Battery cells, batteries and power consuming devices

Abstract

This application discloses a battery cell, a battery, and a power consumption device. The battery cell includes an outer case, an electrode assembly, and an electrode terminal. The outer case includes a wall portion with an electrode lead-out hole. At least a portion of the electrode assembly is housed within the outer case, and the electrode assembly includes a tab. The electrode terminal is installed on the wall portion and covers at least a portion of the electrode lead-out hole. The electrode terminal is electrically connected to the tab. The electrode terminal is deformable when the internal pressure or temperature of the outer case reaches a threshold value, thereby communicating the interior space and the exterior space of the outer case through the electrode lead-out hole.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to a Chinese patent application entitled "Battery Cell, Battery and Power Consumption Device," application number 202310389480.4, filed on April 12, 2023, the entire contents of which are incorporated herein by reference. [Technical Field]

[0002] This application relates to the field of batteries, and more particularly to battery cells, batteries and power consuming devices. [Background technology]

[0003] With the development of battery technology, battery cells are being used in more and more fields, and are gradually replacing traditional petrochemical energy in the field of automotive power. Battery cells can store chemical energy and then controllably convert the chemical energy into electrical energy. Reusable battery cells can be discharged and then recharged to activate the active material and continue use.

[0004] How to improve the reliability of battery cells is an important research vector in the industry. Summary of the Invention

[0005] The present application provides a battery cell, a battery, and a power consuming device that can improve their reliability.

[0006] In a first aspect, the present application provides a battery cell including an outer case, an electrode assembly, and an electrode terminal. The outer case includes a wall portion having an electrode lead-out hole. At least a portion of the electrode assembly is housed within the outer case, and the electrode assembly includes a tab. The electrode terminal is attached to the wall portion and covers at least a portion of the electrode lead-out hole. The electrode terminal is electrically connected to the tab. As a result, the interior and exterior spaces of the outer case are in communication through the electrode lead-out hole, and at least a portion of the electrode terminal is deformable when the internal pressure or temperature of the outer case reaches a threshold value so as to exhaust gas within the outer case.

[0007] When the internal pressure or temperature of the outer case reaches a threshold, the above technical solution utilizes the deformation of the electrode terminals to connect the internal space of the outer case with the external space, thereby releasing the internal gas and pressure of the outer case and reducing the risk of the battery cell exploding. Compared with solutions that require an additional pressure reducing mechanism to be installed in the outer case, the above technical solution can simplify the structure of the battery cell and reduce the cost of the battery cell.

[0008] In some embodiments, at least a portion of the electrode terminal is capable of detaching from the wall when the internal pressure or temperature of the outer case reaches a threshold value.

[0009] When at least a portion of the electrode terminal is detached from the wall portion, at least a portion of the electrode pull-out hole is no longer covered by the electrode terminal, and the electrode pull-out hole can communicate between the internal space of the outer case and the external space, thereby releasing the internal gas of the battery cell and reducing the internal pressure and temperature of the battery cell.

[0010] In some embodiments, the electrode terminal includes a protrusion that protrudes from the wall of the electrode lead-out hole along the radial direction of the electrode lead-out hole, the protrusion being located on the side of the wall facing the electrode assembly, and the protrusion being deformable when the internal pressure or temperature of the outer case reaches a threshold value.

[0011] While the battery cell is operating normally, the wall can stop the protrusion, thereby reducing the risk of the electrode terminal escaping through the electrode lead-out hole. When the internal pressure or temperature of the outer case reaches a threshold, the protrusion is deformable, so that the wall no longer stops the protrusion, allowing the electrode terminal to escape through the electrode lead-out hole, communicating the internal space and external space of the outer case through the electrode lead-out hole and allowing gas inside the outer case to be exhausted through the electrode lead-out hole, reducing the risk of the battery cell exploding.

[0012] In some embodiments, when the maximum dimension of the protrusion protruding from the wall of the electrode lead hole is L1 and the minimum distance between the periphery of the wall portion and the wall of the electrode lead hole is L2, L1 and L2 satisfy 0.1≦L1 / L2≦0.5.

[0013] By limiting the L1 / L2 ratio to 0.5 or less, the outer case can deform immediately when the internal pressure or temperature reaches a threshold, improving the reliability of the battery cell.By limiting the L1 / L2 ratio to 0.1 or more, the stability of the electrode terminals on the wall can be improved, reducing the risk of the electrode terminals falling off when the battery cell is subjected to external impact.

[0014] In some embodiments, when the maximum dimension of the protrusion protruding from the wall of the electrode lead hole is L1 and the maximum thickness of the protrusion is T1, L1 and T1 are 0.25 mm 2 ≦L1×T1≦25mm 2 Meet the following.

[0015] Set the value of L1×T1 to 25mm 2 By limiting the value of L1 x T1 to 0.25mm or less, the battery cell can deform immediately when the internal pressure or temperature of the outer case reaches a threshold, improving the reliability of the battery cell. 2 By limiting the above, the stability of the electrode terminals on the wall portion can be improved, and the risk of the electrode terminals falling off when the battery cell receives an external impact can be reduced.

[0016] In some embodiments, T1 is between 0.5 mm and 5 mm. By limiting T1 to between 0.5 mm and 5 mm, the outer case can be deformed immediately when the internal pressure or temperature of the outer case reaches a threshold, and the risk of the electrode terminals falling off when the battery cell is subjected to an external impact is reduced.

[0017] In some embodiments, the thickness of at least a portion of the protrusion gradually decreases in a direction from the central axis of the electrode lead-out hole toward the outer circumferential edge of the protrusion.

[0018] By providing the protrusion with a thickness transition region where the thickness gradually decreases, the protrusion is more easily deformed under the action of internal pressure, thereby quickly reducing pressure and improving the reliability of the battery cell.

[0019] In some embodiments, the protrusion has a first surface facing the wall, the wall has a second surface facing the protrusion, the second surface is perpendicular to the thickness direction of the wall, the first surface is inclined relative to the second surface in a direction approaching the electrode assembly, and the distance in the thickness direction of the wall between one end of the first surface away from the electrode lead hole and the second surface is greater than the distance between one end of the first surface close to the electrode lead hole and the second surface.

[0020] When the internal pressure or temperature of the outer case reaches a threshold, the inclined first surface can induce deformation of the protrusion, making it easier for the protrusion to be pulled out of the electrode pull-out hole, and reducing pressure immediately, thereby improving the reliability of the battery cell.

[0021] In some embodiments, the electrode terminal includes a terminal body and a first stopper portion connected to each other, at least a portion of the terminal body is accommodated in the electrode lead-out hole, and the first stopper portion is located on a side of the wall portion facing the electrode assembly and protrudes from the outer circumferential surface of the terminal body. The first stopper portion includes a protrusion.

[0022] The terminal body is positioned so that it fits into the electrode lead-out hole, making it easier to connect the electrode terminal to other components outside the battery cell. The wall portion forms a barrier against the protrusion, thereby restricting the electrode terminal from detaching from the inside of the outer case.

[0023] In some embodiments, the first stop portion has a weakened portion along which the first stop portion can bend or break when the internal pressure or temperature of the outer case reaches a threshold value.

[0024] By installing a weak portion in the first stopper portion, when the internal pressure or temperature of the outer case reaches a threshold, the first stopper portion becomes less likely to deform, and can be bent or torn at a predetermined position, thereby connecting the internal space and external space of the outer case through the electrode pull-out hole and reducing the risk of the battery cell exploding.

[0025] In some embodiments, at least a portion of the projection of the weakened portion in the thickness direction of the wall portion is located within the electrode lead-out hole.

[0026] The above technical solution brings the curved portion of the first stopper portion closer to the electrode pull-out hole when the internal pressure or temperature of the outer case reaches a threshold, thereby making it easier to pull out the first stopper portion from the electrode pull-out hole.

[0027] In some embodiments, the first stopper portion includes a protrusion and a connecting portion, the connecting portion is used to connect the protrusion and the terminal body, and a projection of the connecting portion in the thickness direction of the wall portion is located between the outer peripheral surface of the terminal body and the hole wall of the electrode lead-out hole. The weakened portion is provided on the connecting portion.

[0028] When the internal pressure or temperature of the outer case reaches a threshold, the protrusion can be inverted as the weak portion bends, thereby releasing the wall portion and being pulled out from the electrode lead-out hole. By providing the weak portion at the connection portion, the restriction on the strength of the protrusion is relaxed, and the shape design of the protrusion becomes more flexible.

[0029] In some embodiments, a shallow groove is provided in the electrode terminal, and the weakened portion is formed at the bottom of the shallow groove. By forming the weakened portion by opening the shallow groove, the molding efficiency of the electrode terminal can be improved.

[0030] In some embodiments, the shallow groove is provided in a surface of the first stop portion facing the wall.

[0031] In some embodiments, the shallow groove is located on the surface of the first stop portion opposite the wall portion, and the shallow groove provides space for material to flow and helps to deflect the first stop portion when the internal pressure or temperature of the outer casing reaches a threshold.

[0032] In some embodiments, the electrode terminal has a recess that is recessed along the thickness direction of the wall from the inside of the outer case toward the outside of the outer case, and at least a portion of the recess is provided on the side of the terminal body facing the tab.

[0033] When the internal pressure or temperature of the outer case reaches a threshold value, the first stopper portion is bent, and the recess can provide space for material to flow as the first stopper portion is bent, thereby reducing the resistance of the first stopper portion to bending and allowing the first stopper portion to be immediately pulled out of the electrode pull-out hole.

[0034] In some embodiments, the recess includes a first side surface and a second side surface, the first side surface being arranged along the radial outside of the electrode lead-out hole of the second side surface, the first side surface being connected to the bottom surface of the recess surface, and being inclined toward a side away from the central axis of the electrode terminal.

[0035] By setting the first side at an angle, more space can be provided for the material to flow when the first stopper portion is bent, thereby reducing the resistance to bending of the first stopper portion.

[0036] In some embodiments, the recess includes a first side surface and a second side surface, the first side surface being arranged along the radial outside of the electrode lead-out hole of the second side surface, and the second side surface being connected to the bottom surface of the recess surface and being inclined toward the side closest to the central axis of the electrode terminal.

[0037] By setting the second side at an angle, the risk of interference between the second side and the first side is reduced when the first side is deformed due to the flow of material, and the resistance to bending of the first stopper portion is reduced.

[0038] In some embodiments, the first stopper portion is deflectable toward the recess when the internal pressure or temperature of the outer case reaches a threshold value.

[0039] When the internal pressure or temperature of the outer case reaches a threshold value, the first stopper portion bends toward the recess, causing the material to flow toward the recess, reducing the resistance of the first stopper portion to bending, and allowing the first stopper portion to be immediately pulled out of the electrode pull-out hole.

[0040] In some embodiments, the first stopper portion is formed by folding back a part of the electrode terminal.

[0041] During assembly, the electrode terminal can be inserted into the outer case through the electrode lead-out hole, and then a part of the electrode terminal is folded back to form a first stopper portion, thereby fixing the electrode terminal to the wall portion.

[0042] In some embodiments, the terminal body includes a terminal protrusion, and the recess is disposed around the terminal protrusion. In a thickness direction of the wall portion, an end face of the terminal protrusion facing the tab is closer to the tab than the first stopper portion.

[0043] The first stopper portion is less likely to interfere with the contact between the terminal protrusion and other components, thereby reducing excessive positioning and the risk of poor contact between the terminal protrusion and other components due to unevenness in the first stopper portion, improving the current-passing capacity and reliability of the battery cell.

[0044] In some embodiments, the electrode terminal further includes a second stopper portion that protrudes from the outer circumferential surface of the terminal body and is disposed outside the wall portion. At least a portion of the wall portion is located between the protrusion and the second stopper portion in the thickness direction of the wall portion. The wall portion is positioned between the first stopper portion and the second stopper portion, thereby limiting the relative movement between the electrode terminal and the wall portion.

[0045] In some embodiments, in the radial direction of the electrode lead-out hole, the end of the second stopper portion remote from the terminal body exceeds the end of the first stopper portion remote from the terminal body.

[0046] The second stopper portion has a larger diameter than the first stopper portion in the radial direction of the electrode lead-out hole, which increases the exposed area of ​​the electrode terminal, facilitating connection between the electrode terminal and an external bus member, increasing the connection area between the electrode terminal and the bus member, and improving current passing capacity. The first stopper portion has a larger diameter than the second stopper portion in the radial direction of the electrode lead-out hole, which makes it easier to deform and quickly reduce pressure when the internal pressure or temperature of the outer case reaches a threshold, improving the reliability of the battery cell.

[0047] In some embodiments, the first stopper portion, the second stopper portion, and the terminal body are integrally molded, which can improve the structural strength of the entire electrode terminal, reduce the internal resistance of the low-temperature electrode terminal, and improve the current-passing capacity.

[0048] In some embodiments, the battery cell further includes a sealing member, at least a portion of which is provided between the first stopper portion and the wall portion, and the sealing member can fill the gap between the first stopper portion and the wall portion, thereby sealing the electrode lead-out hole.

[0049] In some embodiments, the melting point of the electrode terminals is lower than that of the wall portion. When a short circuit, overcharging, or other phenomenon occurs, the temperature inside the outer case rises rapidly. The electrode terminals have a lower melting point than the wall portion, which allows the electrode terminals to melt or soften before the wall portion, thereby helping to achieve directional decompression of the battery cell.

[0050] In some embodiments, H2-H1≧300° C., where H1 is the melting point of the electrode terminal and H2 is the melting point of the wall portion.

[0051] When phenomena such as short circuits and overcharging occur, the internal temperature of the outer case becomes uneven. However, with the above technical solution, there is a large difference between the melting point of the electrode terminals and the melting point of the wall, which reduces the risk of the wall melting before the electrode terminals due to the uneven internal temperature, thereby improving the reliability of the battery cell.

[0052] In some embodiments, the material of the electrode terminal comprises aluminum or copper, and the material of the wall comprises steel.

[0053] By using steel as the main material for the wall, the wall has good mechanical strength and heat resistance, reducing the risk of the wall melting and exploding when the battery cell experiences thermal runaway.By using a material with a low melting point for the electrode terminals, the electrode terminals can soften and deform more easily when the battery cell experiences thermal runaway, allowing the internal and external spaces of the outer case to immediately communicate through the electrode outlet holes, reducing the risk of explosion and improving the reliability of the battery cell.

[0054] In some embodiments, the outer case includes a housing and an end cover, one end of the housing has an opening, the end cover covers the opening, the housing includes a side wall and an end wall, the side wall surrounds the outside of the electrode assembly, the end wall is positioned opposite the opening, and the wall is the end cover or the end wall.

[0055] The end covers or end walls are flatter than the side walls, and the electrode terminals are mounted on the end covers or end walls, thereby improving the assembly efficiency of the battery cell.

[0056] In some embodiments, the projection of the wall along its own thickness is rectangular or toroidal.

[0057] According to a second aspect, the present application provides a battery including a plurality of battery cells according to any of the embodiments of the first aspect.

[0058] According to a third aspect, the present application provides a power consumption device including a battery according to the second aspect for supplying electrical energy thereto. [Brief explanation of the drawings]

[0059] The features, advantages, and technical effects of exemplary embodiments of the present application are described below with reference to the drawings.

[0060] [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Figure 2] 1 is an exploded schematic view of a battery according to some embodiments of the present application. [Figure 3] FIG. 3 is a structural schematic diagram of the battery module shown in FIG. [Figure 4] 1 is a structural schematic diagram of a battery cell according to some embodiments of the present application; [Figure 5] FIG. 5 is a schematic cross-sectional view of the battery cell shown in FIG. [Figure 6] FIG. 6 is an enlarged schematic view of the circled area in FIG. 5. [Figure 7] 1 is a schematic cross-sectional view of a battery cell housing according to some embodiments of the present application. FIG. [Figure 8] 1 is a schematic cross-sectional view of an electrode terminal of a battery cell according to some embodiments of the present application. [Figure 9] 1 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 10] FIG. 10 is a schematic diagram of the electrode terminal shown in FIG. [Figure 11] FIG. 10 is a schematic cross-sectional view of an electrode terminal of a battery cell according to another embodiment of the present application. [Figure 12] 1 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 13] FIG. 13 is a schematic cross-sectional view of the electrode terminal shown in FIG. [Figure 14] FIG. 10 is a schematic cross-sectional view of an electrode terminal of a battery cell according to another embodiment of the present application. [Figure 15] FIG. 2 is a schematic cross-sectional view of a battery cell according to another embodiment of the present application. [Figure 16] FIG. 16 is a schematic cross-sectional view of the electrode terminal shown in FIG. [Figure 17]FIG. 2 is a schematic diagram of a three-dimensional structure of a battery cell according to another embodiment of the present application.

[0061] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION OF THE INVENTION

[0062] In order to clarify the objectives, technical solutions and advantages of the embodiments of the present application, the technical solutions in the embodiments of the present application will be described below clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments, and all other embodiments obtained by those skilled in the art based on the embodiments of the present application without any creative efforts fall within the scope of protection of the present application.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art, and the terms used in the specification of the application are merely for the purpose of describing specific embodiments and are not intended to limit the present application. The terms "comprises," "has," and any variations thereof in the specification and claims of the present application and the brief description of the drawings are intended to cover a non-exclusive "comprise." The terms "first," "second," etc. in the specification and claims of the present application or the drawings are not intended to describe a specific order or a hierarchical relationship, but are intended to distinguish between different objects.

[0064] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. Appearances of the term "embodiment" in various places in this specification do not necessarily refer to the same embodiment, nor do they refer to embodiments that are mutually exclusive, independent, or alternative to other embodiments.

[0065] It should be explained in the description of this application that, unless otherwise clearly specified and limited, the terms "attach," "connected," "connection," and "attachment" should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection. They may be directly connected, indirectly connected via an intermediate medium, or internal communication between two elements. Those skilled in the art can understand the specific meanings of the above terms in this application according to specific circumstances.

[0066] The term "and / or" in this application merely describes the relationship between related objects and indicates that three relationships may exist. For example, A and / or B may represent three cases: A alone, a combination of A and B, and B alone. In addition, the character " / " in this application generally indicates that the related objects before and after it are in an "or" relationship.

[0067] In the embodiments of the present application, the same reference numerals represent the same elements, and for the sake of brevity, detailed descriptions of the same elements will be omitted in different embodiments. It should be understood that the dimensions such as thickness, length, width, etc. of various elements in the embodiments of the present application shown in the drawings, and the overall dimensions such as thickness, length, width, etc. of the integrated device are for illustrative purposes only and should not be construed as any limitation on the present application.

[0068] The term "plurality" as used herein refers to two or more (including two).

[0069] In the present embodiment, the battery cell may be a secondary battery, which refers to a battery cell that can be continuously used after being discharged by being charged to activate the active material.

[0070] The battery cells may be lithium ion batteries, sodium ion batteries, sodium lithium ion batteries, lithium metal batteries, sodium metal batteries, lithium sulfur batteries, magnesium ion batteries, nickel metal hydride batteries, nickel cadmium batteries, lead acid batteries, etc., and the embodiments of the present application are not limited thereto.

[0071] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (e.g., lithium ions) shuttle between the positive electrode and the negative electrode, intercalating and deintercalating. The separator, located between the positive electrode and the negative electrode, prevents short-circuiting between the positive and negative electrodes and allows the active ions to pass through.

[0072] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0073] As an example, the positive electrode current collector has two surfaces that are opposite to each other in the thickness direction of the positive electrode current collector, and the positive electrode active material is disposed on either or both of the two surfaces that are opposite to each other of the positive electrode current collector.

[0074] As an example, the positive electrode current collector may be a metal foil sheet or a composite current collector. For example, the metal foil sheet may be made of silver-surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, graphite, carbon, nickel, or titanium. The composite current collector may include a polymer substrate layer and a metal layer. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) on a polymer substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, or polyethylene).

[0075] For example, the positive electrode active material may include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound 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 may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates include, but are not limited to, at least one of lithium iron phosphate (e.g., LiFePO4 (also known as LFP)), a lithium iron phosphate and carbon composite, lithium manganese phosphate (e.g., LiMnPO4), a lithium manganese phosphate and carbon composite, lithium manganese iron phosphate, and a lithium manganese iron phosphate and carbon composite. Examples of lithium transition metal oxides include lithium cobalt oxide (LiCoO2, etc.), lithium nickel oxide (LiNiO2, etc.), lithium manganese oxide (LiMnO2, LiMn2O4, etc.), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM 333 (also called LiNi) 0.5 Co 0.2 Mn 0.3 O2(NCM 523 (also called LiNi) 0.5 Co 0.25 Mn 0.25 O2(NCM 211 (also called LiNi) 0.6 Co 0.2 Mn 0.2 O2(NCM 622 (also called LiNi) 0.8 Co 0.1 Mn 0.1 O2(NCM 811 Lithium Nickel Cobalt Aluminum Oxide (LiNi 0.80 Co 0.15 Al 0.05 O2) and / or modifying compounds thereof.

[0076] In some embodiments, the positive electrode may be a metal foam. The metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. When the metal foam is used as the positive electrode, a positive electrode active material may or may not be provided on the surface of the metal foam. For example, a lithium source material, such as potassium metal or sodium metal, may be filled and / or deposited in the metal foam, and the lithium source material may be lithium metal and / or a lithium-rich material.

[0077] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0078] For example, the negative electrode current collector can be a metal foil, a metal foam, or a composite current collector. For example, the metal foil can be silver-surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer substrate layer and a metal layer. The composite current collector can be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) on a polymer substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, or polyethylene).

[0079] For example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0080] As an example, the negative electrode current collector has two surfaces facing each other in the thickness direction thereof, and the negative electrode active material is provided on one or both of the two facing surfaces of the negative electrode current collector.

[0081] For example, the negative electrode active material may be a negative electrode active material for battery cells known in the art. For example, the negative electrode active material may include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of silicon elemental, silicon oxide, silicon carbon composite, silicon nitrogen composite, and silicon alloy. The tin-based material may be selected from at least one of tin elemental, tin oxide, and tin alloy. However, the present application is not limited to these materials, and other conventional materials usable as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination.

[0082] In some embodiments, the positive current collector material may be aluminum and the negative current collector material may be copper.

[0083] In some embodiments, the electrode assembly further includes a separator member disposed between the positive electrode and the negative electrode.

[0084] In some embodiments, the isolating member is a separator. The present application does not particularly limit the type of separator, and any separator with a well-known porous structure having good chemical and mechanical stability may be selected.

[0085] For example, the main material of the separator may be selected from at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator may be a single-layer thin film or a multi-layer composite thin film, without any particular limitations. When the separator is a multi-layer composite thin film, the materials of each layer may be the same or different, without any particular limitations. The separator may be located between the positive and negative electrodes as a separate component, or may be attached to the surfaces of the positive and negative electrodes.

[0086] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive and negative electrodes and simultaneously serves to transfer ions and separate the positive and negative electrodes.

[0087] In some embodiments, the battery cell further includes an electrolyte, which serves to conduct ions between the positive electrode and the negative electrode. The present application does not particularly limit the type of electrolyte, and it can be selected as needed. The electrolyte may be liquid, gel-like, or solid.

[0088] Here, the liquid electrolyte includes an electrolyte salt and a solvent.

[0089] In some embodiments, the electrolyte salt may be chosen from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluorobis(oxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0090] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, ethyl methyl sulfone, and diethyl sulfone. The solvent may optionally be an ether-based solvent. The ether-based solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

[0091] Here, the gel electrolyte comprises a polymer-based electrolyte skeletal network combined with an ionic liquid-lithium salt.

[0092] Here, the solid electrolyte includes polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0093] By way of example, the polymer solid electrolyte may be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single ionic polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0094] By way of example, the inorganic solid electrolyte may be one or more of oxide solid electrolytes (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superionic conductors (lithium germanium phosphate sulfur, sulfur silver germanite), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0095] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler in a polymer solid electrolyte.

[0096] In some embodiments, the electrode assembly is a wound structure, where the positive electrode sheet and the negative electrode sheet are wound to form the wound structure.

[0097] In some embodiments, the electrode assembly is a laminate structure.

[0098] For example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0099] For example, multiple positive electrode sheets may be installed, and the negative electrode plate may be folded to form multiple folded segments that are stacked and installed, with one positive electrode sheet sandwiched between adjacent folded segments.

[0100] By way of example, both the positive electrode sheet and the negative electrode plate are folded to form a plurality of folded segments that are placed in a stack.

[0101] For example, a plurality of separators may be provided, each of which may be provided between any adjacent positive electrode sheets or negative electrode plates.

[0102] As an example, the separator may be disposed continuously and placed between any adjacent positive or negative electrode sheets in a folded or wound manner.

[0103] In some embodiments, the electrode assembly may have a cylindrical, flat, or polygonal prism shape, or the like.

[0104] In some embodiments, the electrode assembly is provided with tabs that allow electrical current to be conducted away from the electrode assembly, including positive and negative tabs.

[0105] In some embodiments, the battery cell may include an outer case for packaging components such as the electrode assembly and the electrolyte. The outer case may be a steel case, an aluminum case, a plastic case (e.g., polypropylene), a composite metal case (e.g., a copper-aluminum composite outer case), an aluminum-plastic film, or the like.

[0106] For example, the battery cells may be cylindrical battery cells, prismatic battery cells, soft-pack battery cells, or other shaped battery cells, where prismatic battery cells include rectangular battery cells, blade-shaped battery cells, and polygonal prismatic batteries, and polygonal prismatic batteries include hexagonal prismatic batteries, etc., and the present application is not particularly limited thereto.

[0107] A battery as referred to in the examples of this application refers to a single physical module containing one or more battery cells to provide higher voltage and capacity.

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

[0109] In some embodiments, the battery may be a battery pack, which includes a housing and battery cells, and the battery cells or modules are housed in the housing.

[0110] In some embodiments, the housing may be part of a chassis structure of a vehicle, for example, a portion of the housing may form at least a portion of the floor of the vehicle, or a portion of the housing may form at least a portion of the cross beams and longitudinal beams of the vehicle.

[0111] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, or the like.

[0112] In some embodiments, a battery cell generally includes an electrode assembly, electrode terminals, and an outer case. The electrode assembly is electrically connected to the outside via the electrode terminals. The outer case can accommodate the electrode assembly and provide support for the electrode assembly.

[0113] If a short circuit, overcharging, or other such phenomenon occurs, thermal runaway will occur inside the battery cell, causing the internal pressure of the outer case to rise suddenly, creating the risk of the battery cell exploding.

[0114] In view of the above, the embodiments of the present application provide a battery cell that, when the internal pressure or temperature of the outer case reaches a threshold, utilizes deformation of the electrode terminals to connect the internal space of the outer case with the external space, thereby releasing the internal pressure of the battery cell and reducing the risk of the battery cell exploding. Compared with a solution that requires an additional pressure reducing mechanism to be installed in the outer case, the present application can simplify the structure of the battery cell.

[0115] The battery cells described in the embodiments of the present application are applied to batteries and power consuming devices that use batteries.

[0116] The battery cells, batteries, and power consumption devices disclosed in the embodiments of the present application can be used in various energy storage systems that use batteries as power sources or batteries as energy storage elements. The power consumption devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery cars, electric vehicles, boats, spacecraft, etc. The electric toys may include stationary or mobile electric toys such as game consoles, electric car toys, electric boat toys, and electric aircraft toys, and the spacecraft may include aircraft, rockets, space shuttles, spaceships, etc.

[0117] For convenience of explanation, the following embodiment will be described using a vehicle as an example of a power consuming device.

[0118] FIG. 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application.

[0119] 1, a battery 2 is installed inside the vehicle 1, and the battery 2 may be installed at the bottom, front, or rear of the vehicle 1. The battery 2 can be used to supply power to the vehicle 1, and can be used, for example, as an operating power source for the vehicle 1.

[0120] The vehicle 1 may further include a controller 3 and a motor 4, where the controller 3 is used to control the battery 2 to supply power to the motor 4, for example, to meet the operating power needs of the vehicle 1 for starting, navigation, and driving.

[0121] In some embodiments of the present application, the battery 2 can provide driving power to the vehicle 1 not only as an operating power source for the vehicle 1 but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas.

[0122] 2 is an exploded schematic view of a battery according to some embodiments of the present application. As shown in FIG. 2, the battery 2 includes a housing 5 and a battery cell (not shown in FIG. 2), and the battery cell is housed in the housing 5.

[0123] The housing 5 is used to house the battery cells and may have various structures. In some embodiments, the housing 5 may include a first housing portion 5a and a second housing portion 5b, which are fitted over each other, and together define a housing space 5c for housing the battery cells. The second housing portion 5b may have a hollow structure with one end open, and the first housing portion 5a may have a plate-like structure, and the first housing portion 5a is fitted over the open side of the second housing portion 5b, thereby forming the housing 5 having the housing space 5c. Both the first housing portion 5a and the second housing portion 5b may have a hollow structure with one end open, and the open side of the first housing portion 5a is fitted over the open side of the second housing portion 5b, thereby forming the housing 5 having the housing space 5c. The first housing portion 5a and the second housing portion 5b may have various shapes, such as a cylinder or a rectangular parallelepiped.

[0124] In order to improve the sealing performance after the first housing part 5a and the second housing part 5b are connected, a sealing member such as a sealant or a seal ring may be installed between the first housing part 5a and the second housing part 5b.

[0125] When the first housing part 5a is placed over the top of the second housing part 5b, the first housing part 5a can be called an upper housing cover, and the second housing part 5b can be called a lower housing.

[0126] The battery 2 may have one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, parallel, or series-parallel, and a series-parallel connection refers to not only a series connection but also a parallel connection of the multiple battery cells. The multiple battery cells can be directly connected in series, parallel, or series-parallel, and then the entire configuration of the multiple battery cells can be housed in the housing 5. Of course, multiple battery cells can first be connected in series, parallel, or series-parallel to form a battery module 6, and then the multiple battery modules 6 can be further connected in series, parallel, or series-parallel to form an integrated battery module and housed in the housing 5.

[0127] A battery cell may be the smallest unit that constitutes a battery.

[0128] FIG. 3 is a structural schematic diagram of the battery module shown in FIG.

[0129] 3, there are a plurality of battery cells 7, and the plurality of battery cells 7 are first connected in series, in parallel, or in series-parallel to form a battery module 6. A plurality of battery modules 6 may be further connected in series, in parallel, or in series-parallel to form an integrated unit housed in a housing.

[0130] The plurality of battery cells 7 in the battery module 6 may be electrically connected by a bus member, thereby realizing a series connection, a parallel connection, or a series-parallel connection of the plurality of battery cells 7 in the battery module 6. There may be one or more bus members, and each bus member is used to electrically connect at least two battery cells.

[0131] FIG. 4 is a structural schematic diagram of a battery cell according to some embodiments of the present application, FIG. 5 is a cross-sectional schematic diagram of the battery cell shown in FIG. 4, FIG. 6 is an enlarged schematic diagram of the circled area in FIG. 5, FIG. 7 is a local cross-sectional schematic diagram of a housing of a battery cell according to some embodiments of the present application, and FIG. 8 is a cross-sectional schematic diagram of an electrode terminal of a battery cell according to some embodiments of the present application.

[0132] As shown in FIGS. 4 to 8 , an embodiment of the present application provides a battery cell 7 including an outer case 20, an electrode assembly 10, and other functional components (e.g., an electrode terminal 30 installed in the outer case 20), and at least a portion of the electrode assembly 10 is housed within the outer case 20.

[0133] The outer case 20 has a hollow structure, and an accommodating space for accommodating the electrode assembly 10 and the electrolyte is formed inside. The shape of the outer case 20 is determined depending on the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 has a rectangular parallelepiped structure, a rectangular parallelepiped outer case can be selected, and if the electrode assembly 10 has a cylindrical structure, a cylindrical outer case can be selected.

[0134] As an example, the outer case 20 includes a housing 21 and an end cover 22, the housing 21 having an opening, and the end cover 22 covering the opening.

[0135] The housing 21 is an assembly that mates with the end cover 22 to form an internal cavity of the battery cell 7, and the formed internal cavity can be used to accommodate the electrode assembly 10, electrolyte, and other components.

[0136] The housing 21 and the end cover 22 may be separate members. For example, an opening may be provided in the housing 21, and the end cover 22 may be placed over the opening at the opening, thereby forming an internal cavity for the battery cell 7.

[0137] The housing 21 may have various shapes and sizes, such as a rectangular parallelepiped, a cylinder, a hexagonal prism, etc. The specific shape of the housing 21 is determined depending on the specific shape and size of the electrode assembly 10. The housing 21 may be made of any of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc., and the embodiments of the present application are not particularly limited thereto.

[0138] The shape of the end cover 22 can be adapted to the shape of the housing 21 to fit with the housing 21. The material of the end cover 22 may be the same as or different from the material of the housing 21. Preferably, the end cover 22 is made of a material with a certain hardness and strength (e.g., copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.), which makes the end cover 22 less likely to deform when pressed or hit, and allows the battery cells 7 to have higher structural strength and improved reliability.

[0139] The end cover 22 is connected to the housing 21 by welding, adhesive, fastening, or other methods.

[0140] The housing 21 may be open on one end or on both ends. In some examples, the housing 21 may be open on one end, and one end cover 22 is installed and placed over the housing 21. In other examples, the housing 21 may be open on both ends, and two end covers 22 are installed, and the two end covers 22 are placed over the two openings of the housing 21, respectively.

[0141] The electrode terminal 30 can be used to electrically connect with the electrode assembly 10 and is used to output or input electrical energy to the battery cell 7 .

[0142] The electrode assembly 10 is a component that causes an electrochemical reaction in the battery cell 7. One or more electrode assemblies 10 can be contained within the housing 21.

[0143] For example, the electrode assembly 10 includes a positive electrode sheet and a negative electrode sheet. The portions of the positive electrode sheet and the negative electrode sheet containing the active material constitute the main body of the electrode assembly 10, and the portions of the positive electrode sheet and the negative electrode sheet not containing the active material constitute tabs, respectively. The tabs may include a positive electrode tab and a negative electrode tab. The positive electrode tab and the negative electrode tab may both be located at one end of the main body, or may be located at both ends of the main body.

[0144] During the charging and discharging process of the battery, the positive and negative active materials react with the electrolyte, and the tabs are connected to the electrode terminals 30 to form a current circuit.

[0145] In some embodiments, the battery cell 7 includes an outer case 20, an electrode assembly 10, and an electrode terminal 30. The outer case 20 includes a wall 23, and an electrode lead-out hole 231 is provided in the wall 23. At least a portion of the electrode assembly 10 is housed within the outer case 20, and the electrode assembly 10 includes a tab 11. The electrode terminal 30 is installed on the wall 23 and covers at least a portion of the electrode lead-out hole 231, and the electrode terminal 30 is electrically connected to the tab 11. At least a portion of the electrode terminal 30 is deformable when the internal pressure or temperature of the outer case 20 reaches a threshold, thereby communicating the interior and exterior spaces of the outer case 20 through the electrode lead-out hole 231 and discharging gas within the outer case 20.

[0146] As an example, the wall 23 may be the end cover 22 or one wall of the housing 21 .

[0147] By way of example, the shape of the wall 23 may be circular, rectangular, oval or other shape.

[0148] For example, the electrode lead-out hole 231 penetrates the wall portion 23, thereby allowing the electrode terminal 30 to easily extract the electrical energy of the electrode assembly 10 to the outside of the outer case 20. Optionally, the electrode lead-out hole 231 penetrates the wall portion 23 along the thickness direction Z of the wall portion 23.

[0149] The tab 11 electrically connected to the electrode terminal 30 may be a positive electrode tab or a negative electrode tab.

[0150] The tab 11 may be directly connected to the electrode terminal 30, for example, by welding, abutting, or other methods. Alternatively, the tab 11 may be indirectly connected to the electrode terminal 30 via another conductive member (for example, a current collecting member 40), thereby realizing electrical connection between the tab 11 and the electrode terminal 30.

[0151] The material of the electrode terminal 30 may be the same as or different from the material of the wall portion 23. For example, different materials may be used for the electrode terminal 30 and the wall portion 23, and the melting point of the electrode terminal 30 may be the same as or different from the melting point of the wall portion 23.

[0152] The electrode terminal 30 may cover only a portion of the electrode lead-out hole 231, or may completely cover the electrode lead-out hole 231. For example, the electrode terminal 30 may seal the electrode lead-out hole 231 by itself, isolating the interior space of the outer case 20 from the exterior space and improving the sealing performance of the battery cell 7; alternatively, the electrode terminal 30 may be combined with another functional member (e.g., a sealing member 50) to jointly seal the electrode lead-out hole 231, isolating the interior space of the outer case 20 from the exterior space and improving the sealing performance of the battery cell 7.

[0153] The design of the threshold value varies depending on the design requirements, and may depend on one or more materials of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 7.

[0154] When the internal pressure or temperature of the outer case 20 reaches a threshold, the deformation of the electrode terminal 30 includes, but is not limited to, bending, bursting, shrinking, melting, and the like.

[0155] When a short circuit, overcharge, or other phenomenon occurs, the electrolyte and active material react to release gas and heat.

[0156] In the embodiments of the present application, the deformation of the electrode terminal 30 may be triggered only by the internal pressure of the outer case 20, only by the internal temperature of the outer case 20, or even by a combination of the internal pressure and the internal temperature of the outer case 20.

[0157] For example, as gas continuously accumulates in the outer case 20, the internal pressure of the outer case 20 will reach and even exceed a pressure threshold. When the internal pressure of the outer case 20 reaches the threshold, the electrode terminal 30 will deform under the action of the internal pressure, thereby connecting the internal space of the outer case 20 with the external space through the electrode lead-out hole 231, and the gas inside the outer case 20 will be discharged through the electrode lead-out hole 231, reducing the risk of the battery cell 7 exploding.

[0158] For example, when the electrolyte reacts with the active material and heat is rapidly released, the internal temperature of the outer case 20 rises, and the temperature increase also causes an increase in the internal pressure of the outer case 20. When the internal temperature of the outer case 20 reaches a threshold, the electrode terminal 30 deforms under the action of the temperature and pressure, thereby connecting the internal space of the outer case 20 with the external space through the electrode lead-out hole 231, and the gas inside the outer case 20 is discharged through the electrode lead-out hole 231, reducing the risk of the battery cell 7 exploding.

[0159] When the internal pressure or temperature of the outer case 20 reaches a threshold, the embodiment of the present application utilizes deformation of the electrode terminals 30 to connect the internal space of the outer case 20 with the external space, thereby releasing the internal gas and pressure of the outer case 20 and reducing the risk of explosion of the battery cell 7. Compared with a method in which an additional pressure reducing mechanism is installed in the outer case 20, the embodiment of the present application can simplify the structure of the battery cell 7 and reduce the cost of the battery cell.

[0160] In some embodiments, at least a portion of the electrode terminal 30 can detach from the wall 23 when the internal pressure or temperature of the outer case 20 reaches a threshold value.

[0161] When the internal pressure or temperature of the outer case 20 reaches a threshold value, the electrode terminal 30 may be entirely or partially detached from the wall portion 23 .

[0162] The phrase "at least a part of the electrode terminal 30 is detached from the wall portion 23" means that at least a part of the electrode terminal 30 is not constrained by the wall portion 23 and may be displaced from the initial set position.

[0163] When at least a portion of the electrode terminal 30 is detached from the wall portion 23, at least a portion of the electrode lead-out hole 231 is no longer covered by the electrode terminal 30, and the electrode lead-out hole 231 can communicate between the internal space of the outer case 20 and the external space, thereby releasing the internal gas of the battery cell 7 and reducing the internal pressure and temperature of the battery cell 7.

[0164] In some embodiments, the electrode terminal 30 can entirely detach from the wall 23 when the internal pressure or temperature of the outer case 20 reaches a threshold value.

[0165] If a phenomenon such as a short circuit or overcharging occurs, the electrode terminal 30 can be detached from the wall portion 23, so that the electrode lead-out hole 231 is no longer blocked by the electrode terminal 30, increasing the rate at which gas is released and reducing the risk of the battery cell 7 exploding.

[0166] In some embodiments, the outer case 20 includes a housing 21 and an end cover 22. One end of the housing 21 has an opening, and the end cover 22 covers the opening. The housing 21 includes a side wall 212 and an end wall 211. The side wall 212 surrounds the outside of the electrode assembly 10, and the end wall 211 is located opposite the opening. The wall 23 is the end cover 22 or the end wall 211.

[0167] The side wall 212 may be one or more. In some examples, the side wall 212 may be one and may have a cylindrical structure. In other examples, the side wall 212 may be multiple and connected in sequence along the circumferential direction of the electrode assembly 10, for example, four side walls 212, and the four side walls 212 are connected in sequence to form a prismatic structure.

[0168] In some embodiments, the battery cell 7 is a cylindrical battery cell, and has a single side wall 212 and a cylindrical structure. The end cover 22 or the end wall 211 is flatter than the side wall 212, and the electrode terminals 30 are mounted on the end cover 22 or the end wall 211, which can improve the assembly efficiency of the battery cell 7.

[0169] In some embodiments, housing 21 is a one-piece structure and wall 23 is an end wall 211 .

[0170] In some embodiments, the melting point of electrode terminal 30 is lower than the melting point of wall portion 23 .

[0171] When a phenomenon such as a short circuit or overcharging occurs, the temperature inside the outer case 20 rises rapidly. The electrode terminals 30 have a lower melting point than the wall portions 23, which allows the electrode terminals 30 to melt or soften before the wall portions 23 do, which helps to achieve directional decompression of the battery cells 7.

[0172] Furthermore, when connecting the electrode terminal 30 to other components by welding, the low melting point of the material of the electrode terminal 30 is advantageous in reducing the welding temperature, and the relatively high melting point of the material of the wall 23 can reduce the adverse effects of the welding process on the wall 23, thereby reducing the risk of electrolyte leakage.

[0173] In some embodiments, when the melting point of the electrode terminal 30 is H1 and the melting point of the wall portion 23 is H2, H2-H1≧300°C.

[0174] When a phenomenon such as a short circuit or overcharging occurs, the internal temperature of the outer case 20 becomes uneven. However, according to the embodiment of the present application, there is a large difference between the melting point of the electrode terminal 30 and the melting point of the wall portion 23, so the risk of the wall portion 23 melting before the electrode terminal 30 due to the uneven internal temperature can be reduced, improving the reliability of the battery cell 7.

[0175] Optionally, H2-H1≧500°C.

[0176] In some embodiments, the material of the electrode terminal 30 includes aluminum or copper, and the material of the wall 23 includes steel. As an example, the material of the wall 23 may be stainless steel, nickel-plated steel, or other steel-based materials.

[0177] By using steel as the main material for the wall 23, the wall 23 has good mechanical strength and heat resistance, reducing the risk of the wall 23 melting and exploding in the event of thermal runaway in the battery cell 7. The electrode terminal 30 is made of a material with a low melting point, which makes it easier for the electrode terminal 30 to soften and deform in the event of thermal runaway in the battery cell 7, thereby allowing the internal and external spaces of the outer case 20 to communicate immediately via the electrode lead-out holes 231, reducing the risk of explosion and improving the reliability of the battery cell 7.

[0178] In some embodiments, the battery cell 7 further includes a current collecting member 40, which is connected to the electrode terminal 30 and the tab 11. Optionally, when the internal pressure or temperature of the outer case 20 reaches a threshold, the electrode terminal 30 is disconnected from the current collecting member 40 and detached from the wall 23.

[0179] In some embodiments, the current collecting member 40 may be connected to the tab 11 by welding, abutting, adhesive, or other methods, and is connected to the electrode terminal 30 by welding, abutting, adhesive, or other methods, thereby achieving an electrical connection between the electrode terminal 30 and the tab 11.

[0180] The current collecting member 40 is made of a conductive material, for example, the current collecting member 40 is made of a conductive metal.

[0181] In some embodiments, the surface of the current collecting member 40 opposite the wall 23 abuts against the tab 11 , and the surface of the current collecting member 40 facing the wall 23 abuts against the electrode terminal 30 .

[0182] In some embodiments, current collecting member 40 is welded to tab 11. By way of example, current collecting member 40 is connected to tab 11 by ultrasonic welding, laser welding, or other welding methods.

[0183] In some embodiments, the primary material of the current collecting member 40 is the same as the primary material of the tab 11 .

[0184] In some examples, the main material of the current collecting member 40 is aluminum, and the main material of the tab 11 is aluminum. For example, the main material of the current collecting member 40 is aluminum alloy, and the main material of the tab 11 is aluminum foil.

[0185] In another example, the main material of the current collecting member 40 is copper, and the main material of the tab 11 is copper. For example, the main material of the current collecting member 40 is a copper alloy, and the main material of the tab 11 is copper foil. The main material of the current collecting member 40 is the same as the main material of the tab 11, which can improve the welding strength between the current collecting member 40 and the tab 11, reduce resistance, and improve current passing capacity.

[0186] In some embodiments, the current collecting member 40 is welded to the electrode terminal 30. By way of example, the current collecting member 40 is connected to the electrode terminal 30 by laser welding, resistance welding, ultrasonic welding, or other welding methods.

[0187] In some embodiments, the main material of the current collecting member 40 is the same as the main material of the electrode terminal 30 .

[0188] In some examples, the main material of the current collecting member 40 is aluminum, and the main material of the electrode terminal 30 is aluminum. For example, the materials of both the electrode terminal 30 and the current collecting member 40 are aluminum alloys.

[0189] In another example, the main material of the current collecting member 40 is copper, and the main material of the electrode terminal 30 is copper. For example, the materials of both the electrode terminal 30 and the current collecting member 40 are copper alloys.

[0190] In some embodiments, when the internal temperature of the outer case 20 reaches a threshold value, the strength of the weld between the electrode terminal 30 and the current collecting member 40 decreases, and under the action of the internal pressure of the outer case 20, the electrode terminal 30 and the current collecting member 40 are torn apart, and the electrode terminal 30 is released from the constraint of the current collecting member 40, allowing the electrode terminal 30 to detach from the wall portion 23.

[0191] In some embodiments, if the internal pressure or temperature of the outer case 20 reaches a threshold, the weld between the electrode terminal 30 and the current collecting member 40 will tear, but the weld between the tab 11 and the current collecting member 40 will maintain a fixed connection between the tab 11 and the current collecting member 40, thereby reducing the risk of the current collecting member 40 clogging the electrode lead-out hole 231.

[0192] In some embodiments, the electrode terminal 30 includes a protrusion 311 that protrudes from the hole wall 231a of the electrode lead-out hole 231 along the radial direction of the electrode lead-out hole 231, and the protrusion 311 is located on the side of the wall 23 facing the electrode assembly 10.

[0193] The radial direction of the electrode lead-out hole 231 may be a direction that passes through the central axis X of the electrode lead-out hole 231 and is perpendicular to the central axis X of the electrode lead-out hole 231. Optionally, the central axis X of the electrode lead-out hole 231 is parallel to the thickness direction Z of the wall portion 23.

[0194] The central axis X of the electrode lead-out hole 231 is an imaginary line. As an example, the electrode lead-out hole 231 is rotationally symmetrical with respect to the central axis.

[0195] In some examples, the electrode lead-out hole 231 may be a circular hole, and the radial direction of the electrode lead-out hole 231 may be the radial direction of the electrode lead-out hole 231. In other examples, the electrode lead-out hole 231 may be a rectangular hole, and the radial direction of the electrode lead-out hole 231 may be the radial direction of the circumscribing circle of the electrode lead-out hole 231.

[0196] The protrusion 311 protruding from the hole wall 231 a of the electrode lead-out hole 231 may mean that the projection of the protrusion 311 does not overlap the projection of the electrode lead-out hole 231 in the thickness direction Z of the wall portion 23 .

[0197] There may be one or more protrusions 311. In some examples, there is one protrusion 311 and it is ring-shaped, and in other examples, there are multiple protrusions 311, and the multiple protrusions 311 are installed at intervals along the circumferential direction of the electrode lead-out hole 231.

[0198] While the battery cell 7 is operating normally, the wall portion 23 can stop the protrusion 311 , thereby reducing the risk of the electrode terminal 30 coming out of the electrode lead-out hole 231 .

[0199] In some embodiments, the protrusions 311 are deformable when the internal pressure or temperature of the outer case 20 reaches a threshold value.

[0200] Deformation of the protrusion 311 includes, but is not limited to, tearing, bending, melting, and the like.

[0201] When the internal pressure or temperature of the outer case 20 reaches a threshold, the protrusion 311 is deformable, so that the wall 23 no longer blocks the protrusion 311, the electrode terminal 30 escapes from the electrode pull-out hole 231, the internal space of the outer case 20 communicates with the external space through the electrode pull-out hole 231, and the gas inside the outer case 20 is discharged through the electrode pull-out hole 231, reducing the risk of the battery cell 7 exploding.

[0202] For example, when the internal pressure or temperature of the outer case 20 reaches a threshold value, the electrode terminal 30 moves outward from the electrode pull-out hole 231 due to the action of the internal pressure, and in the process of the electrode terminal 30 moving, the protrusion 311 is folded back and deformed under the action of the resistance force of the wall portion 23, thereby allowing the protrusion 311 to be pulled out from the electrode pull-out hole 231.

[0203] In some embodiments, the maximum dimension by which the protrusion 311 protrudes from the hole wall 231a of the electrode lead hole 231 is L1, and the minimum distance between the periphery 23a of the wall 23 and the hole wall 231a of the electrode lead hole 231 is L2. L1 and L2 satisfy 0.1≦L1 / L2≦0.5.

[0204] As an example, L1 may be the maximum dimension by which the protrusion 311 protrudes from the hole wall 231a of the electrode hole 231 in the radial direction of the electrode hole 231. As an example, L2 may be the minimum distance between the periphery 23a of the wall 23 and the hole wall 231a of the electrode hole 231 in the radial direction of the electrode hole 231.

[0205] For example, when the wall portion 23 is the end cover 22, the peripheral edge 23a of the wall portion 23 may be the outer periphery of the end cover 22. When the wall portion 23 is the end wall 211, the peripheral edge 23a of the wall portion 23 may be the connection point between the end wall 211 and the side wall 212.

[0206] There is a positive correlation between the value of L1 / L2 and the area of ​​the protrusion 311 blocked by the wall 23. The larger the L1 / L2 ratio, the more difficult it is for the protrusion 311 to deform under the action of internal pressure, and the smaller the L1 / L2 ratio, the less stable the electrode terminal 30 is on the wall 23.

[0207] In the present embodiment, by limiting the value of L1 / L2 to 0.5 or less, the outer case 20 can deform immediately when the internal pressure or temperature reaches a threshold, improving the reliability of the battery cell 7. In the present embodiment, by limiting the value of L1 / L2 to 0.1 or more, the stability of the electrode terminal 30 on the wall 23 can be improved, reducing the risk of the electrode terminal 30 falling off when the battery cell 7 is subjected to an external impact.

[0208] Optionally, the value of L1 / L2 is 0.1, 0.2, 0.3, 0.4 or 0.5.

[0209] Optionally, the value of L1 / L2 is between 0.2 and 0.3.

[0210] In some embodiments, the maximum dimension of the protrusion 311 protruding from the hole wall 231a of the electrode lead-out hole 231 is L1, and the maximum thickness of the protrusion 311 is T1. L1 and T1 are 0.25 mm 2 ≦L1×T1≦25mm 2 Meet the following.

[0211] Both L1 and T1 affect the degree of difficulty in deforming the protrusion 311. The larger L1, the stronger the protrusion 311 and the greater the degree of difficulty in deforming the protrusion 311. Similarly, the larger T1, the stronger the protrusion 311 and the greater the degree of difficulty in deforming the protrusion 311.

[0212] In the present embodiment, the value of L1 × T1 is set to 25 mm. 2 By limiting the value of L1×T1 to 0.25 mm or less, the outer case 20 can be deformed immediately when the internal pressure or temperature reaches a threshold, improving the reliability of the battery cell 7. 2 By limiting the above, the stability of the electrode terminal 30 on the wall portion 23 can be improved, and the risk of the electrode terminal 30 falling off when the battery cell 7 receives an external impact can be reduced.

[0213] Alternatively, the value of L1 x T1 is 0.25 mm 2 , 0.5mm 2 , 1mm 2 , 5mm 2 , 8mm 2 , 10mm 2 , 15mm 2 , 20mm 2 or 25mm 2 is.

[0214] Alternatively, the value of L1 x T1 is 1 mm 2 ≦L1×T1≦5mm 2 is.

[0215] In some embodiments, T1 is between 0.5 mm and 5 mm. As an example, T1 is 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, or 5 mm.

[0216] In the present embodiment, by limiting T1 to 0.5 mm to 5 mm, the outer case 20 can deform immediately when the internal pressure or temperature reaches a threshold, and the risk of the electrode terminal 30 falling off when the battery cell 7 is subjected to an external impact is reduced.

[0217] In some embodiments, L1 is between 0.5 mm and 5 mm. As an example, L1 is 0.5 mm, 0.8 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, or 5 mm.

[0218] In some embodiments, the thickness of at least a part of the protrusion 311 gradually decreases in the direction from the central axis X of the electrode lead-out hole 231 toward the outer circumferential edge 311 a of the protrusion 311 .

[0219] The protrusion 311 includes a thickness change region in which the thickness gradually decreases, and the thickness of the thickness change region is greatest at one end close to the central axis X of the electrode lead-out hole 231, and the thickness of the thickness change region is smallest at one end close to the outer peripheral edge 311a of the protrusion 311.

[0220] In the present invention, by providing a thickness change region in which the thickness gradually decreases in the protrusion 311, the protrusion 311 becomes more easily deformed under the action of internal pressure, thereby quickly reducing pressure and improving the reliability of the battery cell 7.

[0221] In some embodiments, the protrusion 311 has a first surface 311b facing the wall 23, the wall 23 has a second surface 232 facing the protrusion 311, the second surface 232 being perpendicular to the thickness direction Z of the wall 23, and the first surface 311b being inclined relative to the second surface 232 in a direction closer to the electrode assembly 10.

[0222] For example, in the thickness direction Z of the wall portion 23, the distance between one end of the first surface 311b that is away from the electrode lead-out hole 231 and the second surface 232 is greater than the distance between one end of the first surface 311b that is close to the electrode lead-out hole 231 and the second surface 232.

[0223] When the internal pressure or temperature of the outer case 20 reaches a threshold, the inclined first surface 311b can induce deformation of the protrusion 311, making it easier for the protrusion 311 to be pulled out of the electrode pull-out hole 231, and reducing the pressure immediately, thereby improving the reliability of the battery cell 7.

[0224] In some embodiments, the protrusion 311 has a third surface 311c opposite the wall 23, and the third surface 311c is parallel to the second surface 232. The thickness of the protrusion 311 gradually decreases in the direction from the central axis X of the electrode lead-out hole 231 toward the outer circumferential edge 311a of the protrusion 311.

[0225] In some embodiments, the electrode terminal 30 includes a terminal body 32 and a first stopper portion 31 that are connected to each other, at least a portion of the terminal body 32 is housed in the electrode lead-out hole 231, and the first stopper portion 31 is located on the side of the wall portion 23 that faces the electrode assembly 10 and protrudes from an outer peripheral surface 321 of the terminal body 32. The first stopper portion 31 includes a protrusion 311.

[0226] The first stopper portion 31 may include only the protrusion 311, or may include other portions in addition to the protrusion 311.

[0227] There may be one or more first stopper portions 31. Optionally, there is one first stopper portion 31, and the first stopper portion 31 has a circular ring structure.

[0228] By placing the terminal body 32 so that it fits into the electrode lead-out hole 231, it becomes easier to connect the electrode terminal 30 to other components outside the battery cell 7. The wall 23 forms a barrier against the protrusion 311, thereby restricting the electrode terminal 30 from coming out of the interior of the outer case 20.

[0229] In some embodiments, the electrode terminal 30 further includes a second stopper portion 33 that protrudes from the outer peripheral surface 321 of the terminal body 32 and is located outside the wall portion 23. In the thickness direction Z of the wall portion 23, at least a portion of the wall portion 23 is located between the protrusion 311 and the second stopper portion 33.

[0230] The wall portion 23 is positioned between the first stopper portion 31 and the second stopper portion 33, thereby limiting the relative movement between the electrode terminal 30 and the wall portion 23.

[0231] In some embodiments, the end of the second stopper portion 33 remote from the terminal body 32 extends beyond the end of the first stopper portion 31 remote from the terminal body 32 in the radial direction of the electrode lead-out hole 231 .

[0232] In the radial direction of the electrode lead-out hole 231, the second stopper portion 33 has a larger dimension than the first stopper portion 31, which increases the exposed area of ​​the electrode terminal 30, facilitating connection between the electrode terminal 30 and an external bus member, increasing the connection area between the electrode terminal 30 and the bus member, and improving current passing capacity. In the radial direction of the electrode lead-out hole 231, the first stopper portion 31 has a larger dimension than the second stopper portion 33, which makes it easier to deform and quickly reduce pressure when the internal pressure or temperature of the outer case 20 reaches a threshold, improving the reliability of the battery cell 7.

[0233] In some embodiments, the first stopper portion 31, the second stopper portion 33, and the terminal body 32 are integrally molded. This embodiment can improve the overall structural strength of the electrode terminal 30, reduce the internal resistance of the electrode terminal 30, and improve the current passing capacity.

[0234] In some embodiments, the battery cell 7 further includes a sealing member 50, at least a portion of which is provided between the first stopper portion 31 and the wall portion .

[0235] For example, the electrode terminals 30 and the sealing member 50 together separate the internal space and the external space of the outer case 20, improving the sealing of the battery cells 7.

[0236] The seal member 50 can fill the gap between the first stopper portion 31 and the wall portion 23, thereby sealing the electrode lead-out hole 231.

[0237] In some embodiments, the seal member 50 is compressed and sandwiched between a portion of the first stopper portion 31 and the wall portion 23 to seal the electrode lead-out hole 231 .

[0238] In some embodiments, a portion of the seal member 50 is provided between the second stop portion 33 and the wall portion 23 .

[0239] In some embodiments, a portion of the sealing member 50 is provided in the electrode lead-out hole 231 and separates the hole wall 231 a of the electrode lead-out hole 231 from the terminal body 32 .

[0240] In some embodiments, the seal member 50 is made of an insulating material. The seal member 50 can insulate and separate the wall 23 and the electrode terminal 30.

[0241] In some embodiments, the battery cell 7 further includes an insulating member 60, which is provided on the surface of the wall 23 facing the electrode assembly 10. The insulating member 60 is used to insulate and separate at least a portion of the electrode assembly 10 from the wall 23.

[0242] In some embodiments, the projection of the wall 23 along its own thickness direction Z is annular. Optionally, the battery cell 7 is a cylindrical battery cell.

[0243] FIG. 9 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application, and FIG. 10 is a schematic view of an electrode terminal shown in FIG.

[0244] As shown in Figures 9 and 10, in some embodiments, the first stopper portion 31 is provided with a weak portion 313, and the first stopper portion 31 can bend or break along the weak portion 313 when the internal pressure or temperature of the outer case 20 reaches a threshold value.

[0245] The weak portion 313 is a portion of the first stopper portion 31 that is relatively weak and is easily broken or bent. For example, the strength of the weak portion 313 is weaker than the strength of a portion of the first stopper portion 31 that is adjacent to the weak portion 313.

[0246] In some examples, the present application may open a recess, shallow groove, through hole, or other structure in a predetermined region of the first stopper portion 31, thereby reducing the local strength of the first stopper portion 31 and forming a weak portion 313 in the first stopper portion 31. For example, a treatment may be performed to reduce the thickness of a predetermined region of the first stopper portion 31, thereby forming the weak portion 313 in the portion of the first stopper portion 31 that has been subjected to the treatment to reduce the thickness. In another example, a material treatment may be performed in a predetermined region of the first stopper portion 31, making the strength of that region weaker than the strength of the remaining regions, i.e., the region is the weak portion 313.

[0247] As an example, the entire weak portion 313 may be provided on the protruding portion 311, or a portion thereof may be provided on the protruding portion 311. As an alternative example, the entire weak portion 313 may be provided on a portion of the first stopper portion 31 other than the protruding portion 311.

[0248] By providing the weak portion 313 in the first stopper portion 31, when the internal pressure or temperature of the outer case 20 reaches a threshold, the first stopper portion 31 becomes less likely to deform, and can be bent or torn at a predetermined position, thereby connecting the internal space and external space of the outer case 20 through the electrode pull-out hole 231 and reducing the risk of the battery cell 7 exploding.

[0249] In some embodiments, at least a part of the projection of the weak portion 313 in the thickness direction Z of the wall portion 23 is located within the electrode lead-out hole 231 .

[0250] The projection of the weak portion 313 in the thickness direction Z at least partially overlaps with the projection of the electrode lead-out hole 231 in the thickness direction Z.

[0251] In the embodiment of the present application, when the internal pressure or temperature of the outer case 20 reaches a threshold value, the curved portion of the first stopper portion 31 is brought closer to the electrode pull-out hole 231, thereby making it easier to pull out the first stopper portion 31 from the electrode pull-out hole 231.

[0252] In some embodiments, the first stopper portion 31 includes a protrusion 311 and a connecting portion 312, the connecting portion 312 is used to connect the protrusion 311 and the terminal body 32, and the projection of the connecting portion 312 in the thickness direction Z of the wall portion 23 is located between the outer peripheral surface 321 of the terminal body 32 and the hole wall 231a of the electrode lead-out hole 231. The weak portion 313 is provided in the connecting portion 312.

[0253] In some examples, a portion of the connection portion 312 is the weakened portion 313, and in alternative embodiments, the entire connection portion 312 is the weakened portion 313.

[0254] The projection of the weak portion 313 in the thickness direction Z of the wall portion 23 is positioned entirely within the electrode lead-out hole 231 .

[0255] For example, when the internal pressure or temperature of the outer case 20 reaches a threshold, the protrusion 311 can bend inverted along with the bending of the weak portion 313, thereby releasing the wall portion 23 and being pulled out from the electrode pull-out hole 231. In the embodiment of the present application, the weak portion 313 is provided in the connection portion 312, which relaxes the restriction on the strength of the protrusion 311 and makes the shape design of the protrusion 311 more flexible.

[0256] For example, when the internal pressure or temperature of the outer case 20 reaches a threshold value, the first stopper portion 31 breaks along the weak portion 313, whereby the wall portion 23 is no longer restrained by the terminal body 32 via the protrusion 311, and the terminal body 32 can be pulled out from the electrode pull-out hole 231.

[0257] In some embodiments, the electrode terminal 30 has a shallow groove 314, and the weak portion 313 is formed at the bottom of the shallow groove 314. By forming the weak portion 313 by opening the shallow groove 314, the molding efficiency of the electrode terminal 30 can be improved.

[0258] In some embodiments, the shallow groove 314 is provided on the surface of the first stopper portion 31 opposite the wall portion 23 .

[0259] When the internal pressure or temperature of the outer case 20 reaches a threshold, the shallow groove 314 provides a space for the material to flow and helps to bend the first stopper portion 31 .

[0260] FIG. 11 is a schematic cross-sectional view of an electrode terminal of a battery cell according to another embodiment of the present invention.

[0261] As shown in FIG. 11, in some embodiments, the shallow groove 314 is provided in the surface of the first stopper portion 31 facing the wall portion 23 .

[0262] In some embodiments, the surface of the first stopper 31 opposite the wall 23 abuts against the current collecting member 40. A shallow groove 314 is provided on the surface of the first stopper 31 facing the wall 23, which can reduce the effect of the shallow groove 314 on the contact area between the first stopper 31 and the current collecting member 40, thereby improving current passing capacity.

[0263] In some embodiments, a portion of the seal member 50 fills the shallow groove 314 .

[0264] In some embodiments, a shallow groove 314 is provided on the surface of the first stopper portion 31 facing the wall portion 23, and a shallow groove 314 is also provided on the surface of the first stopper portion 31 opposite the wall portion 23, and a weak portion 313 is formed between the two shallow grooves 314.

[0265] FIG. 12 is a schematic cross-sectional view of a battery cell according to some embodiments of the present application, and FIG. 13 is a schematic cross-sectional view of an electrode terminal shown in FIG.

[0266] 12 and 13 , in some embodiments, a recess 34 is provided in the electrode terminal 30. The recess 34 is recessed from the inside of the outer case 20 toward the outside of the outer case 20 along the thickness direction Z of the wall portion 23. At least a portion of the recess 34 is provided on the side of the terminal body 32 facing the tab 11.

[0267] When the internal pressure or temperature of the outer case 20 reaches a threshold value, the first stopper portion 31 is bent, and the recess 34 can provide space for material to flow during the bending process of the first stopper portion 31, thereby reducing the resistance to bending of the first stopper portion 31 and allowing the first stopper portion 31 to be immediately pulled out of the electrode pull-out hole 231.

[0268] In some embodiments, the recess 34 includes a first side 341 and a second side 342, the first side 341 being arranged along the radial outer side of the electrode lead-out hole 231 of the second side 342, the first side 341 being connected to the bottom surface 343 of the recess 34, and being inclined toward the side away from the central axis Y of the electrode terminal 30.

[0269] For example, the first side surface 341 being provided outside the second side surface 342 may mean that the first side surface 341 is located on the side of the second side surface 342 that is away from the central axis Y of the electrode terminal 30 along the radial direction of the electrode lead-out hole 231.

[0270] The bottom surface 343 of the recess 34 may be a flat surface or a curved surface. Illustratively, the first side surface 341 and the second side surface 342 are connected to both ends of the bottom surface 343, respectively.

[0271] For example, the central axis Y of the electrode terminal 30 may be parallel to the central axis X of the electrode lead-out hole 231 .

[0272] Alternatively, the central axis Y of the electrode terminal 30 may overlap with the central axis X of the electrode lead-out hole 231, and of course, due to process errors, the central axis Y of the electrode terminal 30 may be offset by a certain distance from the central axis X of the electrode lead-out hole 231.

[0273] By setting the first side surface 341 at an angle, more space can be provided for the material to flow when the first stopper portion 31 is bent, thereby reducing the resistance to bending of the first stopper portion 31.

[0274] In some embodiments, the recess 34 includes a first side 341 and a second side 342, the first side 341 being arranged along the radial outer side of the electrode lead-out hole 231 of the second side 342, and the second side 342 being connected to the bottom surface 343 of the recess 34 and being inclined toward the side closer to the central axis Y of the electrode terminal 30.

[0275] By setting the second side 342 at an angle, the risk of interference between the second side 342 and the first side 341 is reduced when the first side 341 is deformed due to the flow of material, and the resistance to bending of the first stopper portion 31 is reduced.

[0276] In some embodiments, the first side 341 is connected to the bottom surface 343 of the recess 34 and is inclined toward the side away from the central axis Y of the electrode terminal 30, and the second side 342 is connected to the bottom surface 343 of the recess 34 and is inclined toward the side closer to the central axis Y of the electrode terminal 30.

[0277] In some embodiments, the first stopper portion 31 can bend toward the recess 34 when the internal pressure or temperature of the outer case 20 reaches a threshold value.

[0278] When the internal pressure or temperature of the outer case 20 reaches a threshold value, the first stopper portion 31 bends toward the recess 34, causing the material to flow toward the recess 34, reducing the resistance to bending of the first stopper portion 31, and allowing the first stopper portion 31 to be immediately pulled out from the electrode pull-out hole 231.

[0279] In some embodiments, the first stopper portion 31 is formed by folding back a part of the electrode terminal 30 .

[0280] When assembling, the electrode terminal 30 can be inserted into the outer case 20 through the electrode pull-out hole 231, and then a portion of the electrode terminal 30 is folded back to form the first stopper portion 31, thereby fixing the electrode terminal 30 to the wall portion 23.

[0281] In some embodiments, when the electrode terminal 30 is inserted into the outer case 20 from the outside through the electrode pull-out hole 231, the electrode terminal 30 may be pressed from the inside, thereby bending a portion of the electrode terminal 30 and forming a flange-shaped first stopper portion 31.

[0282] A recess 34 may be formed in the electrode terminal 30 at a location that is pressed by an external workpiece.

[0283] In some embodiments, the terminal body 32 includes a terminal protrusion 322, and the recess 34 is disposed around the terminal protrusion 322. In the thickness direction Z of the wall portion 23, an end surface 322a of the terminal protrusion 322 facing the tab 11 is closer to the tab 11 than the first stopper portion 31.

[0284] In the embodiment of the present application, the first stopper portion 31 is less likely to interfere with the contact between the terminal protrusion 322 and other components (e.g., the tab 11 or the current collecting member 40), thereby reducing excessive positioning and the risk of poor contact between the terminal protrusion 322 and other components due to unevenness of the first stopper portion 31, thereby improving the current passing capacity and reliability of the battery cell 7.

[0285] FIG. 14 is a schematic cross-sectional view of an electrode terminal of a battery cell according to another embodiment of the present invention.

[0286] As shown in FIG. 14, in some embodiments, a recess 34 is provided on the side of the terminal body 32 facing the tab 11, and a thinned portion 313 is provided in the first stopper portion 31.

[0287] By simultaneously installing the weak portion 313 and the recess 34, when the internal pressure or temperature of the outer case 20 reaches a threshold value, the resistance force of the first stopper portion 31 against bending can be further reduced, and the first stopper portion 31 can be immediately pulled out from the electrode pull-out hole 231.

[0288] FIG. 15 is a schematic cross-sectional view of a local portion of a battery cell according to another embodiment of the present invention, and FIG. 16 is a schematic cross-sectional view of an electrode terminal shown in FIG.

[0289] As shown in Figures 15 and 16, in some embodiments, the electrode terminal 30 includes a terminal body 32, a first stopper portion 31, and a second stopper portion 33, at least a portion of the terminal body 32 is accommodated in the electrode pull-out hole 231, the first stopper portion 31 is located on the side of the wall portion 23 facing the electrode assembly 10 and protrudes from the outer peripheral surface 321 of the terminal body 32, the second stopper portion 33 is located on the side of the wall portion 23 opposite the electrode assembly 10 and protrudes from the outer peripheral surface 321 of the terminal body 32, and in the thickness direction Z, at least a portion of the wall portion 23 is sandwiched between the first stopper portion 31 and the second stopper portion 33.

[0290] In some embodiments, the first stop portion 31 is provided with a shallow groove 314 to form the weakened portion 313 .

[0291] In some embodiments, the terminal body 32 has a through-hole 323 for injecting an electrolyte. In some embodiments, the electrode terminal 30 further includes a sealing plate 35, which is connected to the terminal body 32 and seals the through-hole 323.

[0292] In some embodiments, the terminal body 32 , the first stopper portion 31 and the second stopper portion 33 are of one piece, and the sealing plate 35 is welded to the terminal body 32 .

[0293] In some embodiments, the through hole 323 is a stepped hole, and at least a portion of the sealing plate 35 is received within the through hole 323 and abuts against the stepped surface.

[0294] FIG. 17 is a schematic diagram of the three-dimensional structure of a battery cell according to another embodiment of the present invention.

[0295] As shown in FIG. 17, in some embodiments, the projection of the wall 23 along its own thickness direction Z is rectangular.

[0296] In some embodiments, the battery cells 7 are prismatic battery cells.

[0297] In some embodiments, the wall 23 is an end cover 22 .

[0298] According to some embodiments of the present application, the present application further provides a battery including a plurality of battery cells 7 of any of the above embodiments.

[0299] According to some embodiments of the present application, the present application further provides a power consuming device including the battery cell 7 of any of the above embodiments used to supply electrical energy. The power consuming device may be a device or system that uses any of the battery cells 7.

[0300] 5 to 8, an embodiment of the present application provides a cylindrical battery cell 7 including an outer case 20, an electrode assembly 10, an electrode terminal 30, a current collecting member 40, and a sealing member 50.

[0301] The outer case 20 includes a housing 21 and an end cover 22. One end of the housing 21 has an opening, which is covered by the end cover 22. The housing 21 includes a side wall 212 and an end wall 211. The side wall 212 surrounds the outside of the electrode assembly 10, and the end wall 211 is disposed opposite the opening. An electrode lead-out hole 231 is formed in the end wall 211.

[0302] The electrode assembly 10 is housed in an outer case 20 and includes a tab 11 , and the electrode terminal 30 is mounted on the end wall 211 and electrically connected to the tab 11 via a current collecting member 40 .

[0303] The electrode terminal 30 includes a terminal body 32, a first stopper portion 31 and a second stopper portion 33, at least a portion of the terminal body 32 is accommodated in the electrode pull-out hole 231, the first stopper portion 31 is located on the side of the end wall 211 facing the electrode assembly 10 and protrudes from the outer peripheral surface 321 of the terminal body 32, the second stopper portion 33 is located on the side of the end wall 211 opposite the electrode assembly 10 and protrudes from the outer peripheral surface 321 of the terminal body 32, and in the thickness direction Z, at least a portion of the end wall 211 is located between the first stopper portion 31 and the second stopper portion 33.

[0304] The seal member 50 separates the electrode terminal 30 from the end wall 211, and the electrode terminal 30 and the seal member 50 together cover the electrode lead-out hole 231, thereby sealing the electrode lead-out hole 231.

[0305] When the internal pressure or temperature of the outer case 20 reaches a threshold value, the first stopper portion 31 can bend and deform, and the entire electrode terminal 30 is detached from the end wall 211, thereby connecting the internal space and the external space of the outer case 20 through the electrode pull-out hole 231, and discharging the gas inside the outer case 20.

[0306] Although the present application has been described with reference to preferred embodiments, various modifications may be made and the elements may be replaced with equivalents without departing from the scope of the present application, and in particular, the technical features mentioned in each embodiment may be combined in any manner as long as there is no structural contradiction. 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. an outer case including a wall portion provided with an electrode lead-out hole; an electrode assembly at least partially contained within the outer case and including a tab; an electrode terminal that is installed on the wall portion, covers at least a portion of the electrode lead-out hole, and is electrically connected to the tab, a battery cell in which at least a portion of the electrode terminal is deformable when the internal pressure or temperature of the outer case reaches a threshold value so as to communicate the internal space and the external space of the outer case through the electrode lead-out hole and to discharge gas from inside the outer case.

2. The battery cell according to claim 1 , wherein at least a portion of the electrode terminal is capable of detaching from the wall portion when the internal pressure or temperature of the outer case reaches the threshold value.

3. 3. The battery cell according to claim 1, wherein the electrode terminal includes a protrusion that protrudes from a wall of the electrode lead-out hole along a radial direction of the electrode lead-out hole, the protrusion being located on a side of the wall facing the electrode assembly, and the protrusion being deformable when the internal pressure or temperature of the outer case reaches the threshold value.

4. When the maximum dimension of the protrusion protruding from the wall of the electrode lead-out hole is L1 and the minimum distance between the periphery of the wall portion and the wall of the electrode lead-out hole is L2, The battery cell according to claim 3 , wherein L1 and L2 satisfy 0.1≦L1 / L2≦0.

5.

5. When the maximum dimension of the protrusion protruding from the wall of the electrode lead-out hole is L1 and the maximum thickness of the protrusion is T1, L1 and T1 are 0.25 mm ２ ≦L1×T1≦25mm ２ The battery cell according to claim 3 or 4, which satisfies the above.

6. The battery cell of claim 5 , wherein T1 is 0.5 mm to 5 mm.

7. 7. The battery cell according to claim 3, wherein the thickness of at least a portion of the protrusion gradually decreases in a direction from the central axis of the electrode lead-out hole toward the outer circumferential edge of the protrusion.

8. 8. The battery cell according to claim 3, wherein the protrusion has a first surface facing the wall, the wall has a second surface facing the protrusion, the second surface is perpendicular to a thickness direction of the wall, the first surface is inclined relative to the second surface in a direction approaching the electrode assembly, and a distance between one end of the first surface away from the electrode lead-out hole and the second surface in the thickness direction of the wall is greater than a distance between one end of the first surface close to the electrode lead-out hole and the second surface.

9. the electrode terminal includes a terminal body and a first stopper portion connected to each other, at least a portion of the terminal body is accommodated in the electrode lead-out hole, and the first stopper portion is located on a side of the wall portion facing the electrode assembly and protrudes from an outer peripheral surface of the terminal body; The battery cell according to any one of claims 3 to 8, wherein the first stopper portion includes the protrusion.

10. The battery cell of claim 9 , wherein the first stopper portion has a weak portion, and the first stopper portion is capable of bending or breaking along the weak portion when the internal pressure or temperature of the outer case reaches the threshold value.

11. The battery cell according to claim 10 , wherein at least a portion of the projection of the weak portion in the thickness direction of the wall portion is located within the electrode lead-out hole.

12. the first stopper portion includes a protrusion and a connection portion, the connection portion is used to connect the protrusion and the terminal body, and a projection of the connection portion in a thickness direction of the wall portion is located between an outer peripheral surface of the terminal body and a hole wall of the electrode lead-out hole, The battery cell according to claim 11 , wherein the weakened portion is provided at the connection portion.

13. The battery cell according to any one of claims 10 to 12, wherein a shallow groove is provided in the electrode terminal, and the weakened portion is formed at a bottom of the shallow groove.

14. the shallow groove is provided on a surface of the first stopper portion facing the wall portion, and / or The battery cell according to claim 13 , wherein the shallow groove is provided on a surface of the first stopper portion opposite the wall portion.

15. 12. The battery cell according to claim 10, wherein the electrode terminal has a recess, the recess is recessed from the inside of the outer case toward the outside of the outer case along the thickness direction of the wall portion, and at least a portion of the recess is provided on a side of the terminal body facing the tab.

16. 16. The battery cell of claim 15, wherein the recess includes a first side surface and a second side surface, the first side surface being provided along a radially outer side of the electrode lead-out hole of the second side surface, the first side surface being connected to a bottom surface of the recess, and being inclined toward a side away from a central axis of the electrode terminal.

17. 16. The battery cell of claim 15, wherein the recess includes a first side surface and a second side surface, the first side surface being provided along a radially outer side of the electrode lead-out hole of the second side surface, and the second side surface being connected to a bottom surface of the recess and being inclined toward a side closer to a central axis of the electrode terminal.

18. The battery cell according to any one of claims 15 to 17, wherein the first stopper portion is capable of bending in a direction approaching the recess when the internal pressure or temperature of the outer case reaches the threshold value.

19. The battery cell according to any one of claims 15 to 18, wherein the first stopper portion is formed by folding back a part of the electrode terminal.

20. The terminal body includes a terminal protrusion, and the recess is disposed around the terminal protrusion; The battery cell according to any one of claims 15 to 19, wherein, in the thickness direction of the wall portion, an end face of the terminal protrusion that faces the tab is closer to the tab than the first stopper portion.

21. The electrode terminal further includes a second stopper portion, the second stopper portion protruding from an outer circumferential surface of the terminal body and disposed outside the wall portion; The battery cell according to any one of claims 9 to 20, wherein at least a portion of the wall is located between the protrusion and the second stopper in a thickness direction of the wall.

22. The battery cell according to claim 21 , wherein an end of the second stopper portion remote from the terminal body in the radial direction of the electrode lead-out hole exceeds an end of the first stopper portion remote from the terminal body.

23. The battery cell according to claim 21 or 22, wherein the first stopper portion, the second stopper portion, and the terminal body are integrally molded.

24. The battery cell according to any one of claims 9 to 23, further comprising a sealing member, at least a portion of the sealing member being provided between the first stopper portion and the wall portion.

25. The battery cell according to any one of claims 1 to 24, wherein the electrode terminal has a melting point lower than the melting point of the wall portion.

26. 26. The battery cell according to claim 25, wherein H2-H1≧300° C., where H1 is the melting point of the electrode terminal and H2 is the melting point of the wall portion.

27. The battery cell according to any one of claims 1 to 26, wherein the material of the electrode terminals includes aluminum or copper, and the material of the wall portion includes steel.

28. The battery cell of any one of claims 1 to 27, wherein the outer case includes a housing and an end cover, one end of the housing has an opening, the end cover covers the opening, the housing includes side walls and end walls, the side walls surround the outside of the electrode assembly, the end walls are located opposite the opening, and the wall portion is the end cover or the end wall.

29. The battery cell according to any one of claims 1 to 28, wherein the wall portion has a rectangular or annular shape when projected along its own thickness direction.

30. A battery comprising a plurality of battery cells according to any one of claims 1 to 29.

31. 31. A power consuming device comprising the battery of claim 30 for supplying electrical energy thereto.

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