Battery cell, battery apparatus, and electric device

Abstract

A battery cell, a battery apparatus, and an electric device, relating to the technical field of batteries. The battery cell comprises: a first end cover assembly comprising a first electrode terminal; an electrode assembly comprising a main body portion and a tab extending from the main body portion; and an isolation member at least partially arranged between the first electrode terminal and the main body portion, wherein the first end cover assembly is provided with a first snap-fit structure; the isolation member is provided with a second snap-fit structure; one of the first snap-fit structure and the second snap-fit structure is provided with a snap portion, and the other of the first snap-fit structure and the second snap-fit structure is provided with a slot portion; the snap portion is snap-fitted to the slot portion, the snap portion is provided with a first snap-fit surface, the slot portion is provided with a second snap-fit surface, the dimensions of the first snap-fit surface and the second snap-fit surface in a first direction are smaller than those in a second direction, the first direction is a length direction of the isolation member, and the second direction is a width direction of the isolation member. The technical solution of the present application facilitates improving the reliability of battery cells.

Description

Battery cell, battery device and electric equipment Cross-reference to related applications

[0001] This application claims priority to Chinese Patent Application No. 202422355656.7, filed on September 26, 2024, entitled “Battery cell, battery device and electric equipment”, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the field of batteries, and more particularly, to a battery cell, a battery device and an electric equipment. BACKGROUND

[0003] New energy industry is attracting more and more attention. In the new energy industry, battery technology is an important factor for its development.

[0004] The development of battery technology needs to consider many design factors, such as energy density, cycle life, reliability, etc., among which the structure of the battery cell is crucial to the reliability of the battery. Therefore, how to provide a battery cell to improve the reliability of the battery is an urgent technical problem to be solved. SUMMARY

[0005] The embodiments of the present application provide a battery cell, a battery device and an electric equipment, which can improve the reliability of the battery cell.

[0006] In a first aspect, a battery cell is provided, comprising: a first end cover assembly comprising a first electrode terminal; an electrode assembly accommodated in the housing, the electrode assembly comprising a main body portion and a tab extending from the main body portion; an isolation member at least partially disposed between the first electrode terminal and the main body portion; wherein the first end cover assembly is provided with a first clamping structure, the isolation member is provided with a second clamping structure, one of the first clamping structure and the second clamping structure has a clamping portion, and the other has a clamping groove portion, the clamping portion and the clamping groove portion are clamped, the clamping portion has a first clamping surface, the clamping groove portion has a second clamping surface, the first clamping surface and the second clamping surface have a dimension along a first direction smaller than a dimension along a second direction, the first direction is a length direction of the isolation member, and the second direction is a width direction of the isolation member.

[0007] In the embodiment of the present application, the isolation member is at least partially arranged between the first electrode terminal and the main body portion, so that at least part of the tab can be isolated from the main body portion of the electrode assembly, thereby reducing the risk of the tab being inserted into the main body portion and the risk of short circuit of the battery cell when the battery cell is impacted or the like. The first clamping structure of the first end cover assembly and the second clamping structure of the isolation member are clamped, one of the first clamping structure and the second clamping structure has a buckle portion, and the other has a clamping groove portion, the buckle portion and the clamping groove portion are clamped, thereby realizing the fixation between the first end cover assembly and the isolation member. The buckle portion has a first clamping surface, and the clamping groove portion has a second clamping surface, the size of the first clamping surface and the second clamping surface along the first direction is smaller than the size along the second direction, so that the area of the overlapping region between the buckle portion and the clamping groove portion can be increased, the risk of the buckle portion being separated from the clamping groove portion can be reduced, and the connection strength between the buckle portion and the clamping groove portion can be increased, thereby the risk of the isolation member moving in the battery cell can be reduced, and the risk of the tab being pulled and torn can be reduced. Therefore, the technical scheme of the embodiment of the present application is beneficial to improve the reliability of the battery cell.

[0008] In some embodiments, the first clamping structure is a protruding structure protruding towards the electrode assembly along a third direction, the protruding structure includes the buckle portion, and the second clamping structure is an opening structure corresponding to the protruding structure, the opening structure includes the clamping groove portion. In this way, the buckle portion of the protruding structure is clamped into the clamping groove portion of the opening structure, thereby realizing the connection between the first end cover assembly and the isolation member; in addition, the first clamping structure is a protruding structure, and the second clamping structure is an opening structure, which is beneficial to the processing of the first end cover assembly and the isolation member.

[0009] In some embodiments, the first clamping surface has a first profile, the first profile includes a first straight line segment extending along the second direction; the second clamping surface has a second profile, the second profile includes a third straight line segment extending along the second direction; and the first profile and the second profile are perpendicular to the third direction.

[0010] In the above technical scheme, the first straight line segment and the third straight line segment extend along the second direction, which is beneficial to the processing of the buckle portion and the clamping groove portion, and is also beneficial to increasing the area of the overlapping region between the buckle portion and the clamping groove portion and improving the connection strength between the first end cover assembly and the isolation member.

[0011] In some embodiments, the length L1 of the first straight line segment satisfies: 0.5mm≤L1≤5mm, and / or the length L2 of the third straight line segment satisfies: 0.5mm≤L2≤5mm. In this way, L1 and L2 have a suitable size, the overlapping area between the first clamping surface of the buckle portion and the second clamping surface of the clamping groove portion has a larger area, the connection strength between the first end cover assembly and the isolation member is larger, which is beneficial to reduce the risk of movement of the isolation member in the battery monomer and tearing of the tab, and the buckle portion and the clamping groove portion have higher structural strength, and the battery monomer has higher reliability.

[0012] In some embodiments, 2mm≤L1≤4mm, and / or 2mm≤L2≤4mm. In this way, the buckle portion and the clamping groove portion have higher connection strength, and the buckle portion and the clamping groove portion have higher structural strength, and the battery monomer has higher reliability.

[0013] In some embodiments, the first profile includes a first arc segment and a second arc segment, and the first arc segment and the second arc segment are respectively connected to two ends of the first straight line segment. In this way, it is convenient for the buckle portion to enter the clamping groove portion.

[0014] In some embodiments, the radius R1 of the first arc segment and the second arc segment satisfies: 0.3mm≤R1≤2.5mm. In this way, the first arc segment and the second arc segment have a suitable size, which is convenient for processing of the buckle portion and smooth entry of the buckle portion into the clamping groove portion.

[0015] In some embodiments, 1.0mm≤R1≤2.1mm. In this way, the first arc segment and the second arc segment have a suitable size, which is convenient for processing of the buckle portion and smooth entry of the buckle portion into the clamping groove portion.

[0016] In some embodiments, the first profile includes a second straight line segment, the second straight line segment is parallel to the first direction, and two ends of the first arc segment are respectively connected to the first straight line segment and the second straight line segment. In this way, the area of the overlapping area between the clamping groove portion of the opening structure and the buckle portion of the protruding structure is larger, and the protruding structure is not easy to come out of the opening structure.

[0017] In some embodiments, the second profile includes a third arc segment and a fourth arc segment, and the third arc segment and the fourth arc segment are respectively connected to two ends of the third straight line segment. In this way, it is convenient for the buckle portion to enter the clamping groove portion.

[0018] In some embodiments, the radius R2 of the third arc segment and the fourth arc segment satisfies: 0.5mm≤R2≤2.7mm. In this way, the third arc segment and the fourth arc segment have a suitable size, which is convenient for processing of the clamping groove portion and smooth entry of the buckle portion into the clamping groove portion.

[0019] In some embodiments, 1.2mm≤R2≤2.3mm. In this way, the third arc segment and the fourth arc segment have a suitable size, facilitating the processing of the clamping groove portion and the smooth entry of the clamping portion into the clamping groove portion.

[0020] In some embodiments, along the first direction, the size L3 of the overlapping area of the clamping portion and the clamping groove portion satisfies: 0.15mm≤L3≤0.5mm, the first direction being the length direction of the isolation member. In this way, the overlapping area between the clamping portion and the clamping groove portion has a larger area, the connection strength between the first end cover assembly and the isolation member is larger, the risk of the isolation member moving in the battery monomer and the risk of the tab tearing are lower, and the battery monomer has higher reliability.

[0021] In some embodiments, 0.2mm≤L3≤0.4mm. In this way, the overlapping area between the clamping portion and the clamping groove portion has a larger area, the connection strength between the first end cover assembly and the isolation member is larger, the risk of the isolation member moving in the battery monomer and the risk of the tab tearing are lower, and the battery monomer has higher reliability.

[0022] In some embodiments, the protruding structure includes a clamping portion, a connecting portion, and a transition portion, the two ends of the connecting portion along the third direction are respectively connected with the transition portion and the clamping portion; the opening structure includes the clamping groove portion, a limiting portion, and a guide portion, the two ends of the limiting portion along the third direction are respectively connected with the guide portion and the clamping groove portion.

[0023] In the above technical solution, the guide portion can guide the protruding structure to enter the opening structure, and the limiting portion can limit the movement of the clamping portion along the third direction after the clamping portion of the protruding structure enters the clamping groove portion, thereby reducing the risk of the clamping portion separating from the clamping groove portion.

[0024] In some embodiments, along the first direction, the size D1 of the limiting portion, the size D2 of the connecting portion, and the size D3 of the clamping portion satisfy: D2<D1<D3.

[0025] In the above technical solution, the movement of the clamping portion along the third direction can be limited after the clamping portion of the protruding structure enters the clamping groove portion, thereby reducing the risk of the clamping portion separating from the clamping groove portion, and the connecting portion can pass through the limiting portion and at least partially enter the clamping groove portion.

[0026] In some embodiments, 0.05mm≤D1-D2≤1mm. In this way, the limiting portion of the opening structure and the connecting portion of the protruding structure have a suitable size, which can make the connecting portion pass through the limiting portion and at least partially enter the clamping groove portion, and can reduce the risk of the clamping portion separating from the clamping groove portion.

[0027] In some embodiments, 0.4mm≤D1-D2≤0.6mm. In this way, the limiting portion of the opening structure and the connecting portion of the protruding structure have appropriate sizes, which can enable the connecting portion to enter the clamping groove portion through the limiting portion, and can reduce the risk of the clamping portion coming out of the clamping groove portion.

[0028] In some embodiments, the protruding structure comprises a deformation groove, the deformation groove penetrating through the clamping portion and at least part of the connecting portion along the third direction, and a width direction of the deformation groove being perpendicular to the second direction. In this way, the clamping portion and the connecting portion can be deformed along the first direction, which facilitates the clamping portion to be clamped into the clamping groove portion.

[0029] In some embodiments, along the first direction, a size D4 of the deformation groove satisfies: 0.3mm≤D4≤1.5mm. In this way, the deformation groove has appropriate sizes in the first direction, which facilitates the clamping portion to enter the clamping groove portion during assembly of the first end cover assembly and the isolation member, and the protruding structure has appropriate strength, which is conducive to assembly of the battery monomer and improvement of reliability of the battery monomer.

[0030] In some embodiments, 0.7mm≤D4≤1.1mm. In this way, the deformation groove has appropriate sizes in the first direction, which facilitates the clamping portion to be smoothly clamped into the clamping groove portion while the strength of the protruding structure is taken into account, which is conducive to assembly of the battery monomer and improvement of reliability of the battery monomer.

[0031] In some embodiments, the first end cover assembly is provided with two first clamping structures, and the two first clamping structures are respectively arranged at end regions of the first end cover assembly along the first direction; and the isolation member is provided with two second clamping structures, and the two second clamping structures are respectively arranged at end regions of the isolation member along the first direction.

[0032] In the above technical solution, the two first clamping structures and the two second clamping structures are arranged, which is conducive to increasing the connection strength between the first end cover assembly and the isolation member. In addition, the second clamping structure is arranged at the end region of the isolation member along the first direction, which facilitates the channel for the tab to pass through to be arranged at the middle region of the isolation member, so as to facilitate the tab to be electrically connected with the first electrode terminal.

[0033] In some embodiments, the isolation member is provided with a channel, the channel is arranged at a middle region of the isolation member along the first direction, and the tab passes through the channel and is electrically connected with the first electrode terminal.

[0034] In the above technical solution, the channel is arranged at the middle region of the isolation member along the first direction, and the channel corresponds to the tab, which facilitates the tab to pass through the channel and be electrically connected with the first electrode terminal.

[0035] In some embodiments, the first end cover assembly includes an end cover and an insulating piece, the end cover is configured to cover the first opening, and the insulating piece is provided with the first clamping structure.

[0036] In the technical solution described above, the end cover covers the first opening of the shell, and the first electrode terminal on the end cover is electrically connected with the tab, and the first clamping structure of the insulating piece is clamped with the second clamping structure of the isolation member. By providing the first end cover assembly, the connection of the first end cover assembly, the isolation member and the electrode assembly is facilitated.

[0037] In a second aspect, a battery device is provided, which includes the battery cell of the first aspect or any one of the embodiments of the first aspect.

[0038] In a third aspect, a use electric device is provided, which includes the battery device of the second aspect.

[0039] In the embodiments of the present application, the isolation member is at least partially arranged between the first electrode terminal and the main body part, so that at least part of the tab can be isolated from the main body part of the electrode assembly, thereby reducing the risk of the tab being inserted into the main body part and the risk of short circuit of the battery cell when the battery cell is impacted or the like. The first clamping structure of the first end cover assembly is clamped with the second clamping structure of the isolation member, one of the first clamping structure and the second clamping structure has a clamping portion, and the other has a clamping groove portion, the clamping portion is clamped with the clamping groove portion, thereby realizing the fixation between the first end cover assembly and the isolation member. The clamping portion has a first clamping surface, and the clamping groove portion has a second clamping surface, the size of the first clamping surface and the second clamping surface along the first direction is smaller than the size along the second direction, so that the area of the overlapping region between the clamping portion and the clamping groove portion can be increased, the risk of the clamping portion being separated from the clamping groove portion can be reduced, and the connection strength between the clamping portion and the clamping groove portion can be increased, thereby reducing the risk of the isolation member moving in the battery cell, and further reducing the risk of the tab being pulled and torn. Therefore, the technical solution of the embodiments of the present application is beneficial to improve the reliability of the battery cell. BRIEF DESCRIPTION OF DRAWINGS

[0040] FIG. 1 is a schematic view of a vehicle according to an embodiment of the present application;

[0041] FIG. 2 is a structural schematic view of a battery device according to an embodiment of the present application;

[0042] FIG. 3 is a structural schematic view of a battery cell according to an embodiment of the present application;

[0043] FIG. 4 is an exploded structural schematic view of a battery cell according to an embodiment of the present application;

[0044] FIG. 5 is a top view of a battery cell according to an embodiment of the present application;

[0045] Fig. 6 is a sectional view of the battery cell in Fig. 5 along the direction of A-A;

[0046] Fig. 7 is an enlarged schematic view of the region C in Fig. 6;

[0047] Fig. 8 is a sectional view of the battery cell in Fig. 7 along the direction of B-B;

[0048] Fig. 9 is an enlarged schematic view of the region D in Fig. 8;

[0049] Fig. 10 is a schematic view of a first profile according to an embodiment of the present application;

[0050] Fig. 11 is a schematic view of a second profile according to an embodiment of the present application;

[0051] Fig. 12 is a schematic view of a structure of a first end cover assembly according to an embodiment of the present application;

[0052] Fig. 13 is an enlarged schematic view of the region E in Fig. 12;

[0053] Fig. 14 is a schematic view of a structure of a separation member according to an embodiment of the present application;

[0054] Fig. 15 is a top view of the separation member according to an embodiment of the present application;

[0055] Fig. 16 is a schematic view of a protruding structure according to an embodiment of the present application;

[0056] Fig. 17 is a schematic view of an opening structure according to an embodiment of the present application.

[0057] In the drawings, the drawings are not drawn according to the actual proportions.

[0058] Reference signs: 1: vehicle; 10: battery device; 30: controller; 40: motor; 20: battery cell; 11: case; 111: first case portion; 112: second case portion; 21: housing; 22: electrode assembly; 23: separation member; 24: first end cap assembly; 25: second end cap assembly; 230: side wall; 2301: first side wall; 2302: second side wall; 231: separation plate; 232: reinforcing structure; 237: through hole; 2330: passage; 26: insulating film; 27: side support plate; 211: first opening; 212: second opening; 240: first electrode terminal; 251: second electrode terminal; 221: main body portion; 222: tab; 241: end cap; 242: insulating member; 5: first clamping structure; 6: second clamping structure; 50: protruding structure; 501: clamping portion; 502: connecting portion; 503: transition portion; 504: deformation groove; 505: first fixing portion; 60: opening structure; 601: clamping groove portion; 602: limiting portion; 603: guide portion; 604: second fixing portion; 80: first profile; 81: first straight line segment; 82: first arc line segment; 83: second arc line segment; 84: second straight line segment; 90: first profile; 91: third straight line segment; 92: third arc line segment; 93: fourth arc line segment. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be described below with reference to the drawings.

[0060] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the specification herein is for describing the specific embodiments only and is not intended to be limiting of the application; the use of the terms "including," "comprising," "having" and "with" in the specification and claims herein are used to mean "including but not limited to"; the use of the terms "first," "second," and the like in the specification and claims herein is intended to modify, respectively, a limitation described in the specification and claims herein but does not denote description herein of a specific sequential order, unless otherwise noted.

[0062] Reference to an "embodiment" in this application means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. As used in this application, the term "exemplary" is intended to mean serving as an instance or illustration. Any implementation having "exemplary" characteristics is preferred only as compared to one or more other possible implementations having different or no exemplary characteristics.

[0063] In the description of the application, it is necessary to explain that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "attaching" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0064] The term "and / or" in this application is only to describe the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this application generally represents that the front and rear associated objects have an "or" relationship.

[0065] In the embodiments of the application, the same reference signs represent the same parts, and for the sake of brevity, the detailed description of the same parts is omitted in different embodiments. It should be understood that the thickness, length and width of various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length and width of the integrated device, are only exemplary and should not constitute any limitation on the application.

[0066] "Multiple" appearing in this application means more than two (including two), and similarly, "multiple groups" means more than two groups (including two groups), and "multiple pieces" means more than two pieces (including two pieces).

[0067] If not specifically stated, all embodiments and optional embodiments of the application can be combined with each other to form new technical solutions.

[0068] If not specifically stated, all technical features and optional technical features of the application can be combined with each other to form new technical solutions.

[0069] If not otherwise specified, all steps of the present application can be performed in sequence or randomly, preferably in sequence. For example, the method comprises steps (a) and (b) means that the method can comprise steps (a) and (b) in sequence, or steps (b) and (a) in sequence. For example, the method can further comprise step (c) means that step (c) can be added to the method in any sequence, for example, the method can comprise steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0070] In the embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0071] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., which are not limited in the embodiments of the present application.

[0072] The battery cell generally comprises an electrode assembly. The electrode assembly comprises a positive electrode, a negative electrode and a separator, and the separator is arranged between the negative electrode and the positive electrode. During the charging and discharging process of the battery cell, active ions (such as lithium ions) are inserted and extracted between the positive electrode and the negative electrode. The separator arranged between the positive electrode and the negative electrode can prevent the positive and negative electrodes from short-circuiting, and at the same time allow the active ions to pass through.

[0073] In some embodiments, the positive electrode can be a positive electrode tab, which can comprise a positive electrode current collector and a positive electrode active material arranged on at least one surface of the positive electrode current collector.

[0074] As an example, the positive electrode current collector has two opposite surfaces in the thickness direction of itself, and the positive electrode active material is arranged on any one or both of the two opposite surfaces of the positive electrode current collector.

[0075] As an example, the positive electrode current collector can adopt a metal foil, a conductive polymer material, a carbon material or a composite current collector. For example, as a metal foil, pure metal, alloy, surface-treated metal can be adopted, including but not limited to stainless steel, copper, aluminum, nickel, nickel, titanium or silver, etc. The composite current collector can comprise a polymer material base layer and a metal layer. The composite current collector can 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 base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0076] As an example, the positive electrode active material can include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery positive electrode active material can also be used. These positive electrode active materials can be used alone only one or two or more can be used in combination. Among them, examples of the lithium-containing phosphate can include, but are not limited to, at least one of lithium iron phosphate (such as LiFeP04 (which can also be referred to simply as LFP)), a composite of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnP04), a composite of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxide can include, but are not limited to, at least one of lithium cobalt oxide (such as LiCo02), lithium nickel oxide (such as LiNi02), lithium manganese oxide (such as LiMn02, LiMn204), 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 (which can also be referred to simply as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be referred to simply as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be referred to simply as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2 (which can also be referred to simply as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be referred to simply as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi 0.8 Co 0.15 Al 0.05 O2), and modified compounds thereof. The modified compound refers to a substance obtained by a modification means such as doping or coating on the basis of the above-mentioned substance.

[0077] In some embodiments, the positive electrode can employ a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When the foamed metal is used as the positive electrode, the foamed metal surface can not be provided with the positive electrode active material, or of course can be provided with the positive electrode active material. As an example, the positive electrode active material is filled or / and deposited in the foamed metal.

[0078] In some embodiments, the negative electrode can be a negative electrode tab, and the negative electrode tab can include a negative electrode current collector.

[0079] As an example, the negative current collector can employ a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, a pure metal, an alloy, a surface-treated metal, including but not limited to stainless steel, copper, aluminum, nickel, nickel, titanium, or silver, etc. can be employed. 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 base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0080] As an example, the negative electrode tab can include a negative current collector and a negative active material disposed on at least one surface of the negative current collector.

[0081] As an example, the negative current collector has two surfaces opposite in the thickness direction thereof, and the negative active material is disposed on either one or both of the two opposite surfaces of the negative current collector.

[0082] As an example, the negative active material can employ a negative active material for a battery cell known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a negative active material for a battery cell can also be used. These negative active materials can be used alone only one or in combination of two or more.

[0083] In some embodiments, the negative electrode can employ a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, or foamed carbon, etc. When the foamed metal is used as a negative electrode tab, the surface of the foamed metal can not be provided with a negative active material, and of course, can be provided with a negative active material.

[0084] As an example, the negative active material can be filled or / and deposited in the negative current collector.

[0085] In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0086] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0087] In some embodiments, the separator is a separator film. The type of separator film is not particularly limited in the present application, and any known porous separator film having good chemical stability and mechanical stability can be used.

[0088] As an example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator film can be a single layer film or a multi-layer composite film, and is not particularly limited. When the separator film is a multi-layer composite film, the materials of the respective layers can be the same or different, and are not particularly limited. The separator can be a separate component located between the positive and negative electrodes, or can be attached to the surface of the positive and negative electrodes. An inorganic particle coating, an organic particle coating, or an organic / inorganic composite coating can be applied to the surface of the separator film.

[0089] In some embodiments, the separator is a solid-state electrolyte. The solid-state electrolyte is disposed between the positive and negative electrodes, and functions to transport ions and separate the positive and negative electrodes.

[0090] In some embodiments, the battery cell further includes an electrolyte that functions to conduct ions between the positive and negative electrodes. The type of electrolyte is not particularly limited in the present application, and can be selected as needed. The electrolyte can be in a liquid state, a gel state, or a solid state.

[0091] The liquid electrolyte includes an electrolyte salt and a solvent.

[0092] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonylimide, lithium bis-trifluoromethanesulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro oxalate borate, lithium di-oxalate borate, lithium difluoro di-oxalate phosphate, and lithium tetrafluoro oxalate phosphate.

[0093] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, butanedisulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether-based solvent. The ether-based solvent can 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, methyl tetrahydrofuran, diphenyl ether, and crown ether.

[0094] In some embodiments, the electrolyte can also optionally include an additive. For example, the additive can include a negative electrode film-forming additive, a positive electrode film-forming additive, and an additive capable of improving certain performance of the battery cell, such as an additive capable of improving overcharge / fast charge performance of the battery cell, an additive capable of improving high-temperature performance of the battery cell, an additive capable of improving low-temperature performance of the battery cell, and the like.

[0095] In some embodiments, the gel-state electrolyte includes a polymer as a skeleton network and can be used in combination with an ionic liquid-lithium salt.

[0096] In some embodiments, the solid-state electrolyte includes a polymer solid-state electrolyte, an inorganic solid-state electrolyte, and a composite solid-state electrolyte.

[0097] As an example, the polymer of the polymer solid-state electrolyte can include a polyether (polyethylene oxide), a polysiloxane, a polycarbonate, a polyacrylonitrile, a polyvinylidene fluoride, a polymethyl methacrylate, a single-ion polymer, a polyionic liquid, cellulose, and the like.

[0098] As an example, the inorganic solid-state electrolyte can be one or more of an oxide solid-state electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid-state electrolyte (crystalline lithium superionic conductor (lithium-ephosphorus-sulfur, sulfur-silver-ephemeral mineral), amorphous sulfide), and a halide solid-state electrolyte, a nitride solid-state electrolyte, and a hydride solid-state electrolyte.

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

[0100] The technical solutions described in the embodiments of the present application are applicable to various power consumption devices using battery cells, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships, and spacecraft, such as aircraft, rockets, space shuttles, and spacecraft.

[0101] At present, from the development of market situation, the application of power battery is more and more widely. Power battery is not only applied to energy storage power supply system of hydropower, thermal power, wind power and solar power station, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric vehicles, electric vehicles, military equipment and aerospace and other fields. With the continuous expansion of the application field of power battery, the demand of its market is also increasing.

[0102] The development of battery technology needs to consider various design factors, such as energy density, cycle life, discharge capacity, charge-discharge rate, reliability, etc., among which the structure of the battery cell is crucial to the performance of the battery cell. The battery cell includes an electrode assembly, an end cover assembly, a separation member, and a housing, wherein the housing is used to accommodate the electrode assembly, the end cover assembly is used to cover the housing, and the separation member is at least partially arranged between the tab and the electrode assembly to facilitate the connection of the tab and the electrode terminal of the end cover assembly. During the use or transportation of the battery cell, when the battery cell is subjected to impact, extrusion, vibration, etc., the separation member is prone to move, thereby affecting the support effect on the tab and being not conducive to the improvement of the reliability of the battery cell.

[0103] In some processing modes, a first clamping structure is arranged on the end cover assembly, a second clamping structure is arranged on the separation member, and the first clamping structure and the second clamping structure are clamped to achieve fixed connection between the end cover assembly and the separation member. However, the area of the overlapping region between the first clamping structure and the second clamping structure is small, the first clamping structure is prone to be separated from the second clamping structure, the separation member is at high risk of moving in the battery cell, and the tab is at risk of tearing, which is not conducive to the improvement of the reliability of the battery cell.

[0104] Therefore, the present application provides a battery cell, which includes a first end cover assembly and a separation member, the first end cover assembly is provided with a first clamping structure, the separation member is provided with a second clamping structure, one of the first clamping structure and the second clamping structure has a clasp part, and the other has a clamping groove part, the clasp part and the clamping groove part are clamped, the clasp part has a first clamping surface, the clamping groove part has a second clamping surface, the size of the first clamping surface and the second clamping surface along a first direction is smaller than the size along a second direction, the first direction is the length direction of the separation member, and the second direction is the width direction of the separation member. In this way, compared with the case that the first clamping surface and the second clamping surface are the same in the first direction and the second direction, for example, the profiles of the first clamping surface and the second clamping surface are circular, the area of the overlapping region of the second clamping surface and the second clamping surface is larger, the risk of the clasp part being separated from the clamping groove part is lower, the connection strength between the first end cover assembly and the separation member is larger, the separation member is not prone to move and the risk of the tab tearing is lower, and the battery cell has higher reliability.

[0105] The technical solutions described in the embodiments of the present application are applicable to various electric equipment using battery devices.

[0106] The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, and an electric tool, etc. The vehicle can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile, or a range extended automobile, etc. The spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft, etc. The electric toy includes a fixed or mobile electric toy, such as a game machine, an electric automobile toy, an electric ship toy, and an electric airplane toy, etc. The electric tool includes a metal cutting electric tool, a grinding electric tool, an assembling electric tool, and a railway electric tool, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact electric drill, a concrete vibrator, and an electric planer, etc. The electric device is not specially limited in the embodiments of the present application.

[0107] The following embodiments take the vehicle as an example for convenience of description.

[0108] FIG. 1 is a structural schematic diagram of a vehicle according to an embodiment of the present application. For example, as shown in FIG. 1, the vehicle 1 can be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile can be a pure electric automobile, a hybrid electric automobile, or a range extended automobile, etc. The vehicle 1 can be provided with a motor 40, a controller 30, and a battery device 10 inside, and the controller 30 is used to control the battery device 10 to supply power to the motor 40. For example, the battery device 10 can be arranged at the bottom, the front, or the rear of the vehicle 1. The battery device 10 can be used to supply power to the vehicle 1, for example, the battery device 10 can be used as an operating power source of the vehicle 1, and is used for the circuit system of the vehicle 1, for example, for the power demand of the vehicle 1 during starting, navigation, and running. In another embodiment of the present application, the battery device 10 can not only be used as an operating power source of the vehicle 1, but also be used as a driving power source of the vehicle 1, to replace or partially replace the fuel or natural gas to provide driving power for the vehicle 1.

[0109] FIG. 2 is a structural schematic diagram of a battery device according to an embodiment of the present application. For example, as shown in FIG. 2, the battery device 10 according to the embodiments of the present application can include a plurality of battery monomers 20 to meet different power demands. The shape of the battery monomer 20 according to the embodiments of the present application can be set according to actual application. For example, the battery monomer 20 can be a cuboid as shown in FIG. 2, or can be a cylinder or other shape different from that shown in FIG. 2, which is not limited in the embodiments of the present application.

[0110] It should be understood that, as shown in FIG. 2, the battery device 10 of the embodiments of the present application can also include a box 11, which can be used to accommodate a plurality of battery cells 20. The box 11 of the embodiments of the present application is a hollow structure inside which the plurality of battery cells 20 are accommodated. The box 11 can include two parts, which are referred to as a first box part 111 and a second box part 112 herein, and the first box part 111 and the second box part 112 are buckled together. The shapes of the first box part 111 and the second box part 112 can be determined according to the shapes of the components accommodated inside, for example, according to the shape of the combination of the plurality of battery cells 20, and at least one of the first box part 111 and the second box part 112 has an opening. For example, as shown in FIG. 2, the first box part 111 and the second box part 112 can each be a hollow cuboid and each have a face as an opening face, the opening of the first box part 111 and the opening of the second box part 112 are oppositely arranged, and the first box part 111 and the second box part 112 are buckled to each other to form a box 11 having a closed cavity, which can be used to accommodate the plurality of battery cells 20. The plurality of battery cells 20 combined in parallel or in series or in a hybrid combination are placed in the box 11 formed after the buckling of the first box part 111 and the second box part 112.

[0111] For another example, unlike that shown in FIG. 2, only one of the first box part 111 and the second box part 112 can be a hollow cuboid having an opening, and the other can be a plate-shaped to cover the opening. Taking the second box part 112 as a hollow cuboid having an opening and the first box part 111 as a plate-shaped as an example, the first box part 111 covers the opening of the second box part 112 to form a box 11 having a closed cavity, which can be used to accommodate the plurality of battery cells 20.

[0112] FIG. 3 is a structural schematic diagram of a battery cell of an embodiment of the present application, FIG. 4 is an exploded structural schematic diagram of the battery cell of the embodiment of the present application, FIG. 5 is a top view of the battery cell of the embodiment of the present application, FIG. 6 is a sectional view of the battery cell in FIG. 5 along the direction of A-A, FIG. 7 is an enlarged schematic diagram of region C in FIG. 6, FIG. 8 is a sectional view of the battery cell in FIG. 7 along the direction of B-B, and FIG. 9 is an enlarged schematic diagram of region D in FIG. 8.

[0113] The embodiments of the present application provide a battery cell 20, for example, as shown in FIGS. 3 to 9, which includes a first end cover assembly 24, an electrode assembly 22 and a separation member 23.

[0114] The battery cell 20 can also include a shell 21 having a first opening 211, and the first end cover assembly 24 is used to cover the first opening 211.

[0115] The shell 21 can be a hollow structure with an opening on one side or a hollow structure with openings on both sides. For example, the shell 21 is provided with one opening, which is a first opening 211. For another example, the shell 21 can also be provided with an opening in addition to the first opening 211.

[0116] The shell 21 is used to accommodate the electrode assembly 22, and the shape of the shell 21 can be determined according to the shape of one or more electrode assemblies 22 combined, for example, as shown in FIG. 4, the shell 21 is a hollow cuboid. Embodiments of the present application include but are not limited to this, the shell 21 can also be a hollow cube, a cylinder or other shapes.

[0117] The material of the shell 21 can be various, such as the material of the shell 21 can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite shell) or an aluminum plastic film, etc.

[0118] The first end cover assembly 24 includes a first electrode terminal 240, which is used to electrically connect the electrode assembly 22 with the circuit outside the battery monomer 20 to realize the charging and discharging of the electrode assembly 22. As an example, at least part of the first electrode terminal 240 is exposed to the outside of the battery monomer 20 to facilitate connection with the busbar component, thereby leading out the electrical energy generated by the electrode assembly 22.

[0119] The electrode assembly 22 is accommodated in the shell 21, and the electrode assembly 22 includes a main body part 221 and a tab 222 extending from the main body part 221.

[0120] The electrode assembly 22 can be a winding structure, a laminated structure, or a hybrid structure of winding and lamination.

[0121] In some embodiments, the electrode assembly 22 is a winding structure. The positive electrode tab and the negative electrode tab are wound into a winding structure.

[0122] In some embodiments, the electrode assembly 22 is a laminated structure.

[0123] As an example, a plurality of positive electrode tabs and a plurality of negative electrode tabs can be provided respectively, and the plurality of positive electrode tabs and the plurality of negative electrode tabs are alternately and laminatedly arranged. As an example, a plurality of positive electrode tabs can be provided, and the negative electrode tab is folded to form a plurality of laminatedly arranged folded sections, and one positive electrode tab is clamped between adjacent folded sections.

[0124] As an example, the positive electrode tab and the negative electrode tab are both folded to form a plurality of laminatedly arranged folded sections.

[0125] As an example, a plurality of isolation pieces can be provided, and each isolation piece is arranged between any adjacent positive electrode tab or negative electrode tab.

[0126] As an example, the isolation member can be continuously provided between any adjacent positive electrode tab or negative electrode tab by means of folding or winding.

[0127] In some embodiments, the electrode assembly 22 can have a cylindrical shape, a flat shape, or a multi-prism shape, etc.

[0128] The tab 222 can be directly connected to the first electrode terminal 240, or indirectly connected to the first electrode terminal 240 via other conductive structures.

[0129] The tab 222 can be provided in a plurality of pieces. The plurality of tabs 222 includes positive electrode tabs and negative electrode tabs, which can be drawn from the same end of the main body portion 221, or can be drawn from two ends of the main body portion 221 opposite each other in the thickness direction of the first end cover assembly 24, respectively.

[0130] The tab 222 can include a plurality of tab layers stacked together to form the tab 222. The tab 222 can include at least two portions, one of which is located between the main body portion 221 and the isolation member 23, and the other of which is located between the isolation member 23 and the first electrode terminal 240.

[0131] The isolation member 23 can insulate at least part of the tab 222 from the end face of the main body portion 221, thereby reducing the risk of the tab 222 being inserted into the main body portion 221 when the battery cell 20 is affected by external impact, vibration, etc., and thus reducing the risk of short circuit of the battery cell 20, which is conducive to improving the reliability of the battery cell 20.

[0132] The isolation member 23 can be partially provided between the first electrode terminal 240 and the main body portion 221, or can be entirely provided between the first electrode terminal 240 and the main body portion 221.

[0133] The isolation member 23 can be a one-piece structure or a split structure. As an example, the isolation member 23 is connected by a plurality of independently formed parts. As another example, the isolation member 23 is integrally formed by stamping.

[0134] The first end cover assembly 24 is provided with a first clamping structure 5, and the isolation member 23 is provided with a second clamping structure 6. One of the first clamping structure 5 and the second clamping structure 6 has a clamping portion 501, and the other has a clamping groove portion 601, and the clamping portion 501 and the clamping groove portion 601 are clamped. In this way, the isolation member 23 can be fixedly connected to the first end cover assembly 24, thereby reducing the risk of the isolation member 23 moving in the battery cell 20, and further reducing the risk of the tab 222 being pulled or torn.

[0135] As an example, the first clamping structure 5 is a protruding structure protruding toward the electrode assembly 22 in the third direction, and the second clamping structure 6 is an opening structure corresponding to the protruding structure.

[0136] As another example, the second clamping structure 6 is a protruding structure protruding away from the electrode assembly 22 in the third direction, and the first clamping structure 5 is an opening structure corresponding to the protruding structure.

[0137] The third direction is a thickness direction of the first end cover assembly 24, for example, the z direction in FIG. 3.

[0138] The buckle part 501 has a first clamping surface, and the clamping groove part 601 has a second clamping surface. The size of the first clamping surface and the second clamping surface in the first direction is smaller than the size in the second direction.

[0139] The buckle part 501 and the clamping groove part 601 are clamped by the cooperation of the first clamping surface and the second clamping surface. The first clamping surface and the second clamping surface are both perpendicular to the third direction.

[0140] The size of the first clamping surface and the second clamping surface in the first direction can be the maximum size of the first clamping surface and the second clamping surface in the first direction, and the size of the first clamping surface and the second clamping surface in the second direction can be the maximum size of the first clamping surface and the second clamping surface in the second direction.

[0141] As an example, the second clamping surface of the clamping groove part 601 has a waist-round shape, and the first clamping surface of the buckle part 501 has a shape corresponding to the second clamping surface.

[0142] As another example, the second clamping surface of the clamping groove part 601 has a rectangular shape, and the first clamping surface of the buckle part 501 has a shape corresponding to the second clamping surface.

[0143] In the embodiments of the present application, the size of the first clamping surface in the first direction is smaller than the size of the first clamping surface in the second direction, and the size of the second clamping surface in the first direction is smaller than the size of the second clamping surface in the second direction.

[0144] Compared with the case where the size of the first clamping surface and the second clamping surface in the first direction and the second direction is the same (for example, the first clamping surface and the second clamping surface both have a circular shape), setting the size of the first clamping surface and the second clamping surface in the second direction to be larger than the size in the first direction is beneficial to increase the overlapping area between the first clamping surface and the second clamping surface, and the connection between the buckle part 501 and the clamping groove part 601 is more firm.

[0145] In addition, in the case where the isolation member 23 is provided with a passage through which the tab 222 passes, since the space of the isolation member 23 in the second direction is more spacious than the space in the first direction, the dimension of the second clamping surface along the first direction is less than the dimension of the second clamping surface along the second direction, which is also conducive to the processing of the clamping groove portion 601.

[0146] In the embodiments of the present application, the isolation member 23 is at least partially arranged between the first electrode terminal 240 and the main body portion 221, so that at least part of the tab 222 can be isolated from the main body portion 221 of the electrode assembly 22, thereby reducing the risk of the tab 222 being inserted into the main body portion 221 when the battery monomer 20 is impacted or the like, and reducing the risk of short circuit of the battery monomer 20. One of the first clamping structure 5 and the second clamping structure 6 has a clamping portion 501, and the other has a clamping groove portion 601, the clamping portion 501 is clamped with the clamping groove portion 601, thereby realizing the fixation between the first end cover assembly 24 and the isolation member 23. The clamping portion 501 has a first clamping surface, and the clamping groove portion 601 has a second clamping surface, the dimension of the first clamping surface and the second clamping surface along the first direction is less than the dimension along the second direction. In this way, it is conducive to increasing the overlapping area between the first clamping surface and the second clamping surface, the connection between the clamping portion 501 and the clamping groove portion 601 is more firm, so that the risk of the isolation member 23 moving in the battery monomer 20 can be reduced, and the risk of the tab 222 being pulled and torn can be reduced. Therefore, the technical scheme of the embodiments of the present application is conducive to improving the reliability of the battery monomer 20.

[0147] In some embodiments, the first clamping structure 5 is a protruding structure 50 protruding towards the electrode assembly 22 along a third direction, the protruding structure 50 comprises the clamping portion 501; the second clamping structure 6 is an opening structure 60 corresponding to the protruding structure 50, the opening structure 60 comprises the clamping groove portion 601, and the third direction is the thickness direction of the first end cover assembly 24.

[0148] As an example, the first end cover assembly 24 comprises an end cover 241 and an insulating piece 242, along the third direction, the insulating piece 242 is closer to the electrode assembly 22 relative to the end cover 241, and the insulating piece 242 has the protruding structure 50. Along the third direction, the protruding structure 50 protrudes towards the electrode assembly 22 relative to the end cover 241, and the opening structure 60 is arranged corresponding to the protruding structure 50. In this way, through the cooperation of the protruding structure 50 and the opening structure 60, the fixation and connection between the first end cover assembly 24 and the isolation member 23 are realized.

[0149] In the above embodiments, the clamping portion 501 of the protruding structure 50 is clamped into the clamping groove portion 601 of the opening structure 60, thereby realizing the connection between the first end cover assembly 24 and the isolation member 23; in addition, the first clamping structure 5 is the protruding structure 50, and the second clamping structure 6 is the opening structure 60, which is conducive to the processing of the first end cover assembly 24 and the isolation member 23.

[0150] FIG. 10 is a schematic view of a first profile according to an embodiment of the present application; and FIG. 11 is a schematic view of a second profile according to an embodiment of the present application.

[0151] In some embodiments, referring to FIGS. 10 and 11, the first clamping surface has a first profile 80, and the second clamping surface has a second profile 90. The first profile 80 includes a first straight line segment 81 extending in the second direction, and the second profile 90 includes a third straight line segment 91 extending in the second direction. The first profile 80 and the second profile 90 are perpendicular to the third direction.

[0152] As an example, the number of the first profiles 80 is 2, and the 2 first profiles 80 of the first clamping surface of the buckle portion 501 are symmetrical in the second direction. Each of the first profiles 80 includes the first straight line segment 81.

[0153] As an example, the number of the second profiles 90 is 1, and the second profile 90 includes 2 third straight line segments 91.

[0154] As an example, the first profile 80 is a rectangle, and the second profile 90 is a rectangle. In this way, the area of the overlapping region between the buckle portion 501 and the clamping portion 601 is larger, and the clamping between the buckle portion 501 and the clamping portion 601 is more secure.

[0155] As an example, the two first profiles 80 define a waist-round region, and the second profile 90 is waist-round. In this way, the area of the overlapping region between the buckle portion 501 and the clamping portion 601 is more appropriate, and it is also convenient for the assembly between the buckle portion 501 and the clamping portion 601.

[0156] In the case where the isolation member 23 is provided with a passage 2330 for the passage of the tab 222 in the middle region in the first direction, the space of the isolation member 23 in the second direction is more generous than the space in the first direction. In the first profile 80 and the second profile 90, it is more advantageous to provide the first straight line segment 81 and the third straight line segment 91 extending in the second direction for the processing of the buckle portion 501 and the clamping portion 601.

[0157] In the above embodiments, the first straight line segment 81 and the third straight line segment 91 extend in the second direction, which is convenient for the processing of the buckle portion 501 and the clamping portion 601, and also convenient for increasing the area of the overlapping region between the buckle portion 501 and the clamping portion 601, and improving the connection strength between the first end cover assembly 24 and the isolation member 23.

[0158] In some embodiments, the first profile 80 and the second profile 90 include at least one straight line segment.

[0159] At least one straight line segment in the first profile 80 corresponds to at least one straight line segment in the second profile 90, so that the first profile 80 and the second profile 90 have a relatively long overlapping length, the area of the overlapping region of the buckle portion 501 and the clamping groove portion 601 is relatively large, and the connection between the buckle portion 501 and the clamping groove portion 601 is relatively firm.

[0160] Compared with a circular profile, the first profile 80 and the second profile 90 include at least one straight line segment (for example, the length of the straight line segment is equal to the diameter of the circular profile), which is beneficial to increase the area of the overlapping region of the first clamping structure 5 and the second clamping structure 6, so that the clamping between the first clamping structure 5 and the second clamping structure 6 is more firm, the first clamping structure 5 is less likely to be separated from the second clamping structure 6, and the connection between the first end cover assembly 24 and the isolation member 23 is more firm. When the battery monomer is affected by factors such as vibration and extrusion, the risk of movement of the isolation member 23 is relatively low, the risk of pulling and tearing of the tab 222 is relatively low, and the battery monomer 20 has relatively high reliability.

[0161] In addition, compared with increasing the diameter of the circular profile, by providing at least one straight line segment in the first profile 80 and the second profile 90, it is also beneficial to keep the clamping groove portion at a suitable size, and the clamping groove portion 601 has a relatively suitable strength.

[0162] The first profile 80 and the second profile 90 can be a waist circle, a rectangle, a square, or other irregular polygons.

[0163] As an example, the first profile 80 and the second profile 90 each include two straight line segments, and the two straight line segments are parallel. For example, the cross-sectional profile of the clamping groove portion 601 is a waist circle, and the cross-sectional shape of the buckle portion 501 is a waist circle. For another example, in the case where the buckle portion 501 is provided with a deformation groove, the cross-sectional profile of the buckle portion 501 is two independent profiles, and the two independent profiles are spliced to form a waist circle.

[0164] In some embodiments, the length L1 of the first straight line segment 81 satisfies: 0.5mm≤L1≤5mm, and / or the length L2 of the third straight line segment 91 satisfies: 0.5mm≤L2≤5mm.

[0165] L1 can be 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 5mm, or any value within the above range; L2 can be 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 5mm, or any value within the above range.

[0166] As an example, L1 and L2 are the same.

[0167] When L1 and L2 are greater than or equal to 0.5 mm, the length of the overlapping area of the buckle portion 501 and the clamping groove portion 601 in the second direction is large, the overlapping area has a large area, the buckle portion 501 and the clamping groove portion 601 have a strong clamping strength, and the buckle portion 501 has a high structural strength; when L1 and L2 are less than or equal to 5 mm, the clamping groove portion 601 has a suitable size, which can reduce the adverse effects on the strength of the clamping groove portion 601 due to the excessively large size of the clamping groove portion 601 in the second direction, and the clamping groove portion 601 has a high structural strength.

[0168] In the above embodiments, 0.5 mm≤L1≤5 mm, and / or, 0.5 mm≤L2≤5 mm, L1 and L2 have suitable sizes, the overlapping area between the buckle portion 501 and the clamping groove portion 601 has a large area, the connection strength between the first end cover assembly 24 and the isolation member 23 is large, which is beneficial to reduce the risk of the isolation member 23 moving in the battery monomer 20 and the tab 222 tearing, and the buckle portion 501 and the clamping groove portion 601 have a high structural strength, and the battery monomer 20 has a high reliability.

[0169] In some embodiments, 2 mm≤L1≤4 mm, and / or, 2 mm≤L2≤4 mm. In this way, the connection strength between the first end cover assembly 24 and the isolation member 23 is suitable, and the buckle portion 501 and the clamping groove portion 601 have a high structural strength, and the battery monomer 20 has a high reliability.

[0170] In some embodiments, the first contour 80 includes a first arc segment 82 and a second arc segment 83, and the first arc segment 82 and the second arc segment 83 are connected with two ends of the first straight line segment 81, respectively.

[0171] As an example, the first contour 80 further includes a second straight line segment 84, the second straight line segment 84 is perpendicular to the first straight line segment 81, and the first straight line segment 81, the first arc segment 82, the second straight line segment 84, the first arc segment 82, the first straight line segment 81, the second arc segment 83, the second straight line segment 84, and the second arc segment 83 are sequentially connected to form the first contour 80.

[0172] Compared with all straight line segments in the first contour 80, the first arc segment 82 and the second arc segment 83 are beneficial to the processing of the buckle portion 501 and facilitate the buckle portion 501 to enter the clamping groove portion 601.

[0173] In some embodiments, the radius R1 of the first arc segment 82 and the second arc segment 83 satisfies: 0.3 mm≤R1≤2.5 mm.

[0174] The first arc segment 82 and the second arc segment 83 can be the same arc segment.

[0175] R1 can be 0.3mm, 0.5mm, 0.8mm, 1mm, 1.5mm, 2mm, 2.1mm, 2.5mm, or any value within the above range.

[0176] As an example, the first arc segment 82 and the second arc segment 83 are quarter circular arcs. In this way, when R1 satisfies the above range, the first arc segment 82 and the second arc segment 83 can be well matched with the length of the first straight segment 81, facilitating the processing of the buckle portion 501.

[0177] In the above embodiment, 0.3mm≤R1≤2.5mm, the first arc segment 82 and the second arc segment 83 have appropriate sizes, facilitating the processing of the buckle portion 501 and the smooth entry of the buckle portion 501 into the clamping groove portion 601.

[0178] In some embodiments, 1.0mm≤R1≤2.1mm. In this way, the first arc segment 82 and the second arc segment 83 have appropriate sizes, facilitating the processing of the buckle portion 501 and the smooth entry of the buckle portion 501 into the clamping groove portion 601.

[0179] In some embodiments, the second profile 90 includes a third arc segment 92 and a fourth arc segment 93, which are respectively connected with two ends of the third straight segment 91.

[0180] As an example, the second profile 90 includes two third straight segments 91, a third arc segment 92 and a fourth arc segment 93, wherein the third straight segment 91, the third arc segment 92, the third straight segment 91, and the fourth arc segment 93 are sequentially connected.

[0181] In the above embodiment, by setting the third arc segment 92 and the fourth arc segment 93, the processing of the clamping groove portion 601 is facilitated, and the buckle portion 501 is facilitated to enter the clamping groove portion 601.

[0182] In some embodiments, the radius R2 of the third arc segment 92 and the fourth arc segment 93 satisfies: 0.5mm≤R2≤2.7mm.

[0183] The third arc segment 92 and the fourth arc segment 93 can be the same arc segment.

[0184] R2 can be 0.5mm, 0.8mm, 1mm, 1.3mm, 1.5mm, 1.8mm, 2mm, 2.1mm, 2.3mm, 2.5mm, 2.7mm, or any value within the above range.

[0185] As an example, the third arc segment 92 and the fourth arc segment 93 are semicircular arcs. In this way, the length of the third arc segment 92 and the fourth arc segment 93 can be matched with the length of the third straight segment 91, facilitating the processing of the clamping groove portion 601.

[0186] The radii of the third arc segment 92 and the fourth arc segment 93 are greater than the radii of the first arc segment 82 and the second arc segment 83, so that the buckle portion 501 is smoothly inserted into the clamping groove portion 601.

[0187] In the above embodiment, the third arc segment 92 and the fourth arc segment 93 have appropriate sizes, facilitating the processing of the clamping groove portion 601 and the smooth insertion of the buckle portion 501 into the clamping groove portion 601.

[0188] In some embodiments, 1.2 mm≤R2≤2.3 mm. In this way, the third arc segment 92 and the fourth arc segment 93 have appropriate sizes, facilitating the processing of the clamping groove portion 601 and the smooth insertion of the buckle portion 501 into the clamping groove portion 601.

[0189] In some embodiments, the size L3 of the overlapping area of the buckle portion 501 and the clamping groove portion 601 along the first direction satisfies: 0.15 mm≤L3≤0.5 mm, and the first direction is the length direction of the isolation member 23.

[0190] For example, as shown in FIGS. 3-9, the first direction is the x direction.

[0191] L3 can be 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.4 mm, 0.5 mm, or any value within the above range.

[0192] In the case where L3 is greater than or equal to 0.15 mm, the size of the overlapping area of the buckle portion 501 and the clamping groove portion 601 in the first direction is relatively large, the area of the overlapping area between the buckle portion 501 and the clamping groove portion 601 is relatively large, and the buckle portion 501 is not easy to be separated from the clamping groove portion 601; in the case where L3 is less than or equal to 0.5 mm, the buckle portion 501 is facilitated to be inserted into the clamping groove portion 601.

[0193] In the above embodiment, 0.15 mm≤L3≤0.5 mm, the overlapping area between the buckle portion 501 and the clamping groove portion 601 has a relatively large area, the connection strength between the first end cover assembly 24 and the isolation member 23 is relatively large, the risk of the isolation member 23 moving in the battery monomer 20 and the risk of the tab 222 tearing are relatively low, and the battery monomer 20 has relatively high reliability; in addition, it is also facilitated that the buckle portion 501 is inserted into the clamping groove portion 601.

[0194] In some embodiments, 0.2 mm≤L3≤0.4 mm. In this way, the overlapping area of the buckle portion 501 and the clamping groove portion 601 has a more appropriate size in the first direction, which facilitates the insertion of the buckle portion 501 into the clamping groove portion 601 and prevents the buckle portion 501 from being separated from the clamping groove portion 601.

[0195] FIG. 12 is a structural schematic diagram of a first end cover assembly according to an embodiment of the present application; FIG. 13 is an enlarged schematic diagram of region E in FIG. 12; FIG. 14 is a structural schematic diagram of a separation member according to an embodiment of the present application; FIG. 15 is a top view of the separation member according to an embodiment of the present application; FIG. 16 is a schematic diagram of a protruding structure according to an embodiment of the present application; and FIG. 17 is a schematic diagram of an opening structure according to an embodiment of the present application.

[0196] In some embodiments, as shown in FIGS. 7-17, the protruding structure 50 includes a buckle portion 501, a connecting portion 502, and a transition portion 503, the connecting portion 502 is connected to the transition portion 503 and the buckle portion 501 at two ends thereof along a third direction; the opening structure 60 includes a clamping groove portion 601, a guide portion 603, and a limiting portion 602, the limiting portion 602 is connected to the guide portion 603 and the clamping groove portion 601 at two ends thereof along the third direction.

[0197] As an example, the guide portion 603 gradually decreases in size in the first direction along the third direction and in a direction pointing to the electrode assembly 22; correspondingly, the transition portion 503 gradually decreases in size in the first direction along the third direction and in a direction pointing to the electrode assembly 22. The guide portion 603 and the transition portion 503 are matched, and the guide portion 603 can guide the protruding structure 50 to enter the opening structure 60.

[0198] As an example, the limiting portion 602 is constant in size in the first direction along the third direction, and the connecting portion 502 is constant in size in the first direction. For example, the limiting portion 602 is a cylindrical through hole, and the connecting portion 502 is a cylindrical structure.

[0199] The buckle portion 501 is connected to the connecting portion 502, and the buckle portion 501 protrudes from the connecting portion 502 in the first direction. The first direction is the length direction of the separation member 23, for example, the x direction in FIGS. 3-8. In this way, the buckle portion 501 is facilitated to be limited in the clamping groove portion 601.

[0200] In the above embodiments, the guide portion 603 can guide the protruding structure 50 to enter the opening structure 60, and the limiting portion 602 can limit the movement of the buckle portion 501 along the third direction after the buckle portion 501 of the protruding structure 50 enters the clamping groove portion 601, thereby reducing the risk of the buckle portion 501 from separating from the clamping groove portion 601.

[0201] In some embodiments, along the first direction, the size D1 of the limiting portion 602, the size D2 of the connecting portion 502, and the size D3 of the buckle portion 501 satisfy: D2 < D1 < D3.

[0202] D1 can be the maximum size of the limiting portion 602 in the first direction, D2 can be the maximum size of the connecting portion 502 in the first direction, and D3 can be the maximum size of the buckle portion 501 in the first direction.

[0203] In the first direction, the size of the limiting portion 602 is smaller than the size D3 of the clamping portion 501 and larger than the size of the connecting portion 502, so that after the clamping portion 501 enters the clamping groove portion 601, the limiting portion 602 can limit the clamping portion 501 from moving away from the clamping groove portion 601 in the third direction.

[0204] In the above embodiment, the arrangement of the guiding portion 603 can guide the protruding structure 50 to enter the opening structure 60, and the arrangement of the limiting portion 602 can limit the movement of the clamping portion 501 in the third direction after the clamping portion 501 of the protruding structure 50 enters the clamping groove portion 601, thereby reducing the risk of the clamping portion 501 moving away from the clamping groove portion 601.

[0205] In some embodiments, 0.05mm≤D1-D2≤1mm.

[0206] D1-D2 can be 0.05mm, 0.1mm, 0.3mm, 0.35mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, 1mm or any value within the above range.

[0207] In the case of D1-D2 greater than or equal to 0.05mm, the connecting portion 502 is facilitated to pass through the limiting portion 602; in the case of D1-D2 less than or equal to 1mm, the size difference between the connecting portion 502 and the limiting portion 602 in the first direction has a suitable range, which can reduce the size of the limiting portion 602 in the first direction, increase the structural strength of the opening structure 60, and further reduce the risk of the clamping portion 501 moving away from the limiting portion after being clamped into the clamping groove portion 601.

[0208] In the above embodiment, 0.05mm≤D1-D2≤1mm, the limiting portion 602 of the opening structure 60 and the connecting portion 502 of the protruding structure 50 have suitable sizes, which can not only make the connecting portion 502 pass through the limiting portion 602 to enter the clamping groove portion 601, but also reduce the risk of the clamping portion 501 moving away from the clamping groove portion 601.

[0209] In some embodiments, 0.4mm≤D1-D2≤0.6mm. In this way, the limiting portion 602 of the opening structure 60 and the connecting portion 502 of the protruding structure 50 have suitable sizes, which can not only make the connecting portion 502 pass through the limiting portion 602 to enter the clamping groove portion 601, but also reduce the risk of the clamping portion 501 moving away from the clamping groove portion 601.

[0210] In some embodiments, the protruding structure 50 includes a deformation groove 504, the deformation groove 504 extends through the clamping portion 501 and at least part of the connecting portion 502 in the third direction, and the width direction of the deformation groove 504 is perpendicular to the second direction.

[0211] As an example, the deformation groove 504 is a groove with an opening facing the electrode assembly 22, and the deformation groove 504 penetrates the buckle portion 501 and the connecting portion 502 along the third direction.

[0212] The sidewall of the deformation groove 504 can have an angle with the third direction, or can be parallel to the third direction, or a part of the sidewall is parallel to the third direction and another part has an angle with the third direction.

[0213] Through the arrangement of the deformation groove 504, the buckle portion 501 and the connecting portion 502 can be deformed along the first direction, specifically, the size of the buckle portion 501 and the connecting portion 502 in the first direction can be reduced, so that the buckle portion 501 passes through the limiting portion 602 and is clamped into the clamping groove portion 601 in the process of clamping the protruding structure 50 into the opening structure 60.

[0214] In some embodiments, along the first direction, the size D4 of the deformation groove 504 satisfies: 0.3mm≤D4≤1.5mm.

[0215] D4 can be 0.3mm, 0.5mm, 0.6mm, 0.7mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.5mm or any value within the above range.

[0216] As an example, the size D4 of the deformation groove 504 in the first direction can be the size of the deformation groove 504 in the first direction at the position corresponding to the connection between the buckle portion 501 and the connecting portion 502.

[0217] In the case of D4 greater than or equal to 0.3mm, in the process of clamping the buckle portion 501 into the clamping groove portion 601, the size of the buckle portion 501 in the first direction can be reduced within a certain range, so that the buckle portion 501 passes through the limiting portion 602 and then enters the clamping groove portion 601; in the case of D4 less than or equal to 1.5mm, the deformation groove 504 has a suitable size in the first direction, which can reduce the reduction of the strength of the connecting portion 502 and the buckle portion 501 due to the too large size of the deformation groove 504 in the first direction, and the protruding structure 50 has a suitable strength.

[0218] In the above embodiments, the deformation groove 504 has a suitable size in the first direction, which is beneficial to the assembly of the first end cover assembly 24 and the isolation member 23, and the protruding structure 50 has a relatively suitable strength, which is beneficial to the assembly of the battery monomer 20 and the improvement of the reliability of the battery monomer 20.

[0219] In some embodiments, 0.7mm≤D4≤1.1mm. In this way, the deformation groove 504 has a suitable size in the first direction, facilitating the smooth clamping of the buckle part 501 into the clamping groove part 601 while taking into account the strength of the protruding structure 50, and being conducive to the assembly of the battery monomer 20 and the improvement of the reliability of the battery monomer 20.

[0220] In some embodiments, the second profile 90 is a waist-round shape.

[0221] In this way, the overlapping area between the clamping groove part 601 and the buckle part 501 has a larger area and facilitates the clamping of the protruding structure 50 into the opening structure 60, thereby facilitating the assembly between the first end cover assembly 24 and the isolation member 23 and the improvement of the connection strength between the two.

[0222] In some embodiments, the protruding structure 50 includes a first fixed part 505 connected with the transition part 503 and away from the electrode assembly 22 in the third direction relative to the transition part 503; the opening structure 60 includes a second fixed part 604 connected with the guide part 603 and away from the electrode assembly 22 in the third direction relative to the guide part 603; the first fixed part 505 and the second fixed part 604 abut. In this way, through the abutment of the first fixed part 505 and the second fixed part 604, the fixation of the protruding structure 50 and the opening structure 60 in the first direction can be achieved.

[0223] In some embodiments, the first end cover assembly 24 is provided with two first clamping structures 5, and the two first clamping structures 5 are respectively arranged at the end regions of the first end cover assembly 24 in the first direction, and the first direction is the length direction of the isolation member 23; the isolation member 23 is provided with two second clamping structures 6, and the two second clamping structures 6 are respectively arranged at the end regions of the isolation member 23 in the first direction.

[0224] In the above technical solution, the two first clamping structures 5 and the two second clamping structures 6 are arranged, which is conducive to increasing the connection strength between the first end cover assembly 24 and the isolation member 23. In addition, the second clamping structure 6 is arranged at the end region of the isolation member 23 in the first direction, which facilitates the arrangement of the passage for the tab 222 to pass through in the middle region of the isolation member 23, so as to facilitate the connection between the tab 222 and the first electrode terminal 240.

[0225] In some embodiments, the isolation member 23 is provided with a passage 2330 arranged at the middle region of the isolation member 23 in the first direction, and the tab 222 passes through the passage and is electrically connected with the first electrode terminal 240.

[0226] In the technical solution, the channel 2330 is arranged at the middle region of the isolation member 23 along the first direction, and the channel 2330 is convenient for corresponding to the tab 222 and convenient for the tab 222 to pass through the channel 2330 and electrically connect with the first electrode terminal 240.

[0227] In some embodiments, the first end cover assembly 24 includes an end cover 241 and an insulating piece 242, the end cover 241 is used to cover the first opening 211, and the insulating piece 242 is provided with the first clamping structure 5.

[0228] The insulating piece 242 is used to isolate the end cover 241 and the electrode assembly 22, and the insulating piece 242 can be an integral molding structure with the first clamping structure 5.

[0229] The first electrode terminal 240 can be arranged on the end cover 241, and the tab 222 of the electrode assembly 22 passes through the channel 2330 of the isolation member 23 and is connected with the first electrode terminal 240.

[0230] The end cover 241 can be made of metal and can conduct electricity, and the insulating piece 242 can be a plastic product.

[0231] In the above embodiments, the end cover 241 covers the first opening 211 of the shell 21, and the first electrode terminal 240 on the end cover is electrically connected with the tab 222, and the first clamping structure 5 of the insulating piece is clamped with the second clamping structure 6 of the isolation member 23. Through the arrangement of the first end cover assembly 24, the connection of the first end cover assembly 24, the isolation member 23 and the electrode assembly 22 is facilitated.

[0232] In some embodiments, the battery monomer 20 further includes a second end cover assembly 25, and the second end cover assembly 25 is used to cover the opening at the other end of the shell 21.

[0233] The shell 21 can be a hollow structure with openings at both ends, and the first end cover assembly 24 and the second end cover assembly 25 cover the openings at both ends of the shell 21 respectively.

[0234] Specifically, the first end cover assembly 24 and the second end cover assembly 25 are oppositely arranged along the thickness direction of the first end cover assembly 24, the shell 21 is provided with the first opening 211 and the second opening 212 which are opposite along the thickness direction of the isolation plate 231, the first opening 211 is arranged at one end close to the isolation member 23 along the thickness direction of the first end cover assembly 24, and the second opening 212 is arranged at one end away from the isolation member 23 along the thickness direction of the first end cover assembly 24. The first end cover assembly 24 is used to cover the first opening 211, and the second end cover assembly 25 is used to cover the second opening 212. As an example, the second end cover assembly 25 is further provided with a second electrode terminal 251, and the polarity of the second electrode terminal 251 is opposite to that of the first electrode terminal 240 arranged on the first end cover assembly 24.

[0235] As an example, the second end cover assembly 25 has a different structure from the first end cover assembly 24, and the second end cover assembly 25 is not provided with the protrusion matched with the opening structure.

[0236] In some embodiments, the isolation member 23 comprises a side wall 230 and an isolation plate 231, the side wall 230 comprises a first side wall 2301 and a second side wall 2302, the first side wall 2301 extends along a first direction, and the second side wall 2302 extends along a second direction, and the opening structure 60 is protruded on the isolation plate 231.

[0237] In some embodiments, the channel 2330 is provided on the isolation plate 231.

[0238] In some embodiments, the isolation member 23 further comprises a reinforcing structure 232, the reinforcing structure 232 is connected to the outer side wall of the opening structure 60 and the side wall 230. As an example, the reinforcing structure 232 is connected to the outer side wall of the opening structure 60 and the first side wall 2301. By providing the reinforcing structure 232, the strength of the opening structure 60 can be enhanced, and the risk of deformation of the opening structure 60 and the risk of disengagement of the protruding structure 50 from the opening structure 60 can be reduced.

[0239] In some embodiments, the isolation plate 231 is provided with a through hole 237. For example, along the second direction, the end region of the isolation plate 231 is provided with the through hole 237. By providing the through hole 237, the accumulation of electrolyte in the isolation member 23 can be facilitated.

[0240] In some embodiments, the battery monomer 20 further comprises an insulating film 26, the insulating film 26 is sleeved on the outer surface of the electrode assembly 22 and is provided on the inner side of the shell 21. In this way, the electrode assembly 22 can be isolated from the shell 21, and the risk of short circuit caused by contact between the electrode assembly 22 and the shell 21 can be reduced; in addition, the isolation member 23 can be connected to the electrode assembly 22 through the insulating film 26, thereby facilitating the assembly of the battery monomer 20.

[0241] As an example, the insulating film 26 is an insulating and thermoplastic isolation film, such as a mylar film.

[0242] In some embodiments, the battery monomer 20 further comprises a side support plate 27, the side support plate 27 is provided between the electrode assembly 22 and the inner side of the shell 21. The side support plate 27 can support the electrode assembly 22; and the electrode assembly 22 and the isolation member 23 can be connected through the side support plate 27, thereby facilitating the assembly of the battery monomer 20.

[0243] In some embodiments, the battery cell 20 includes a pressure relief mechanism. The pressure relief mechanism can be provided on the housing 21, the first end cap assembly 24, or the second end cap assembly 25. The pressure relief mechanism is used to vent the internal discharge of the battery cell, including but not limited to: electrolyte, dissolved or split positive and negative electrode sheets, fragments of the separator, high temperature and pressure gas generated by the reaction, flame, etc.

[0244] As an example, the pressure relief mechanism is actuated to release the internal pressure or temperature when the internal pressure or temperature of the battery cell 20 reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 20 reaches the predetermined threshold, the pressure relief mechanism performs an action or a weak structure provided in the pressure relief mechanism is broken, thereby forming an opening or passage for the internal pressure or temperature to be released. The threshold is designed differently according to the design requirements. The threshold can depend on the material of one or more of the positive electrode sheet, the negative electrode sheet, the electrolyte, and the separator in the battery cell.

[0245] According to some embodiments of the present application, the present application also provides a battery apparatus comprising the battery cell 20 of any of the above-mentioned aspects.

[0246] The battery apparatus mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells 20 connected in series, in parallel, or in a mixed connection through a busbar component.

[0247] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells 20.

[0248] As an example, the battery cell assembly can be a battery module formed by arranging and fixing a plurality of battery cells into an independent module. As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0249] In some embodiments, the battery apparatus can be a battery pack including a box and one or more battery cell assemblies accommodated in the box.

[0250] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the box by fixing the battery module in the box.

[0251] As an example, the battery cell assembly can also be accommodated in the box by directly fixing a plurality of battery cells in the box.

[0252] As an example, the box can include a first box and a second box. The first box and the second box are buckled so that the inside of the box forms a closed space to accommodate the battery monomer assembly. The closed here means covered or closed, which can be sealed or non-sealed. The first box can be a top cover or a bottom plate.

[0253] As an example, the box can include a top cover, a frame and a bottom plate. The top cover and the bottom plate are connected with the frame respectively, so that the inside of the box forms a closed space to accommodate the battery monomer assembly.

[0254] In some embodiments, the box can be part of the chassis structure of the vehicle. For example, part of the box can be at least part of the floor of the vehicle, or part of the box can be at least part of the cross beam and the longitudinal beam of the vehicle.

[0255] According to some embodiments of the present application, the present application also provides an electrical equipment, which includes the battery device of any of the above solutions, and the battery device is used to provide electrical energy for the electrical equipment.

[0256] The electrical equipment can be the equipment or system of any of the above applications of the battery device.

[0257] According to some embodiments of the present application, referring to FIGS. 3-16, the present application provides a battery monomer 20, which includes a shell 21, a first end cover assembly 24, an electrode assembly 22 and a separation member 23. The separation member 23 is at least partially arranged between the first electrode terminal 240 and the main body part 221, so as to separate at least part of the tab 222 from the main body part 221 of the electrode assembly 22, thereby reducing the risk of the tab 222 being inserted into the main body part 221 when the battery monomer 20 is impacted or the like, and reducing the risk of short circuit of the battery monomer 20. The first end cover assembly 24 is provided with a protruding structure 50 protruding towards the electrode assembly 22, and the separation member 23 is provided with an opening structure 60 corresponding to the protruding structure 50. The protruding structure 50 includes a buckle part 501, and the opening structure 60 includes a clamping groove part 601. The buckle part 501 is clamped into the clamping groove part 601 to realize the fixation of the first end cover assembly 24 and the separation member 23. The cross section of the clamping groove part 601 is profiled as a waist circle, and the number of profiles of the cross section of the buckle part 501 is two, and the two profiles are symmetrically arranged along the width direction of the separation member 23, and the two profiles are spliced as a waist circle. The cross section is perpendicular to the thickness direction of the first end cover assembly 24. In this way, the area of the overlapping area between the first clamping structure 5 and the second clamping structure 6 can be increased, the risk of the first clamping structure 5 being separated from the second clamping structure 6 can be reduced, and the connection strength between the first clamping structure 5 and the second clamping structure 6 can be increased, thereby the risk of the separation member 23 moving in the battery monomer 20 can be reduced, and the risk of the tab 222 being pulled and torn can be reduced.

[0258] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some or all of the technical features can be replaced equivalently. Such modifications or replacements do not change the essence of the corresponding technical solutions, which should be covered in the scope of the claims and the specification of the present application. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized by, Comprise: a first end cover assembly (24) comprising a first electrode terminal (240); an electrode assembly (22) comprising a main body portion (221) and a tab (222) extending from the main body portion (221); an isolation member (23) disposed at least partially between the first electrode terminal (240) and the main body portion (221); wherein the first end cover assembly (24) is provided with a first clamping structure (5), the isolation member (23) is provided with a second clamping structure (6), one of the first clamping structure (5) and the second clamping structure (6) has a clamping buckle portion (501), the other has a clamping slot portion (601), the clamping buckle portion (501) and the clamping slot portion (601) are clamped, the clamping buckle portion (501) has a first clamping surface, the clamping slot portion (601) has a second clamping surface, the first clamping surface and the second clamping surface have a dimension along a first direction smaller than a dimension along a second direction, the first direction is a length direction of the isolation member (23), and the second direction is a width direction of the isolation member (23).

2. The battery cell of claim 1, wherein, The first clamping structure (5) is a protruding structure (50) protruding toward the electrode assembly (22) along a third direction, the protruding structure (50) comprises the clamping buckle portion (501), and the second clamping structure (6) is an opening structure (60) corresponding to the protruding structure (50), the opening structure (60) comprises the clamping slot portion (601), and the third direction is a thickness direction of the first end cover assembly (24).

3. The battery cell of claim 2, wherein, The first clamping surface has a first profile (80), and the first profile (80) comprises a first straight line segment (81) extending along the second direction; The second clamping surface has a second profile (90), and the second profile (90) comprises a third straight line segment (91) extending along the second direction; The first profile (80) and the second profile (90) are perpendicular to the third direction.

4. The battery cell of claim 3, wherein, The length L1 of the first straight line segment (81) satisfies: 0.5mm≤L1≤5mm, and / or the length L2 of the third straight line segment (91) satisfies: 0.5mm≤L2≤5mm.

5. The battery cell of claim 4, wherein, 2mm≤L1≤4mm, and / or 2mm≤L2≤4mm.

6. The battery cell according to claim 3 or 4, characterized in that, The first profile (80) comprises a first arc line segment (82) and a second arc line segment (83), and the first arc line segment (82) and the second arc line segment (83) are connected to both ends of the first straight line segment (81) respectively.

7. The battery cell of claim 6, wherein, The radius R1 of the first arc line segment (82) and the second arc line segment (83) satisfies: 0.3mm≤R1≤2.5mm.

8. The battery cell of claim 7, wherein, 1.0mm≤R1≤2.1mm.

9. The battery cell of any one of claims 6-8, wherein, The first profile (80) comprises a second straight line segment (84) parallel to the first direction, and two ends of the first arc line segment (82) are connected to the first straight line segment (81) and the second straight line segment (84) respectively.

10. The battery cell of any one of claims 3-9, wherein, The second profile (90) comprises a third arc line segment (92) and a fourth arc line segment (93) connected to two ends of the third straight line segment (91) respectively.

11. The battery cell of claim 10, wherein, The radii R2 of the third arc line segment (92) and the fourth arc line segment (93) satisfy: 0.5mm≤R2≤2.7mm.

12. The battery cell of claim 11, wherein, 1.2mm≤R2≤2.3mm.

13. The battery cell of any one of claims 1-12, wherein, Along the first direction, the size L3 of the overlapping area of the buckle part (501) and the card slot part (601) satisfies: 0.15mm≤L3≤0.5mm.

14. The battery cell of claim 13, wherein, 0.2mm≤L3≤0.4mm.

15. The battery cell of any one of claims 2-14, wherein, The protruding structure (50) comprises the buckle part (501), a connecting part (502), and a transition part (503), two ends of the connecting part (502) along the third direction are connected to the transition part (503) and the buckle part (501) respectively; The opening structure (60) comprises the card slot part (601), a limiting part (602), and a guide part (603), two ends of the limiting part (602) along the third direction are connected to the guide part (603) and the card slot part (601) respectively.

16. The battery cell of claim 15, wherein, Along the first direction, the size D1 of the limiting part (602), the size D2 of the connecting part (502), and the size D3 of the buckle part (501) satisfy: D2<D1<D3.

17. The battery cell of claim 16, wherein, 0.05mm≤D1-D2≤1mm.

18. The battery cell of claim 17, wherein, 0.4mm≤D1-D2≤0.6mm.

19. The battery cell of any one of claims 15-18, wherein, The protruding structure (50) comprises a deformation groove (504) penetrating through the buckle part (501) and at least part of the connecting part (502) along the third direction, and the width direction of the deformation groove (504) is perpendicular to the second direction.

20. The battery cell of claim 19, wherein, Along the first direction, the size D4 of the deformation groove satisfies: 0.3mm≤D4≤1.5mm.

21. The battery cell of claim 20, wherein, 0.7mm≤D4≤1.1mm.

22. The battery cell of any one of claims 1-21, wherein, The first end cover assembly (24) is provided with two first clamping structures (5), and the two first clamping structures (5) are arranged at the end regions of the first end cover assembly (24) along the first direction respectively. The isolation member (23) is provided with two second clamping structures (6), and the two second clamping structures (6) are arranged at the end regions of the isolation member (23) along the first direction respectively.

23. The battery cell of any one of claims 1-22, wherein, The isolation member (23) is provided with a channel (2330) arranged at the middle region of the isolation member (23) along the first direction, and the tab passes through the channel (2330) and is electrically connected to the first electrode terminal (240).

24. The battery cell of any one of claims 1-23, wherein, The battery monomer comprises a shell (21) having a first opening (211); The first end cap assembly (24) comprises an end cap for closing the first opening (211) and an insulation piece (242) provided with the first clamping structure (5).

25. A battery device, characterized by Comprising: A plurality of battery cells according to any one of claims 1-24.

26. An electrical device, comprising: Comprising: The battery device according to claim 25 or a plurality of battery cells according to any one of claims 1-24, the battery cells or the battery device being used for storing or providing electrical energy.

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