecting member surrounding the outside of the through hole can be electrically connected to the electrode assembly and the first electrode lead-out portion, and there is no need to perform secondary positioning of the first current collecting member to avoid the through hole, which is conducive to reducing the difficulty of assembling the first current collecting member into the housing assembly, thereby improving the assembly efficiency of the battery cell.

[0037] In some embodiments, along the circumference of the through hole, every two adjacent first wall surfaces are connected by a chamfered surface.

[0038] In the above technical solution, by connecting two adjacent first wall surfaces through a chamfered surface, it is helpful to reduce the difficulty of machining the through hole on the first current collecting member and reduce the requirements for the equipment for machining the through hole on the first current collecting member.

[0039] In some embodiments, the electrode assembly has a central channel extending along the first direction, and at least a portion of an orthographic projection of the central channel along the first direction is located within the through-hole.

[0040] In the above technical solution, by setting at least a portion of the orthographic projection of the central channel of the electrode assembly along the first direction to be located in the through hole of the first current collecting member, the through hole and the central channel are made to overlap in the first direction, so that the thermal runaway gas generated in the central channel of the electrode assembly can directly act on the first fold corner of the hole wall of the through hole, thereby making it easier to tear the first current collecting member from the first fold corner.

[0041] In some embodiments, the battery cell is cylindrical, and the axis direction of the battery cell is the same as the first direction.

[0042] In the above technical solution, by arranging the battery cell into a cylindrical structure, the battery cell has the advantages of high capacity, long cycle life, and wide operating ambient temperature range.

[0043] In some embodiments, the housing assembly includes a housing, the electrode assembly is accommodated in the housing, and at least a portion of the housing forms the first electrode lead-out portion.

[0044] In the above technical solution, the shell assembly is provided with a shell. By using at least a portion of the shell as the first electrode lead-out portion, the electrode assembly can be connected to the shell through the first current collecting member to realize the input or output of electrical energy of the battery cell. The structure is simple and easy to assemble.

[0045] In some embodiments, the outer shell includes a shell and an end cover; the shell includes an integrally formed side wall and a bottom wall, the side wall is arranged around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall forms an opening opposite to the bottom wall, and the side wall and the bottom wall jointly define a accommodating cavity for accommodating the electrode assembly; the end cover closes the opening; wherein, the bottom wall is the first electrode lead-out portion.

[0046] In the above technical solution, by using the bottom wall of the shell as the first electrode lead-out part for outputting or inputting electrical energy of the battery cell, the first electrode lead-out part can be kept away from the end cover, thereby effectively alleviating the phenomenon that the force generated when the first electrode lead-out part is pulled or twisted by components such as the busbar component connected to the first electrode lead-out part acts between the end cover and the shell, thereby reducing the risk of connection failure between the end cover and the shell, and further helping to further reduce the risk of leakage of the battery cell during use.

[0047] In some embodiments, along the first direction, the first current collecting member is disposed between the end cover and the electrode assembly; wherein the first current collecting member is connected to the end cover, and the end cover is electrically connected to the side wall to electrically connect the first current collecting member and the bottom wall; or, the first current collecting member is connected to the side wall to electrically connect the first current collecting member and the bottom wall.

[0048] In the above technical solution, the first current collecting member is arranged between the end cover and the electrode assembly in the first direction, and the first current collecting member can be indirectly electrically connected to the shell through the end cover or the first current collecting member can be directly connected to the side wall of the shell, so as to achieve electrical connection between the first current collecting member and the bottom wall serving as the first electrode lead-out portion. The structure is simple and easy to implement.

[0049] In some embodiments, along the first direction, the first current collecting member is disposed between the bottom wall and the electrode assembly, and the first current collecting member is connected to the bottom wall.

[0050] In the above technical solution, by arranging the first current collecting member between the bottom wall and the electrode assembly in the first direction, the first current collecting member can be directly connected to the bottom wall, so as to realize electrical connection between the first current collecting member and the bottom wall serving as the first electrode lead-out portion. The structure is simple and easy to assemble.

[0051] In some embodiments, the outer shell includes a shell and an end cover; a receiving cavity with an opening is formed inside the shell, and the electrode assembly is received in the receiving cavity; the end cover closes the opening; wherein the end cover is the first electrode lead-out portion.

[0052] In the above technical solution, by using the end cover of the shell as the first electrode lead-out portion for outputting or inputting electrical energy of the battery cell, it is helpful to reduce the difficulty of assembling between the first current collecting member and the first electrode lead-out portion and between the first current collecting member and the electrode assembly, thereby improving the production efficiency of the battery cell.

[0053] In some embodiments, along the first direction, the first current collecting member is disposed between the end cover and the electrode assembly, and the first current collecting member is connected to the end cover.

[0054] In the above technical solution, by arranging the first current collecting member between the end cover and the electrode assembly in the first direction, the first current collecting member can be directly connected to the end cover, so as to realize electrical connection between the first current collecting member and the end cover serving as the first electrode lead-out portion. The structure is simple and easy to assemble.

[0055] In some embodiments, the housing assembly further includes a housing, and the electrode assembly is accommodated in the housing; wherein the first electrode lead-out portion is insulated and mounted on the housing, and along the first direction, at least a portion of the first current collecting member is disposed between the first electrode lead-out portion and the electrode assembly, and the first current collecting member is connected to the first electrode lead-out portion.

[0056] In the above technical solution, the shell assembly is also provided with a shell, and the first electrode lead-out part is insulated and installed on the shell so that the first electrode lead-out part can realize the input or output of electrical energy of the battery cell. The battery cell adopting this structure can reduce the risk of short circuit between the first electrode lead-out part and the shell, so as to improve the reliability of the battery cell.

[0057] In some embodiments, the outer shell includes a shell and an end cover; the shell includes an integrally formed side wall and a bottom wall, the side wall is arranged around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall forms an opening opposite to the bottom wall, and the side wall and the bottom wall jointly define a accommodating cavity for accommodating the electrode assembly; the end cover closes the opening; wherein, the first electrode lead-out portion is insulated and mounted on the end cover; or, the first electrode lead-out portion is insulated and mounted on the bottom wall.

[0058] In the above technical solution, the first electrode lead-out portion is insulated and mounted on the end cap, so that the first electrode lead-out portion can output or input electrical energy to the battery cell. Battery cells using this structure facilitate the insulated assembly of the first electrode lead-out portion on the outer shell, which helps reduce the difficulty of assembling the first electrode lead-out portion and the outer shell, thereby improving the production efficiency of the battery cells. Similarly, the first electrode lead-out portion is insulated and mounted on the bottom wall of the shell, so that the first electrode lead-out portion can output or input electrical energy to the battery cell. Battery cells using this structure keep the first electrode lead-out portion away from the end cap, thereby alleviating the force generated by the first electrode lead-out portion pulling or twisting the bottom wall on the end cap, thereby reducing the risk of connection failure between the end cap and the shell, and further helping to reduce the risk of leakage of the battery cell during use.

[0059] In some embodiments, the battery cell further includes a pressure relief mechanism; the pressure relief mechanism is disposed on the housing, and the pressure relief mechanism is configured to release internal pressure of the battery cell; wherein, along the first direction, the pressure relief mechanism is disposed opposite to the through hole.

[0060] In the above technical solution, by arranging the pressure relief mechanism on the outer shell, and making the pressure relief mechanism and the through hole relatively arranged along the first direction, at least part of the positive projection of the pressure relief mechanism along the first direction is located in the through hole. On the one hand, the internal pressure of the battery cell can be released through the pressure relief mechanism to reduce the risk of fire and explosion of the battery cell. On the other hand, after the first current collecting member is torn from the first corner by the thermal runaway gas, the thermal runaway gas can be directly discharged from the pressure relief mechanism, which can further reduce the phenomenon that the first current collecting member blocks the thermal runaway gas from being discharged from the interior of the battery cell through the pressure relief mechanism.

[0061] In a second aspect, an embodiment of the present application further provides a battery comprising the above-mentioned battery cell.

[0062] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery cell, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0064] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0065] FIG2 is an exploded view of the structure of a battery provided in some embodiments of the present application;

[0066] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0067] FIG4 is an exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0068] FIG5 is a cross-sectional view of a battery cell provided in some embodiments of the present application;

[0069] FIG6 is a partial cross-sectional view of a battery cell provided in some embodiments of the present application;

[0070] FIG7 is a schematic structural diagram of a first current collecting component provided in some embodiments of the present application;

[0071] FIG8 is a schematic structural diagram of a first current collecting component provided in yet other embodiments of the present application;

[0072] FIG9 is a schematic structural diagram of a first current collecting component provided in some further embodiments of the present application;

[0073] FIG10 is a schematic structural diagram of a first current collecting component provided in other embodiments of the present application.

[0074] Icon: 1000-vehicle; 100-battery; 10-casing; 11-first casing body; 12-second casing body; 20-battery cell; 21-housing assembly; 211-first electrode lead-out portion; 212-casing; 2121-shell; 2121a-opening; 2121b-side wall; 2121c-bottom wall; 2122-end cover; 2122a-convex portion; 213-second electrode lead-out portion; 22-electrode assembly; 221-first pole ear; 222-second pole ear; 223-center channel; 23-first current collecting member; 231-through hole; 2311-first wall surface; 2312-chamfered surface; 232-first fold angle; 233-second fold angle; 24-second current collecting member; 25-pressure relief mechanism; 200-controller; 300-motor; X-first direction. DETAILED DESCRIPTION

[0075] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0076] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0077] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0078] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0079] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0080] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0081] The term "plurality" used in this application refers to two or more (including two).

[0082] 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.

[0083] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.

[0084] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0085] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

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

[0087] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0088] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides may include but are not limited to lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 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 at least one of its modified compounds, etc.

[0089] In some embodiments, a positive electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam, among others. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not be provided with a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled and / or deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0090] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0091] As an example, the negative electrode current collector can be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium can be used. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can 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.).

[0092] 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.

[0093] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0094] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, 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.

[0095] 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.

[0096] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0097] In some embodiments, the separator is a separator membrane. There are many types of separator membranes, and any known separator membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0098] As an example, the separator can be made of at least one of fiberglass, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film. In the case of a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0099] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0100] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0101] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium bisoxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0102] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0103] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0104] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0105] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, or the like.

[0106] 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.

[0107] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0108] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0109] In some embodiments, the electrode assembly is a laminate structure.

[0110] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0111] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0112] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0113] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0114] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0115] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0116] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0117] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0118] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell or a battery cell of other shapes. Prismatic battery cells include but are not limited to square-shell battery cells, blade-shaped battery cells, and polygonal prismatic batteries, such as hexagonal prismatic batteries.

[0119] 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.

[0120] 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.

[0121] 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 housed in the case.

[0122] 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.

[0123] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0124] Batteries, with their outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient, are a vital component of today's new energy development. The development of battery technology requires simultaneous consideration of multiple design factors, including performance parameters such as energy density, cycle life, discharge capacity, and charge / discharge rate. Furthermore, battery safety must be considered. With the rapid development and increasing demand for batteries, demands for battery reliability and other aspects are also increasing.

[0125] For typical battery cells, the outer shell typically includes a housing and an end cap, with the end cap fitting over the opening of the housing. To facilitate assembly and production of the battery cells, particularly in cylindrical battery cells, a current collecting member is typically located within the housing. This current collecting member connects the electrode assembly's tabs to the electrode terminals located at one end of the housing, allowing the current collecting member to function as a transfer point, enabling the input and output of electrical energy from the battery cell. However, in battery cells with this structure, when thermal runaway occurs and internal pressure increases within the battery cell, the battery cell must vent the gases generated by the thermal runaway to relieve the internal pressure, thereby reducing the risk of explosion due to excessive internal pressure. However, the current collecting components arranged in the shell will block the thermal runaway gas generated inside the battery cell, which is not conducive to the battery cell to discharge the internal gas emissions out of the shell when thermal runaway occurs, resulting in poor exhaust smoothness and exhaust efficiency of the battery cell when releasing internal pressure, which can easily lead to risks such as fire and explosion in the battery cell during use, making the battery cell less reliable and causing greater safety hazards in the use of the battery cell.

[0126] Based on the above considerations, in order to address the issue of low reliability of battery cells during use, an embodiment of the present application provides a battery cell, comprising a housing assembly, an electrode assembly, and a first current collecting member. The housing assembly comprises a first electrode lead for inputting or outputting electrical energy. The electrode assembly and the first current collecting member are both housed within the housing assembly. Along a first direction, the first current collecting member is located at one end of the electrode assembly, and the first current collecting member electrically connects the first electrode lead and the electrode assembly. The first current collecting member is provided with a through hole, which extends through the first current collecting member along the first direction. The through hole wall surface forms a first angle along the orthographic projection of the through hole in the first direction, and a portion of the orthographic projection of the through hole in the first direction is located within the first angle.

[0127] In a battery cell of this structure, a through hole is provided on the first current collecting member, which passes through both sides of the first current collecting member in a first direction. A first fold angle is formed on the wall surface of the through hole along the orthographic projection of the through hole in the first direction, and a portion of the orthographic projection of the through hole in the first direction is located within the first fold angle, so that the first fold angle formed on the wall surface of the through hole is an fold angle structure that bulges outward away from the through hole, so that when the battery cell thermally runs away and releases internal gas, the force acting on the first current collecting member can generate stress concentration at the first fold angle of the wall surface of the through hole, so as to facilitate tearing the first current collecting member from the first fold angle of the wall surface of the through hole, thereby expanding the area of ​​the first current collecting member for the thermal runaway gas to pass through, so as to reduce the obstruction of the thermal runaway gas inside the battery cell by the first current collecting member, and thus can effectively improve the exhaust smoothness and exhaust efficiency of the battery cell, so as to reduce the risk of fire and explosion of the battery cell due to poor pressure relief effect, which is conducive to improving the reliability of the battery cell.

[0128] The battery cells disclosed in the embodiments of this application can be used, but are not limited to, in electrical devices such as vehicles, ships, or aircraft. A power supply system comprising the battery cells and batteries disclosed in this application can be used to construct such electrical devices. This helps mitigate the risk of fire and explosion during battery cell use, thereby improving the reliability of the battery cells.

[0129] The present invention provides an electric device that uses a battery as a power source. The electric device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, etc. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc. The spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0130] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0131] Please refer to Figure 1, which is a structural schematic diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000. The battery 100 can be arranged at the bottom of the vehicle 1000, or at the head of the vehicle 1000, or at the 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 or a power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0132] In some embodiments of the present application, the battery 100 can not only serve as the operating power source or usage power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0133] 2 and 3 , FIG2 is an exploded view of a battery 100 according to some embodiments of the present invention, and FIG3 is a schematic diagram of a battery cell 20 according to some embodiments of the present invention. The battery 100 includes a housing 10 and a battery cell 20 , wherein the battery cell 20 is accommodated in the housing 10 .

[0134] The housing 10 is used to provide assembly space for the battery cells 20 and can adopt a variety of structures. In some embodiments, the housing 10 can include a first housing body 11 and a second housing body 12. The first housing body 11 and the second housing body 12 cover each other, and the first housing body 11 and the second housing body 12 jointly define an assembly space for accommodating the battery cells 20. The second housing body 12 can be a hollow structure with one end open, and the first housing body 11 can be a plate-like structure. The first housing body 11 covers the open side of the second housing body 12, so that the first housing body 11 and the second housing body 12 jointly define the assembly space. The first housing body 11 and the second housing body 12 can also be hollow structures with one end open, and the open side of the first housing body 11 covers the open side of the second housing body 12.

[0135] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cuboid or a cube, etc. For example, in FIG2 , the box body 10 is in the shape of a cuboid.

[0136] In the battery 100, there can be one or more battery cells 20 disposed within the housing 10. When there are multiple battery cells 20 disposed within the housing 10, the multiple battery cells 20 can be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel configurations within the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed within the housing 10. Alternatively, the battery 100 can be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid configuration to form a battery module, which is then further connected in series, in parallel, or in a hybrid configuration to form a single structure, which is then housed within the housing 10.

[0137] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which is used to connect the multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20 .

[0138] Each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be cylindrical, prismatic, or in other shapes. For example, in FIG3 , the battery cell 20 is cylindrical.

[0139] According to some embodiments of the present application, referring to FIG3 and further to FIG4, FIG5, FIG6, and FIG7, FIG4 is an exploded view of a battery cell 20 provided in some embodiments of the present application, FIG5 is a cross-sectional view of a battery cell 20 provided in some embodiments of the present application, FIG6 is a partial cross-sectional view of a battery cell 20 provided in some embodiments of the present application, and FIG7 is a schematic diagram of the structure of a first current collecting member 23 provided in some embodiments of the present application. The present application provides a battery cell 20, which may include a housing assembly 21, an electrode assembly 22, and a first current collecting member 23. The housing assembly 21 includes a first electrode lead-out portion 211 for inputting or outputting electrical energy. The electrode assembly 22 is housed within the housing assembly 21. The first current collecting member 23 is housed within the housing assembly 21 and is located at one end of the electrode assembly 22 along a first direction X. The first current collecting member 23 electrically connects the first electrode lead-out portion 211 and the electrode assembly 22. The first current collecting member 23 is provided with a through hole 231, which penetrates the first current collecting member 23 along the first direction X. The hole wall surface of the through hole 231 forms a first corner 232 along the orthographic projection in the first direction X, and the part of the orthographic projection of the through hole 231 along the first direction X is located within the first corner 232.

[0140] The housing assembly 21 may include a housing 212, within which the electrode assembly 22 and the first current collecting member 23 are housed. The housing 212 may also be used to hold an electrolyte, such as an electrolyte solution. The housing 212 may have various structural forms, such as a cylinder or a prism. Similarly, the housing 212 may be made of various materials, such as copper, iron, aluminum, steel, or an aluminum alloy.

[0141] The housing assembly 21 includes a first electrode lead-out portion 211 for inputting or outputting electrical energy. The first electrode lead-out portion 211 is electrically connected to the electrode assembly 22, thereby outputting or inputting electrical energy from the battery cell 20. The first electrode lead-out portion 211 can output the negative electrode of the battery cell 20, that is, the first electrode lead-out portion 211 serves as the negative output electrode of the battery cell 20. Of course, the first electrode lead-out portion 211 can also output the positive electrode of the battery cell 20, that is, the first electrode lead-out portion 211 serves as the positive output electrode of the battery cell 20. Similarly, the first electrode lead-out portion 211 can have various structures. The first electrode lead-out portion 211 can be the housing 212, or it can be an electrode terminal insulated and mounted on the housing 212.

[0142] In some embodiments, the outer shell 212 may include a shell 2121 and an end cover 2122, and a accommodating cavity is formed inside the shell 2121, which is used to accommodate the electrode assembly 22, and the accommodating cavity has an opening 2121a, that is, the shell 2121 is a hollow structure with an opening 2121a at one end, wherein the shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c, and the side wall 2121b is arranged around the bottom wall 2121c. Along the first direction X, one end of the side wall 2121b is connected to the bottom wall 2121c, and the other end is enclosed to form an opening 2121a, and the end cover 2122 and the bottom wall 2121c are arranged opposite to each other along the first direction X, and the end cover 2122 covers the opening 2121a of the shell 2121 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte.

[0143] When assembling the battery cell 20 , the electrode assembly 22 may be placed into the housing 2121 first, and the housing 2121 may be filled with electrolyte. The end cap 2122 may then be placed over the opening 2121 a of the housing 2121 to complete the assembly of the battery cell 20 .

[0144] The housing 2121 can have a variety of shapes, such as a cylindrical or prismatic structure. The shape of the housing 2121 can be determined based on the specific shape of the electrode assembly 22. For example, if the electrode assembly 22 has a cylindrical structure, a cylindrical housing 2121 can be selected. Of course, the end cap 2122 can also have a variety of structures, such as a plate-like structure or a hollow structure with one end open. For example, in Figure 3, the housing 2121 has a cylindrical structure.

[0145] Of course, it is understandable that the shell 212 is not limited to the above structure. The shell 212 may also be other structures. For example, the shell 212 may include a shell body 2121 and two end covers 2122. The shell body 2121 is a hollow structure with openings 2121a on opposite sides. One end cover 2122 corresponds to an opening 2121a of the shell body 2121 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 and the electrolyte. That is, the shell body 2121 is formed with openings 2121a on opposite sides, and the two end covers 2122 are respectively covered on both sides of the shell body 2121 to close the corresponding openings 2121a.

[0146] It should be noted that the electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs, and the electrode assembly 22 may include a positive electrode sheet, a negative electrode sheet, and a separator. The structure of the electrode assembly 22 may be various. For example, the electrode assembly 22 may be a wound structure formed by winding the positive electrode sheet, the separator, and the negative electrode sheet, or a stacked structure formed by stacking the positive electrode sheet, the separator, and the negative electrode sheet. The electrode assembly 22 has a tab, which is used to output or input electrical energy from the electrode assembly 22. The tab of the electrode assembly 22 is a component formed by stacking and connecting the areas on the positive electrode sheet that are not coated with the positive electrode active material layer, or a component formed by stacking and connecting the areas on the negative electrode sheet that are not coated with the negative electrode active material layer.

[0147] The isolating element is an isolating membrane, and the main material of the isolating membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.

[0148] For example, in FIG4 , the electrode assembly 22 is a wound structure formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, and the electrode assembly 22 is cylindrical. Similarly, the number of electrode assemblies 22 housed in the housing 212 can be one or more. For example, in FIG4 , the number of electrode assemblies 22 housed in the housing 212 is one.

[0149] Each electrode assembly 22 has two tabs, each with opposite polarity. These tabs are a first tab 221 and a second tab 222, respectively, which are used to output or input the positive and negative electrodes of the electrode assembly 22. If the first tab 221 is used to output the positive electrode of the electrode assembly 22, then the first tab 221 is formed by stacking and connecting the regions of the positive electrode sheet not coated with the positive electrode active material layer. Correspondingly, the second tab 222 is used to output the negative electrode of the electrode assembly 22. If the first tab 221 is used to output the negative electrode of the electrode assembly 22, then the first tab 221 is formed by stacking and connecting the regions of the negative electrode sheet not coated with the negative electrode active material layer. Correspondingly, the second tab 222 is used to output the positive electrode of the electrode assembly 22.

[0150] For example, in FIG4 , in the first direction X, the first electrode tab 221 and the second electrode tab 222 of the electrode assembly 22 are respectively disposed at both ends of the electrode assembly 22. The first electrode tab 221 is located at the end of the electrode assembly 22 facing the first current collecting member 23. The first electrode tab 221 is connected to the first current collecting member 23 to electrically connect the first electrode lead portion 211 to the electrode assembly 22. The first electrode tab 221 and the first current collecting member 23 can be connected in various ways, such as welding or abutment.

[0151] It should be noted that the shell assembly 21 also includes a second electrode lead-out portion 213 with opposite polarity to the first electrode lead-out portion 211. The second electrode lead-out portion 213 is used to be electrically connected to the second electrode tab 222 of the electrode assembly 22, so that the first electrode lead-out portion 211 and the second electrode lead-out portion 213 can serve as the positive and negative poles of the battery cell 20 respectively.

[0152] It should be noted that, when the first electrode lead-out portion 211 is an electrode terminal insulated and mounted on the end cover 2122 of the housing 212, the second electrode lead-out portion 213 may be the shell 2121 of the housing 212 or the end cover 2122 of the housing 212; when the first electrode lead-out portion 211 is an electrode terminal insulated and mounted on the bottom wall 2121c of the housing 212, the second electrode lead-out portion 213 may be the shell 2121 of the housing 212 or the end cover 2122 of the housing 212; when the first electrode lead-out portion 211 is an electrode terminal insulated and mounted on the bottom wall 2121c of the housing 212, the second electrode lead-out portion 213 may be the shell 2121 of the housing 212 or the end cover 2122 of the housing 212; When the lead-out portion 211 is the bottom wall 2121c of the shell 2121, the second electrode lead-out portion 213 can be an electrode terminal insulated and mounted on the end cover 2122 or the bottom wall 2121c, or it can be an end cover 2122 insulated and connected to the shell 2121; when the first electrode lead-out portion 211 is the end cover 2122 of the outer shell 212, the second electrode lead-out portion 213 can be an electrode terminal insulated and mounted on the end cover 2122 or the bottom wall 2121c, or it can be a shell 2121 insulated and connected to the end cover 2122.

[0153] Optionally, in FIG. 4 , FIG. 5 and FIG. 6 , the first electrode lead-out portion 211 is the bottom wall 2121 c of the shell 2121 , and correspondingly, the second electrode lead-out portion 213 is an electrode terminal insulated and mounted on the bottom wall 2121 c of the shell 2121 . It should be noted that when the first electrode lead-out portion 211 is the bottom wall 2121c of the housing 2121, the first current collecting member 23 serves to electrically connect the first electrode tab 221 and the bottom wall 2121c. The first current collecting member 23 may be a structure disposed between the first electrode tab 221 and the bottom wall 2121c in the first direction X, so that the first current collecting member 23 is directly connected to the bottom wall 2121c. Of course, the first current collecting member 23 may be a structure disposed between the first electrode tab 221 and the end cover 2122 in the first direction X. In this case, the first current collecting member 23 may be connected to the end cover 2122 and then to the side wall 2121b of the housing 2121 through the end cover 2122 to achieve electrical connection between the first current collecting member 23 and the bottom wall 2121c. Similarly, the first current collecting member 23 may also be directly connected to the side wall 2121b of the housing 2121 to achieve electrical connection between the first current collecting member 23 and the bottom wall 2121c. For example, in Figures 5 and 6, the first electrode lead-out portion 211 is the bottom wall 2121c of the shell 2121, the second electrode lead-out portion 213 is an electrode terminal insulated and mounted on the bottom wall 2121c of the shell 2121, and the first current collecting member 23 is arranged between the end cover 2122 and the first pole ear 221 of the electrode assembly 22. The first current collecting member 23 connects the first pole ear 221 and the end cover 2122, and the end cover 2122 is connected to the side wall 2121b of the shell 2121. The side wall 2121b and the bottom wall 2121c (first electrode lead-out portion 211) are an integrally formed structure to achieve the first current collecting member 23 electrically connecting the electrode assembly 22 and the first electrode lead-out portion 211.

[0154] Among them, the first current collecting component 23 plays the role of electrically connecting the first electrode tab 221 of the electrode assembly 22 and the first electrode lead-out portion 211 to realize the input or output of electrical energy of the battery cell 20, so that the first current collecting component 23 can play a transfer role between the electrode assembly 22 and the first electrode lead-out portion 211, which is beneficial to reducing the difficulty of electrical connection between the electrode assembly 22 and the first electrode lead-out portion 211.

[0155] For example, the first current collecting member 23 may be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy.

[0156] The through hole 231 penetrates the first current collecting member 23 along the first direction X. That is, the through hole 231 extends along the first direction X, and the through hole 231 penetrates both sides of the first current collecting member 23 in the first direction X.

[0157] The hole wall surface of the through hole 231 forms a first fold corner 232 along the positive projection in the first direction X, that is, the edge of the projection formed by the through hole 231 in the first direction X forms a first fold corner 232, that is, the hole wall surface of the through hole 231 forms a fold corner structure.

[0158] The portion of the orthographic projection of the through hole 231 along the first direction X is located within the first fold corner 232, that is, the first fold corner 232 is a structure that protrudes away from the through hole 231 toward the edge of the first collecting member 23, so that the angle of the first fold corner 232 on the side facing the through hole 231 is greater than 0 degrees and less than 180 degrees, that is, the angle of the first fold corner 232 on the side facing the through hole 231 can be an acute angle, a right angle or an obtuse angle, so that the portion of the orthographic projection of the through hole 231 along the first direction X is located within the first fold corner 232.

[0159] Optionally, the number of through holes 231 provided on the first current collecting member 23 may be one or more. For example, in FIG7 , one through hole 231 is provided on the first current collecting member 23. Similarly, the number of first folded corners 232 formed on the hole wall surface of the through hole 231 may be one or more. For example, in FIG7 , three first folded corners 232 are formed on the hole wall surface of the through hole 231. The three first folded corners 232 are arranged along the circumference of the through hole 231. Of course, in other embodiments, the number of first folded corners 232 formed on the hole wall surface of the through hole 231 may also be two, four, five, or six.

[0160] In some embodiments, as shown in Figures 4 and 5, the battery cell 20 may further include a second current collecting member 24, which electrically connects the second electrode tab 222 of the electrode assembly 22 and the second electrode lead-out portion 213 to achieve electrical connection between the electrode assembly 22 and the second electrode lead-out portion 213.

[0161] Illustratively, along the first direction X, the second current collecting member 24 is disposed between the bottom wall 2121 c and the electrode assembly 22 , and the second current collecting member 24 connects the second electrode tab 222 and the second electrode lead-out portion 213 .

[0162] It should be noted that the structure and shape of the second current collecting member 24 may be the same as those of the first current collecting member 23 , that is, the second current collecting member 24 may also be provided with corresponding through holes 231 .

[0163] Illustratively, the first electrode tab 221 is the negative electrode of the electrode assembly 22 , and the second electrode tab 222 is the positive electrode of the electrode assembly 22 . Correspondingly, the first electrode lead-out portion 211 is used to output the negative electrode of the battery cell 20 , and the second electrode lead-out portion 213 is used to output the positive electrode of the battery cell 20 .

[0164] By providing a through hole 231 penetrating both sides of the first current collecting member 23 along the first direction X on the first current collecting member 23, a first fold angle 232 is formed on the wall surface of the through hole 231 along the orthographic projection in the first direction X, and a portion of the orthographic projection of the through hole 231 along the first direction X is located within the first fold angle 232, so that the first fold angle 232 formed on the wall surface of the through hole 231 is a fold angle structure that bulges outward away from the through hole 231, so that when the battery cell 20 thermally runs away and releases internal gas, the force acting on the first current collecting member 23 can be 1 generates stress concentration at the first fold corner 232 of the hole wall surface, so as to facilitate tearing of the first current collecting member 23 from the first fold corner 232 of the hole wall surface of the through hole 231, thereby expanding the area of ​​the first current collecting member 23 for the thermal runaway gas to pass through, thereby reducing the obstruction of the first current collecting member 23 to the thermal runaway gas inside the battery cell 20, thereby effectively improving the exhaust smoothness and exhaust efficiency of the battery cell 20, thereby reducing the risk of fire and explosion of the battery cell 20 due to poor pressure relief effect, and is conducive to improving the reliability of the battery cell 20.

[0165] According to some embodiments of the present application, as shown in FIG7 , the angle of the first fold 232 facing the through hole 231 is β, which satisfies 0°<β≤90°. In other words, the first fold 232 facing the through hole 231 is an acute angle or a right angle.

[0166] By setting the angle of the first fold corner 232 facing the through hole 231 to be greater than 0 degrees and less than or equal to 90 degrees, the first fold corner 232 is realized as a fold structure protruding outward away from the through hole 231. At the same time, it can also effectively alleviate the phenomenon that the thermal runaway gas has difficulty tearing the first current collecting component 23 from the first fold corner 232 due to the excessively large angle of the first fold corner 232, which is conducive to improving the tearing effect of the thermal runaway gas on the first current collecting component 23 after stress concentration is generated at the first fold corner 232.

[0167] In some embodiments, the angle of the first corner 232 facing the through hole 231 is β, which satisfies 30°≤β≤90°.

[0168] Exemplarily, the angle of the first corner 232 facing the side of the through hole 231 can be 30°, 32°, 35°, 38°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 72°, 75°, 80°, 85° or 90°, etc.

[0169] By setting the angle of the first fold corner 232 facing the through hole 231 to 30 to 90 degrees, the difficulty in processing the through hole 231 caused by the first fold corner 232 being too small can be alleviated, thereby reducing the manufacturing difficulty and manufacturing cost of the first current collecting member 23.

[0170] According to some embodiments of the present application, as shown in FIG. 7 , a plurality of first folded corners 232 are formed on the wall surface of the through hole 231 , and the plurality of first folded corners 232 are sequentially arranged along the circumference of the through hole 231 .

[0171] Among them, the multiple first corners 232 are arranged in sequence along the circumference of the through hole 231, that is, the multiple first corners 232 formed on the hole wall surface of the through hole 231 are arranged in sequence along the circumferential direction of the hole wall surface of the through hole 231.

[0172] It should be noted that the circumferential direction of the through hole 231 is the circumferential direction of the hole wall surface of the through hole 231 .

[0173] For example, in FIG7 , the wall surface of the through hole 231 is formed with three first folded corners 232, which are arranged in sequence along the circumference of the through hole 231. Of course, the first current collecting member 23 can also have other structures. Referring to FIG8 , FIG8 is a schematic structural diagram of the first current collecting member 23 provided in some other embodiments of the present application. The wall surface of the through hole 231 is formed with four first folded corners 232 arranged along the circumference of the through hole 231. It should be noted that in other embodiments, the number of first folded corners 232 formed on the wall surface of the through hole 231 can also be five, six, seven, eight, or nine, etc.

[0174] By forming multiple first fold corners 232 on the wall surface of the through hole 231, and the multiple first fold corners 232 are arranged in sequence along the circumference of the through hole 231, the thermal runaway gas can tear the first collecting member 23 from the multiple first fold corners 232 after generating stress concentration at the multiple first fold corners 232 on the wall surface of the through hole 231, so that the first collecting member 23 can be torn from multiple positions, which is conducive to further expanding the area of ​​the first collecting member 23 for the thermal runaway gas to pass through, so as to further reduce the obstruction of the first collecting member 23 to the thermal runaway gas inside the battery cell 20, thereby effectively improving the exhaust smoothness and exhaust efficiency of the battery cell 20.

[0175] According to some embodiments of the present application, please continue to refer to FIG. 7 . Along the circumference of the through hole 231 , the hole wall of the through hole 231 includes a plurality of first wall surfaces 2311 , and a first angle 232 is formed between each two adjacent first wall surfaces 2311 .

[0176] Among them, a first fold angle 232 is formed between each two adjacent first wall surfaces 2311, that is, the angle between each two adjacent first avoidances is less than 180 degrees, that is, the cross-section of the through hole 231 perpendicular to the first direction X is a polygon. For example, in Figure 7, the cross-section of the through hole 231 perpendicular to the first direction X is a triangle, and in Figure 8, the cross-section of the through hole 231 perpendicular to the first direction X is a rectangle. Of course, in other embodiments, the cross-section of the through hole 231 perpendicular to the first direction X may also be a pentagon, a hexagon or a heptagon, etc.

[0177] By setting the hole wall surface of the through hole 231 to have multiple first wall surfaces 2311 arranged along the circumference of the through hole 231, and forming a first fold angle 232 between each two adjacent first wall surfaces 2311, the orthographic projection of the through hole 231 along the first direction X is a polygonal structure, so that the hole wall surface of the through hole 231 is formed with multiple first fold angles 232 arranged in sequence along the circumference of the through hole 231. The structure is simple and easy to implement.

[0178] According to some embodiments of the present application, referring to FIG. 7 and FIG. 8 , the angles of the plurality of first corners 232 are all the same.

[0179] The angles of the multiple first corners 232 are the same, that is, the angles between each two adjacent first wall surfaces 2311 in the multiple first wall surfaces 2311 are the same, that is, the cross section of the through hole 231 perpendicular to the first direction X is a regular polygon.

[0180] For example, in FIG7 , the cross section of the through hole 231 perpendicular to the first direction X is an equilateral triangle, and in FIG8 , the cross section of the through hole 231 perpendicular to the first direction X is a square. Of course, in other embodiments, the cross section of the through hole 231 perpendicular to the first direction X may also be a regular pentagon, a regular hexagon, a regular heptagon or a regular octagon, etc.

[0181] By setting the multiple first corners 232 to have the same angle, the angles between each adjacent two first wall surfaces 2311 in the multiple first wall surfaces 2311 of the hole wall of the through hole 231 are the same, so that the positive projection of the through hole 231 along the first direction X is a regular polygon structure. On the one hand, this facilitates the manufacturing and processing of the through hole 231, which is beneficial to reducing the manufacturing difficulty of the first current collecting component 23. On the other hand, the force acting to tear the first current collecting component 23 from the multiple first corners 232 is the same, so that the thermal runaway gas can tear the first current collecting component 23 from the multiple first corners 232.

[0182] In some embodiments, as shown in FIG. 7 , the first current collecting member 23 is a disc-shaped structure, and the central axis of the first current collecting member 23 coincides with the central axis of the through hole 231 .

[0183] The first current collecting member 23 is a disc-shaped structure, and the thickness direction of the first current collecting member 23 is the first direction X.

[0184] The central axis of the first current collecting member 23 coincides with the central axis of the through hole 231 . That is, the center of the cross section of the through hole 231 perpendicular to the first direction X is located on the central axis of the first current collecting member 23 .

[0185] By setting the central axis of the first current collecting member 23 to coincide with the central axis of the through hole 231, the through hole 231 is located at the center of the first current collecting member 23. Therefore, when the first current collecting member 23 is electrically connected to the electrode assembly 22 and the first electrode lead-out portion 211, the area of ​​the first current collecting member 23 surrounding the outside of the through hole 231 can be electrically connected to the electrode assembly 22 and the first electrode lead-out portion 211. There is no need to re-position the first current collecting member 23 to avoid the through hole 231, which helps to reduce the difficulty of assembling the first current collecting member 23 into the housing assembly 21, thereby improving the assembly efficiency of the battery cell 20.

[0186] According to some embodiments of the present application, as shown in FIG. 7 and FIG. 8 , along the circumference of the through hole 231 , every two adjacent first wall surfaces 2311 are connected via a chamfered surface 2312 .

[0187] Among them, each adjacent two first wall surfaces 2311 are connected by a chamfered surface 2312, that is, the connection position between each adjacent two first wall surfaces 2311 is a circular arc transition structure, so that the connection position between each adjacent two first wall surfaces 2311 forms a chamfered surface 2312.

[0188] Connecting two adjacent first walls 2311 through the chamfered surface 2312 can help reduce the difficulty of machining the through hole 231 on the first current collecting member 23 and reduce the requirements on equipment for machining the through hole 231 on the first current collecting member 23 .

[0189] According to some embodiments of the present application, referring to FIG. 7 and FIG. 8 , the orthographic projection of the through hole 231 along the first direction X is a polygon.

[0190] The orthographic projection of the through hole 231 along the first direction X is a polygon, that is, the cross section of the through hole 231 perpendicular to the first direction X is a polygonal structure. For example, the orthographic projection of the through hole 231 along the first direction X can be a triangle, a rectangle, a pentagon, a hexagon, or a heptagon.

[0191] By setting the through hole 231 to be a polygonal structure with a positive projection along the first direction X, a first fold angle 232 is formed between every two adjacent sides of the polygon, so that the hole wall surface of the through hole 231 is formed with multiple first fold angles 232 arranged in sequence along the circumference of the through hole 231. The structure is simple and easy to implement.

[0192] In some embodiments, referring to FIG. 7 and FIG. 8 , the orthographic projection of the through hole 231 along the first direction X is a regular polygon.

[0193] The orthographic projection of the through hole 231 along the first direction X is a regular polygon, that is, multiple internal angles of the cross section of the through hole 231 perpendicular to the first direction X are equal.

[0194] For example, the orthographic projection of the through hole 231 along the first direction X may be an equilateral triangle, a square, a regular pentagon, a regular hexagon, or the like.

[0195] By setting the through hole 231 to have a regular polygonal structure as its positive projection along the first direction X, the angles of the multiple first corners 232 formed on the hole wall of the through hole 231 are all the same, which, on the one hand, facilitates the manufacturing and processing of the through hole 231, and helps to reduce the manufacturing difficulty of the first current collecting component 23. On the other hand, the force acting to tear the first current collecting component 23 from the multiple first corners 232 is the same, so that the thermal runaway gas can tear the first current collecting component 23 from the multiple first corners 232.

[0196] In some embodiments, referring to FIG. 7 and FIG. 8 , the orthographic projection of the through hole 231 along the first direction X is a triangle or a rectangle.

[0197] In FIG. 7 , the orthographic projection of the through hole 231 along the first direction X is an equilateral triangle. Of course, the shape of the through hole 231 is not limited thereto. In other embodiments, the orthographic projection of the through hole 231 along the first direction X may also be an isosceles triangle, a right triangle, etc.

[0198] In FIG8 , the orthographic projection of the through hole 231 along the first direction X is a square. Of course, the shape of the through hole 231 is not limited thereto. In other embodiments, the orthographic projection of the through hole 231 along the first direction X may also be a rectangle.

[0199] By setting the through hole 231 to have a positive projection along the first direction X as a triangle or a rectangle, so that the through hole 231 is a triangular hole or a rectangular hole, on the one hand, it is convenient to process the through hole 231 on the first collecting component 23, which is beneficial to reduce the difficulty of processing the through hole 231, and on the other hand, it can effectively control the angle of the first fold angle 232 to alleviate the phenomenon that the angle of the first fold angle 232 is too large or too small.

[0200] According to some embodiments of the present application, referring to Figures 9 and 10, Figure 9 is a schematic structural diagram of a first current collecting member 23 provided in some further embodiments of the present application, and Figure 10 is a schematic structural diagram of a first current collecting member 23 provided in some other embodiments of the present application. A plurality of angles are formed on the wall surface of the through hole 231. Along the circumference of the through hole 231, the wall surface of the through hole 231 includes a plurality of first wall surfaces 2311, with an angle formed between each two adjacent first wall surfaces 2311. The plurality of angles include a first angle 232 and a second angle 233, with the angle of the second angle 233 facing the side of the through hole 231 being greater than 180°.

[0201] Among them, a fold angle is formed between each two adjacent first walls 2311, that is, among the multiple first walls 2311 of the hole wall surface of the through hole 231, each two adjacent first walls 2311 are set at an angle to form a fold angle between each two adjacent first walls 2311.

[0202] The multiple angles include a first angle 232 and a second angle 233, and the angle of the second angle 233 facing the side of the through hole 231 is greater than 180°. That is, among the multiple angles formed on the wall surface of the through hole 231, some of the angles are the first angle 232, that is, the angle of some of the angles facing the side of the through hole 231 is less than 180 degrees, so that this part of the angle is a angle structure protruding outward away from the through hole 231, and the other part of the angle is the second angle 233, that is, the angle of some of the angles facing the side of the through hole 231 is greater than 180 degrees, so that this part of the angle is a angle structure protruding inward facing the through hole 231.

[0203] It should be noted that the number of first folded corners 232 formed on the hole wall surface of the through hole 231 can be one or more, and similarly, the number of second folded corners 233 formed on the hole wall surface of the through hole 231 can be one or more. For example, in FIG9 , the hole wall surface of the through hole 231 is formed with four first folded corners 232 and four second folded corners 233, and the first folded corners 232 and the second folded corners 233 are arranged alternately along the circumference of the through hole 231. In FIG10 , the hole wall surface of the through hole 231 is formed with five first folded corners 232 and five second folded corners 233, and the first folded corners 232 and the second folded corners 233 are arranged alternately along the circumference of the through hole 231. Of course, in other embodiments, the number of first folded corners 232 and second folded corners 233 can also be other numbers, for example, the number of first folded corners 232 and second folded corners 233 can be three, six, or seven, etc. Similarly, the number of first folded corners 232 and second folded corners 233 can also be unequal.

[0204] A second fold corner 233 is formed on the wall surface of the through hole 231, and the angle of the second fold corner 233 facing the side of the through hole 231 is greater than 180 degrees, so that the second fold corner 233 is a fold structure protruding inward toward the through hole 231, so that the angle of the first fold corner 232 can be adjusted through the second fold corner 233, so as to reduce the angle of the first fold corner 232, making it easier for the thermal runaway gas to tear the first collecting component 23 from the first fold corner 232.

[0205] According to some embodiments of the present application, as shown in Figures 9 and 10, the multiple fold corners include multiple first fold corners 232 and multiple second fold corners 233. Along the circumference of the through hole 231, the first fold corners 232 and the second fold corners 233 are alternately arranged.

[0206] The first folded corners 232 and the second folded corners 233 are alternately arranged along the circumference of the through hole 231 . That is, a first folded corner 232 is provided between every two adjacent second folded corners 233 along the circumference of the through hole 231 .

[0207] For example, in FIG9 , the hole wall surface of the through hole 231 is formed with four first folded corners 232 and four second folded corners 233 . In FIG10 , the hole wall surface of the through hole 231 is formed with five first folded corners 232 and five second folded corners 233 .

[0208] By setting the first fold corner 232 and the second fold corner 233 to be arranged alternately in the circumferential direction of the through hole 231, a first fold corner 232 is formed between each two adjacent second fold corners 233, thereby facilitating the adjustment of the angle size of the first fold corner 232 located between the two second fold corners 233 through the two adjacent second fold corners 233.

[0209] According to some embodiments of the present application, referring to FIG. 9 and FIG. 10 , the angles of the plurality of first fold corners 232 are all the same, and the angles of the plurality of second fold corners 233 are all the same.

[0210] By setting multiple first fold angles 232 to have the same angle, and setting multiple second fold angles 233 to have the same angle, the positive projection of the through hole 231 along the first direction X is realized to have a regular shape. This, on the one hand, facilitates the manufacturing and processing of the through hole 231, which is beneficial to reducing the manufacturing difficulty of the first current collecting component 23. On the other hand, the force acting to tear the first current collecting component 23 from the multiple first fold angles 232 is the same, so that the thermal runaway gas can tear the first current collecting component 23 from the multiple first fold angles 232.

[0211] In some embodiments, the first current collecting member 23 is a disc-shaped structure, and the central axis of the first current collecting member 23 coincides with the central axis of the through hole 231 .

[0212] The first current collecting member 23 is a disc-shaped structure, and the thickness direction of the first current collecting member 23 is the first direction X.

[0213] The central axis of the first current collecting member 23 coincides with the central axis of the through hole 231 . That is, the center of the cross section of the through hole 231 perpendicular to the first direction X is located on the central axis of the first current collecting member 23 .

[0214] By setting the central axis of the first current collecting member 23 to coincide with the central axis of the through hole 231, the through hole 231 is located at the center of the first current collecting member 23. Therefore, when the first current collecting member 23 is electrically connected to the electrode assembly 22 and the first electrode lead-out portion 211, the area of ​​the first current collecting member 23 surrounding the outside of the through hole 231 can be electrically connected to the electrode assembly 22 and the first electrode lead-out portion 211. There is no need to re-position the first current collecting member 23 to avoid the through hole 231, which helps to reduce the difficulty of assembling the first current collecting member 23 into the housing assembly 21, thereby improving the assembly efficiency of the battery cell 20.

[0215] In some embodiments, along the circumference of the through hole 231 , every two adjacent first wall surfaces 2311 are connected by a chamfered surface 2312 .

[0216] Among them, each adjacent two first wall surfaces 2311 are connected by a chamfered surface 2312, that is, the connection position between each adjacent two first wall surfaces 2311 is a circular arc transition structure, so that the connection position between each adjacent two first wall surfaces 2311 forms a chamfered surface 2312.

[0217] Connecting two adjacent first walls 2311 through the chamfered surface 2312 can help reduce the difficulty of machining the through hole 231 on the first current collecting member 23 and reduce the requirements on equipment for machining the through hole 231 on the first current collecting member 23 .

[0218] According to some embodiments of the present application, as shown in Figures 4, 5 and 6, the electrode assembly 22 has a central channel 223 extending along the first direction X, and at least a portion of the orthographic projection of the central channel 223 along the first direction X is located within the through hole 231.

[0219] The central through hole 231 passes through both ends of the electrode assembly 22 along the first direction X. At least a portion of the orthographic projection of the central channel 223 along the first direction X is located within the through hole 231 , that is, the orthographic projection of the through hole 231 along the first direction X covers at least a portion of the central through hole 231 .

[0220] For example, in FIG. 5 and FIG. 6 , the orthographic projection of the through hole 231 along the first direction X is a regular shape, and the central axis of the through hole 231 coincides with the central axis of the center through hole 231 .

[0221] By setting at least a portion of the positive projection of the central channel 223 of the electrode assembly 22 along the first direction X to be located within the through hole 231 of the first current collecting member 23, the through hole 231 and the central channel 223 are overlapping structures in the first direction X, so that the thermal runaway gas generated in the central channel 223 of the electrode assembly 22 can directly act on the first corner 232 of the hole wall of the through hole 231, thereby making it easier to tear the first current collecting member 23 from the first corner 232.

[0222] 3 and 4 , the battery cell 20 is cylindrical, and the axis of the battery cell 20 is the same as the first direction X. That is, the battery cell 20 is a cylindrical structure, and the central axis of the battery cell 20 extends along the first direction X.

[0223] By configuring the battery cell 20 as a cylindrical structure, the battery cell 20 has the advantages of high capacity, long cycle life, and wide operating temperature range.

[0224] According to some embodiments of the present application, as shown in Figures 3, 4, 5 and 6, the housing assembly 21 includes a housing 212, the electrode assembly 22 is accommodated in the housing 212, and at least a portion of the housing 212 forms a first electrode lead-out portion 211.

[0225] Among them, the shell 212 serves to accommodate the electrode assembly 22, and at least part of the shell 212 forms the first electrode lead-out portion 211, that is, a part of the shell 212 serves as the first electrode lead-out portion 211 to output or input electrical energy of the battery cell 20. The first electrode lead-out portion 211 can be the end cover 2122 of the shell 212, or it can be the shell 2121 of the shell 212.

[0226] The shell assembly 21 is provided with a shell 212. By using at least a portion of the shell 212 as the first electrode lead-out portion 211, the electrode assembly 22 is connected to the shell 212 through the first current collecting member 23, so that the input or output of electrical energy of the battery cell 20 can be realized. The structure is simple and easy to assemble.

[0227] According to some embodiments of the present application, as shown in Figures 3, 4, 5, and 6, the housing 212 may include a shell 2121 and an end cap 2122. The shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c. The side wall 2121b is disposed around the bottom wall 2121c. One end of the side wall 2121b is connected to the bottom wall 2121c, and the other end of the side wall 2121b forms an opening 2121a opposite the bottom wall 2121c. The side wall 2121b and the bottom wall 2121c together define a housing cavity for accommodating the electrode assembly 22. The end cap 2122 closes the opening 2121a. The bottom wall 2121c serves as the first electrode lead portion 211.

[0228] Among them, the shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c, that is, the shell 2121 is made using an integral molding process, such as stamping, casting or extrusion molding, that is, the side wall 2121b and the bottom wall 2121c of the shell 2121 are an integral structure.

[0229] The bottom wall 2121c is the first electrode lead portion 211. That is, the bottom wall 2121c of the shell 2121 of the outer shell 212 is used to output or input electrical energy from the battery cell 20. It should be noted that when the first electrode lead portion 211 is the bottom wall 2121c of the shell 2121, the second electrode lead portion 213 can be an electrode terminal insulated and mounted on the bottom wall 2121c or the end cover 2122, or can be an end cover 2122 insulated and connected to the shell 2121. For example, in Figures 4 and 5, the first electrode lead portion 211 is the bottom wall 2121c, and the second electrode lead portion 213 is an electrode terminal insulated and mounted on the bottom wall 2121c.

[0230] By using the bottom wall 2121c of the shell 2121 as the first electrode lead-out portion 211 for outputting or inputting electrical energy of the battery cell 20, the first electrode lead-out portion 211 can be kept away from the end cover 2122, thereby effectively alleviating the phenomenon that the force generated by the pulling or twisting of the first electrode lead-out portion 211 by components such as the busbar component connected to the first electrode lead-out portion 211 acts between the end cover 2122 and the shell 2121, thereby reducing the risk of connection failure between the end cover 2122 and the shell 2121, which is conducive to further reducing the risk of leakage of the battery cell 20 during use.

[0231] According to some embodiments of the present application, in an embodiment where the first electrode lead-out portion 211 is a bottom wall 2121c, as shown in Figures 4, 5, and 6, the first current collecting member 23 is disposed between the end cap 2122 and the electrode assembly 22 along the first direction X. The first current collecting member 23 is connected to the end cap 2122, and the end cap 2122 is electrically connected to the side wall 2121b, thereby electrically connecting the first current collecting member 23 and the bottom wall 2121c.

[0232] Among them, along the first direction X, the first current collecting member 23 and the second current collecting member 24 are respectively located at both ends of the electrode assembly 22, the first current collecting member 23 is located between the end cover 2122 and the first electrode tab 221, and the second current collecting member 24 is located between the bottom wall 2121c and the second electrode tab 222, and the second current collecting member 24 connects the second electrode tab 222 and the second electrode lead-out portion 213.

[0233] The first current collecting member 23 is connected to the end cover 2122, and the end cover 2122 is electrically connected to the side wall 2121b. That is, the first current collecting member 23 is directly connected to the end cover 2122, and the end cover 2122 is electrically connected to the side wall 2121b, so that the first current collecting member 23 is indirectly electrically connected to the bottom wall 2121c through the end cover 2122 and the side wall 2121b in sequence.

[0234] Optionally, the first current collecting member 23 and the end cover 2122 may be connected by various structures, such as welding, clamping or bonding.

[0235] In some embodiments, as shown in FIG6 , the end cap 2122 has a protrusion 2122a on the side facing the electrode assembly 22, and the protrusion 2122a is welded to the first current collecting member 23. Exemplarily, the protrusion 2122a is formed by a stamping process on the side of the end cap 2122 facing the electrode assembly 22. Of course, in other embodiments, the protrusion 2122a can also be formed by a casting process or other processes.

[0236] It should be noted that the structure of the battery cell 20 is not limited to this. In a structure where the first current collecting member 23 is disposed between the end cap 2122 and the first electrode tab 221, the first current collecting member 23 may also be connected to the side wall 2121b to electrically connect the first current collecting member 23 and the bottom wall 2121c. In other words, the outer circumferential surface of the first current collecting member 23 is interconnected with the inner surface of the side wall 2121b, thereby achieving an indirect electrical connection to the bottom wall 2121c through the side wall 2121b. In this embodiment, the end cap 2122 and the side wall 2121b may be electrically connected or insulated.

[0237] By arranging the first current collecting member 23 between the end cover 2122 and the electrode assembly 22 in the first direction X, and the first current collecting member 23 can be indirectly electrically connected to the shell 2121 through the end cover 2122 or the first current collecting member 23 can be directly connected to the side wall 2121b of the shell 2121, so as to achieve electrical connection between the first current collecting member 23 and the bottom wall 2121c serving as the first electrode lead-out portion 211, the structure is simple and easy to implement.

[0238] Of course, in the embodiment where the bottom wall 2121c is the first electrode lead portion 211, the battery cell 20 may also have other structures. For example, along the first direction X, the first current collecting member 23 is disposed between the bottom wall 2121c and the electrode assembly 22, and the first current collecting member 23 is connected to the bottom wall 2121c. In other words, the first current collecting member 23 is located between the bottom wall 2121c and the first electrode tab 221 of the electrode assembly 22 in the first direction X, so that the first current collecting member 23 can directly connect the bottom wall 2121c and the first electrode tab 221. Correspondingly, the second current collecting member 24 may be disposed between the end cap 2122 and the second electrode tab 222 of the electrode assembly 22. In this embodiment, the second electrode lead portion 213 may be an electrode terminal insulatedly mounted on the end cap 2122, or an end cap 2122 insulatedly connected to the side wall 2121b of the housing 2121.

[0239] By arranging the first current collecting member 23 between the bottom wall 2121c and the electrode assembly 22 in the first direction X, the first current collecting member 23 can be directly connected to the bottom wall 2121c, so as to achieve electrical connection between the first current collecting member 23 and the bottom wall 2121c serving as the first electrode lead-out portion 211, which has a simple structure and is easy to assemble.

[0240] According to some embodiments of the present application, the structure of the battery cell 20 is not limited to this. The battery cell 20 may also have other structures. For example, the outer shell 212 may include a shell 2121 and an end cap 2122. The shell 2121 has an interior formed with an accommodating cavity having an opening 2121a, and the electrode assembly 22 is accommodated in the accommodating cavity. The end cap 2122 closes the opening 2121a and serves as the first electrode lead portion 211.

[0241] The end cap 2122 is the first electrode lead portion 211. In other words, the end cap 2122 of the outer shell 212 is used to output or input electrical energy from the battery cell 20. It should be noted that when the first electrode lead portion 211 is the end cap 2122 of the outer shell 212, the second electrode lead portion 213 can be an electrode terminal insulated and mounted on the bottom wall 2121c or the end cap 2122, or can be the outer shell 2121 insulated and connected to the end cap 2122.

[0242] By using the end cover 2122 of the outer shell 212 as the first electrode lead-out portion 211 for outputting or inputting electrical energy of the battery cell 20, it is helpful to reduce the assembly difficulty between the first current collecting member 23 and the first electrode lead-out portion 211 and between the first current collecting member 23 and the electrode assembly 22, thereby improving the production efficiency of the battery cell 20.

[0243] In the embodiment where the first electrode lead portion 211 is an end cap 2122, the first current collecting member 23 is disposed between the end cap 2122 and the electrode assembly 22 along the first direction X, and the first current collecting member 23 is connected to the end cap 2122. In other words, the first current collecting member 23 is located between the end cap 2122 and the first electrode tab 221 of the electrode assembly 22 in the first direction X, enabling the first current collecting member 23 to directly connect the end cap 2122 and the first electrode tab 221 of the electrode assembly 22. Correspondingly, the second current collecting member 24 is located between the bottom wall 2121c and the second electrode tab 222 of the electrode assembly 22 in the first direction X. In this embodiment, the second electrode lead portion 213 can be an electrode terminal insulatedly mounted on the bottom wall 2121c of the housing 2121, or it can be the housing 2121 insulatedly connected to the end cap 2122.

[0244] By arranging the first current collecting member 23 between the end cover 2122 and the electrode assembly 22 in the first direction X, the first current collecting member 23 can be directly connected to the end cover 2122, so as to realize electrical connection between the first current collecting member 23 and the end cover 2122 serving as the first electrode lead-out portion 211, which has a simple structure and is easy to assemble.

[0245] According to some embodiments of the present application, the battery cell 20 may also have other structures. For example, the housing assembly 21 further includes a housing 212, and the electrode assembly 22 is accommodated in the housing 212. The first electrode lead-out portion 211 is insulated and mounted on the housing 212. Along the first direction X, at least a portion of the first current collecting member 23 is disposed between the first electrode lead-out portion 211 and the electrode assembly 22, and the first current collecting member 23 is connected to the first electrode lead-out portion 211.

[0246] Among them, the first electrode lead-out portion 211 is insulated and installed on the outer shell 212, that is, the first electrode lead-out portion 211 is an electrode terminal insulated and installed on the outer shell 212. The first electrode lead-out portion 211 can be insulated and installed on the end cover 2122 of the outer shell 212, or can be insulated and installed on the bottom wall 2121c of the shell 2121.

[0247] The shell assembly 21 is also provided with a shell 212. By insulating and installing the first electrode lead-out portion 211 on the shell 212, the first electrode lead-out portion 211 can realize the input or output of electrical energy of the battery cell 20. The battery cell 20 adopting this structure can reduce the risk of short circuit between the first electrode lead-out portion 211 and the shell 212, so as to improve the reliability of the battery cell 20.

[0248] In an embodiment where the first electrode lead portion 211 is an electrode terminal insulated and mounted on the housing 212, the housing 212 may include a shell 2121 and an end cap 2122. The shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c. The side wall 2121b is disposed around the bottom wall 2121c. One end of the side wall 2121b is connected to the bottom wall 2121c, and the other end of the side wall 2121b forms an opening 2121a opposite to the bottom wall 2121c. The side wall 2121b and the bottom wall 2121c together define a housing cavity for accommodating the electrode assembly 22. The end cap 2122 closes the opening 2121a. The first electrode lead portion 211 is insulated and mounted on the end cap 2122.

[0249] Among them, the shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c, that is, the shell 2121 is made using an integral molding process, such as stamping, casting or extrusion molding, that is, the side wall 2121b and the bottom wall 2121c of the shell 2121 are an integral structure.

[0250] The first electrode lead-out portion 211 is insulated and mounted on the end cap 2122. That is, the first electrode lead-out portion 211 is an electrode terminal insulated and mounted on the end cap 2122. Correspondingly, the first current collecting member 23 is located between the end cap 2122 and the first electrode tab 221 of the electrode assembly 22 in the first direction X. In this embodiment, the second electrode lead-out portion 213 may be the bottom wall 2121c of the housing 2121. That is, the second current collecting member 24 is located between the bottom wall 2121c and the second electrode tab 221 of the electrode assembly 22 in the first direction X. Between the electrode tabs 222, the second current collecting member 24 is directly connected to the bottom wall 2121c and the second electrode tab 222 of the electrode assembly 22. Of course, the second electrode lead-out portion 213 can also be the end cover 2122 of the outer shell 212, that is, the second current collecting member 24 is located between the bottom wall 2121c and the second electrode tab 222 of the electrode assembly 22 in the first direction X. The second current collecting member 24 can be connected to the bottom wall 2121c or to the side wall 2121b to achieve indirect electrical connection between the second current collecting member 24 and the end cover 2122.

[0251] Of course, in some embodiments, the first electrode lead portion 211 may also be insulated and installed on the bottom wall 2121 c. That is to say, the first electrode lead-out portion 211 is an electrode terminal insulated and mounted on the bottom wall 2121c. Correspondingly, the first current collecting member 23 is located between the bottom wall 2121c and the first electrode tab 221 of the electrode assembly 22 in the first direction X. In this embodiment, the second electrode lead-out portion 213 can be the end cover 2122 of the shell 2121, that is, the second current collecting member 24 is located between the end cover 2122 and the second electrode tab 222 of the electrode assembly 22 in the first direction X. The second current collecting member 24 directly connects the end cover 2122 and the second electrode tab 222 of the electrode assembly 22. Of course, the second electrode lead-out portion 213 can also be the bottom wall 2121c of the shell 2121, that is, the second current collecting member 24 is located between the end cover 2122 and the second electrode tab 222 of the electrode assembly 22 in the first direction X. The second current collecting member 24 can be connected to the end cover 2122 or to the side wall 2121b to achieve indirect electrical connection between the second current collecting member 24 and the bottom wall 2121c.

[0252] By insulating and mounting the first electrode lead-out portion 211 on the end cover 2122, the first electrode lead-out portion 211 can output or input electrical energy to the battery cell 20. The battery cell 20 adopting this structure facilitates the insulated assembly of the first electrode lead-out portion 211 on the outer shell 212, which is beneficial to reducing the difficulty of assembly between the first electrode lead-out portion 211 and the outer shell 212, thereby improving the production efficiency of the battery cell 20. Similarly, by insulating and mounting the first electrode lead-out portion 211 on the bottom wall 2121c of the shell 2121, the first electrode lead-out portion 211 can output or input electrical energy to or from the battery cell 20. The battery cell 20 with this structure keeps the first electrode lead-out portion 211 away from the end cover 2122, thereby alleviating the phenomenon in which the force generated by the pulling or twisting of the bottom wall 2121c by the first electrode lead-out portion 211 acts on the end cover 2122, thereby reducing the risk of connection failure between the end cover 2122 and the shell 2121, and further helping to reduce the risk of leakage of the battery cell 20 during use.

[0253] According to some embodiments of the present application, as shown in Figures 4, 5, and 6, the battery cell 20 may further include a pressure relief mechanism 25. The pressure relief mechanism 25 is disposed on the housing 212 and is configured to release the internal pressure of the battery cell 20. The pressure relief mechanism 25 is disposed opposite to the through hole 231 along the first direction X.

[0254] The pressure relief mechanism 25 is positioned opposite the through-hole 231 along the first direction X. That is, the pressure relief mechanism 25 and the first current collecting member 23 are located at the same end of the electrode assembly 22 in the first direction X. For example, if the first current collecting member 23 is positioned between the end cap 2122 and the electrode assembly 22 in the first direction X, the pressure relief mechanism 25 is positioned on the end cap 2122. If the first current collecting member 23 is positioned between the bottom wall 2121c of the housing 2121 and the electrode assembly 22 in the first direction X, the pressure relief mechanism 25 is positioned on the bottom wall 2121c. For example, in Figures 5 and 6 , the first current collecting member 23 is positioned between the end cap 2122 and the electrode assembly 22 in the first direction X, and the pressure relief mechanism 25 is correspondingly positioned on the end cap 2122.

[0255] Optionally, the pressure relief mechanism 25 and the end cap 2122 may be integrally formed or separately provided. For example, in FIG6 , the pressure relief mechanism 25 and the end cap 2122 are integrally formed, and the pressure relief mechanism 25 is the region of the end cap 2122 where the notched groove is provided. Of course, in other embodiments, the pressure relief mechanism 25 and the end cap 2122 may also be separate structures, and the pressure relief mechanism 25 may be connected to the end cap 2122 by welding or other means. Accordingly, the pressure relief mechanism 25 may be a pressure relief component such as an explosion-proof valve, explosion-proof disk, air valve, pressure relief valve, or safety valve.

[0256] By setting the pressure relief mechanism 25 on the shell 212 and making the pressure relief mechanism 25 and the through hole 231 relatively arranged along the first direction X, on the one hand, the internal pressure of the battery cell 20 can be released through the pressure relief mechanism 25 to reduce the risk of fire and explosion of the battery cell 20. On the other hand, after the first current collecting member 23 is torn by the thermal runaway gas from the first corner 232, the thermal runaway gas can be directly discharged from the pressure relief mechanism 25, which can further reduce the phenomenon that the first current collecting member 23 blocks the thermal runaway gas from being discharged from the interior of the battery cell 20 through the pressure relief mechanism 25.

[0257] According to some embodiments of the present application, the present application further provides a battery 100 , which includes the battery cell 20 of any of the above solutions.

[0258] In some embodiments, as shown in FIG. 2 , the battery 100 may further include a box 10 for accommodating the battery cells 20 .

[0259] The housing 10 is used to provide an assembly space for the battery cells 20. The housing 10 can adopt various structures. For example, the housing 10 can include a first housing body 11 and a second housing body 12. The first housing body 11 and the second housing body 12 cover each other and together define an assembly space for accommodating the battery cells 20.

[0260] Optionally, the second box body 12 can be a hollow structure with one end open, and the first box body 11 can be a plate-like structure, and the first box body 11 covers the open side of the second box body 12, so that the first box body 11 and the second box body 12 jointly define an assembly space; the first box body 11 and the second box body 12 can also be hollow structures with one side open, and the open side of the first box body 11 covers the open side of the second box body 12.

[0261] Of course, the box body 10 formed by the first box body 11 and the second box body 12 can be in various shapes, such as a cylinder, a cube or a cuboid, etc. For example, in FIG2 , the box body 10 is in the shape of a cuboid.

[0262] Optionally, the battery cell 20 housed in the housing 10 may be one or more. For example, in FIG2 , the battery 100 may include multiple battery cells 20, which may be connected in series, in parallel, or in a hybrid configuration. A hybrid configuration refers to a configuration in which multiple battery cells 20 are connected in both series and parallel. Multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid configuration, and then the entire structure formed by the multiple battery cells 20 is housed in the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid configuration to form a battery module, which is then connected in series, in parallel, or in a hybrid configuration to form a single structure and housed in the housing 10.

[0263] In some embodiments, the battery 100 may further include other structures. For example, the battery 100 may further include a busbar component, which is used to connect the multiple battery cells 20 to achieve electrical connection between the multiple battery cells 20 .

[0264] According to some embodiments of the present application, the present application further provides an electrical device, which includes the battery cell 20 of any of the above solutions, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0265] The electrical device may be any of the aforementioned devices or systems using the battery cell 20 .

[0266] It should be noted that when the battery cell 20 is installed on the electrical device, the battery cell 20 can be installed directly on the electrical device, or the battery cell 20 can be first assembled into the housing 10 and then assembled to the electrical device through the housing 10. For example, taking the vehicle 1000 as an example of the electrical device, the battery cell 20 can be first assembled into the housing 10 to form the battery 100, and then the battery 100 is assembled on the vehicle 1000. The battery cell 20 can also be directly assembled on the vehicle 1000. In other words, the housing 10 can serve as part of the electrical device. Taking the vehicle 1000 as an example of the electrical device, the housing 10 can serve as part of the chassis structure of the vehicle 1000. For example, a portion of the housing 10 can serve as at least a portion of the floor of the vehicle 1000, or a portion of the housing 10 can serve as at least a portion of the crossbeam and longitudinal beam of the vehicle 1000. Similarly, the number of battery cells 20 provided on the electrical device may be one or more, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection.

[0267] According to some embodiments of the present application, referring to FIG. 3 to FIG. 8 , the present application provides a battery cell 20 , which includes a housing assembly 21 , an electrode assembly 22 , a first current collecting member 23 , and a pressure relief mechanism 25 . The shell assembly 21 includes a shell 212 and a first electrode lead-out portion 211 for inputting or outputting electrical energy. The shell 212 is cylindrical, and the electrode assembly 22 is accommodated in the shell 212. The shell 212 includes a shell 2121 and an end cover 2122. The shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c. The side wall 2121b is arranged around the bottom wall 2121c. One end of the side wall 2121b is connected to the bottom wall 2121c, and the other end of the side wall 2121b forms an opening 2121a opposite to the bottom wall 2121c. The side wall 2121b and the bottom wall 2121c jointly define a accommodating cavity for accommodating the electrode assembly 22. The end cover 2122 closes the opening 2121a, and the end cover 2122 is electrically connected to the side wall 2121b. The bottom wall 2121c is the first electrode lead-out portion 211. Along the first direction X, the first current collecting member 23 is disposed between the end cap 2122 and the electrode assembly 22. A first electrode tab 221 is formed at the end of the electrode assembly 22 facing the first current collecting member 23. The first current collecting member 23 connects the first electrode tab 221 and the end cap 2122. A protrusion 2122a is provided on the side of the end cap 2122 facing the first current collecting member 23. The protrusion 2122a is welded to the first current collecting member 23. A pressure relief mechanism 25 is disposed on the end cap 2122 and is configured to relieve internal pressure in the battery cell 20.

[0268] The first current collecting member 23 is provided with a through hole 231, which extends through the first current collecting member 23 along a first direction X. The wall surface of the through hole 231, along its orthographic projection in the first direction X, forms a plurality of first angles 232. The angle of the first angle 232 facing the through hole 231 is β, satisfying the condition 30°≤β≤90°. The plurality of first angles 232 are arranged sequentially along the circumference of the through hole 231, and the angles of the plurality of first angles 232 are identical. Along the circumference of the through hole 231, the wall surface of the through hole 231 includes a plurality of first wall surfaces 2311. A first angle 232 is formed between each adjacent pair of first wall surfaces 2311, and each pair of adjacent first wall surfaces 2311 is connected by a chamfered surface 2312. The first current collecting member 23 is a disc-shaped structure, with the central axis of the first current collecting member 23 coinciding with the central axis of the through hole 231. In FIG. 7 , the orthographic projection of the through hole 231 along the first direction X is an equilateral triangle. In FIG. 8 , the orthographic projection of the through hole 231 along the first direction X is a square.

[0269] According to some embodiments of the present application, referring to FIG. 3 to FIG. 5 and FIG. 9 to FIG. 10 , the present application provides a battery cell 20 , which includes a housing assembly 21 , an electrode assembly 22 , a first current collecting member 23 and a pressure relief mechanism 25 . The shell assembly 21 includes a shell 212 and a first electrode lead-out portion 211 for inputting or outputting electrical energy. The shell 212 is cylindrical, and the electrode assembly 22 is accommodated in the shell 212. The shell 212 includes a shell 2121 and an end cover 2122. The shell 2121 includes an integrally formed side wall 2121b and a bottom wall 2121c. The side wall 2121b is arranged around the bottom wall 2121c. One end of the side wall 2121b is connected to the bottom wall 2121c, and the other end of the side wall 2121b forms an opening 2121a opposite to the bottom wall 2121c. The side wall 2121b and the bottom wall 2121c jointly define a accommodating cavity for accommodating the electrode assembly 22. The end cover 2122 closes the opening 2121a, and the end cover 2122 is electrically connected to the side wall 2121b. The bottom wall 2121c is the first electrode lead-out portion 211. Along the first direction X, the first current collecting member 23 is disposed between the end cap 2122 and the electrode assembly 22. A first electrode tab 221 is formed at the end of the electrode assembly 22 facing the first current collecting member 23. The first current collecting member 23 connects the first electrode tab 221 and the end cap 2122. A protrusion 2122a is provided on the side of the end cap 2122 facing the first current collecting member 23. The protrusion 2122a is welded to the first current collecting member 23. A pressure relief mechanism 25 is disposed on the end cap 2122 and is configured to relieve internal pressure in the battery cell 20.

[0270] The first current collecting member 23 is provided with a through hole 231 that extends through the first current collecting member 23 along a first direction X. The wall surface of the through hole 231 forms multiple angles along its orthographic projection along the first direction X. Along the circumference of the through hole 231, the wall surface of the through hole 231 includes multiple first wall surfaces 2311. Each adjacent pair of first wall surfaces 2311 forms an angle, including multiple first angles 232 and multiple second angles 233. The angle of the first angle 232 facing the through hole 231 is β, satisfying the condition 30°≤β≤90°. The angle of the second angle 233 facing the through hole 231 is greater than 180°. Along the circumference of the through hole 231, the first angles 232 and the second angles 233 are alternately arranged. The angles of the multiple first angles 232 and the multiple second angles 233 are all the same. Each adjacent pair of first wall surfaces 2311 is connected by a chamfered surface 2312. The first current collecting member 23 is a disc-shaped structure, and the central axis of the first current collecting member 23 coincides with the central axis of the through hole 231 .

[0271] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0272] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: include: A housing assembly including a first electrode lead-out portion for inputting or outputting electrical energy; an electrode assembly, housed in the housing assembly; as well as a first current collecting member, contained in the housing assembly, located at one end of the electrode assembly along a first direction, and electrically connecting the first electrode lead-out portion and the electrode assembly; The first current collecting component is provided with a through hole, which penetrates the first current collecting component along the first direction, and the orthographic projection of the hole wall of the through hole along the first direction forms a first angle, and the orthographic projection of the through hole along the first direction is located within the first angle.

2. The battery cell according to claim 1, characterized in that: The angle of the first folded corner facing the through hole is β, which satisfies 0°<β≤90°.

3. The battery cell according to claim 2, characterized in that: 30°≤β≤90°。 4. The battery cell according to any one of claims 1 to 3, characterized in that: A plurality of first folded corners are formed on the hole wall surface of the through hole, and the plurality of first folded corners are arranged in sequence along the circumference of the through hole.

5. The battery cell according to claim 4, characterized in that: Along the circumference of the through hole, the hole wall surface of the through hole includes a plurality of first wall surfaces, and the first angle is formed between every two adjacent first wall surfaces.

6. The battery cell according to claim 5, characterized in that: The angles of the first fold angles are all the same.

7. The battery cell according to claim 6, characterized in that: The first current collecting component is a disc-shaped structure, and the central axis of the first current collecting component coincides with the central axis of the through hole.

8. The battery cell according to claim 5 or 6, characterized in that: Along the circumference of the through hole, every two adjacent first wall surfaces are connected via a chamfered surface.

9. The battery cell according to any one of claims 4 to 8, characterized in that: The orthographic projection of the through hole along the first direction is a polygon.

10. The battery cell according to claim 9, characterized in that: The orthographic projection of the through hole along the first direction is a regular polygon.

11. The battery cell according to claim 9 or 10, characterized in that: The orthographic projection of the through hole along the first direction is a triangle or a rectangle.

12. The battery cell according to any one of claims 1 to 3, characterized in that: The hole wall surface of the through hole is formed with multiple folded angles. Along the circumference of the through hole, the hole wall surface of the through hole includes multiple first wall surfaces, and the folded angle is formed between each adjacent two first wall surfaces. The multiple folded angles include the first folded angle and the second folded angle, and the angle of the second folded angle facing the side of the through hole is greater than 180°.

13. The battery cell according to claim 12, characterized in that: The plurality of folded corners include a plurality of first folded corners and a plurality of second folded corners, and along the circumference of the through hole, the first folded corners and the second folded corners are arranged alternately.

14. The battery cell according to claim 13, characterized in that: The angles of the first folded corners are all the same, and the angles of the second folded corners are all the same.

15. The battery cell according to claim 14, characterized in that: The first current collecting component is a disc-shaped structure, and the central axis of the first current collecting component coincides with the central axis of the through hole.

16. The battery cell according to any one of claims 12 to 14, characterized in that: Along the circumference of the through hole, every two adjacent first wall surfaces are connected via a chamfered surface.

17. The battery cell according to any one of claims 1 to 16, characterized in that: The electrode assembly has a central channel extending along the first direction, and at least a portion of an orthographic projection of the central channel along the first direction is located within the through hole.

18. The battery cell according to any one of claims 1 to 17, characterized in that: The battery cell is cylindrical, and the axis direction of the battery cell is the same as the first direction.

19. The battery cell according to any one of claims 1 to 18, characterized in that: The housing assembly includes a housing, the electrode assembly is accommodated in the housing, and at least a portion of the housing forms the first electrode lead-out portion.

20. The battery cell according to claim 19, characterized in that: The housing comprises: A shell, comprising an integrally formed side wall and a bottom wall, wherein the side wall is disposed around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall forms an opening opposite to the bottom wall, and the side wall and the bottom wall jointly define a housing cavity for housing the electrode assembly; an end cap for closing the opening; Wherein, the bottom wall is the first electrode lead-out portion.

21. The battery cell according to claim 20, characterized in that: Along the first direction, the first current collecting member is disposed between the end cover and the electrode assembly; wherein the first current collecting member is connected to the end cover, and the end cover is electrically connected to the side wall, so as to electrically connect the first current collecting member and the bottom wall; or The first current collecting member is connected to the side wall to electrically connect the first current collecting member and the bottom wall.

22. The battery cell according to claim 20, characterized in that: Along the first direction, the first current collecting member is disposed between the bottom wall and the electrode assembly, and the first current collecting member is connected to the bottom wall.

23. The battery cell according to claim 19, characterized in that: The housing comprises: A housing having an opening formed therein, wherein the electrode assembly is accommodated in the housing; an end cap for closing the opening; Wherein, the end cover is the first electrode lead-out portion.

24. The battery cell according to claim 23, characterized in that: Along the first direction, the first current collecting member is disposed between the end cover and the electrode assembly, and the first current collecting member is connected to the end cover.

25. The battery cell according to any one of claims 1 to 18, characterized in that: The housing assembly further comprises a housing, and the electrode assembly is accommodated in the housing; The first electrode lead-out portion is insulated and mounted on the housing, and along the first direction, at least a portion of the first current collecting member is disposed between the first electrode lead-out portion and the electrode assembly, and the first current collecting member is connected to the first electrode lead-out portion.

26. The battery cell according to claim 25, characterized in that: The housing comprises: A shell, comprising an integrally formed side wall and a bottom wall, wherein the side wall is disposed around the bottom wall, one end of the side wall is connected to the bottom wall, and the other end of the side wall forms an opening opposite to the bottom wall, and the side wall and the bottom wall jointly define a housing cavity for housing the electrode assembly; an end cap for closing the opening; Wherein, the first electrode lead-out portion is insulated and mounted on the end cover; or The first electrode lead-out portion is insulated and mounted on the bottom wall.

27. The battery cell according to any one of claims 19 to 26, characterized in that: The battery cell further comprises: a pressure relief mechanism, disposed on the housing, the pressure relief mechanism being configured to release internal pressure of the battery cell; Wherein, along the first direction, the pressure relief mechanism and the through hole are arranged opposite to each other.

28. A battery, characterized in that: Comprising a battery cell as claimed in any one of claims 1 to 27.

29. An electrical device, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 27, wherein the battery cell is used to provide electrical energy.

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