Battery cells, batteries and power consuming devices

Abstract

This application provides a battery cell, a battery, and a power consuming device in the field of battery technology. The battery cell includes a housing, an electrode assembly, and an electrode terminal. The housing includes a wall portion having an extraction hole. The electrode assembly is accommodated within the housing and includes an active material application portion and a tab. The tab is attached to an end of the active material application portion facing the wall portion. The electrode terminal includes a terminal body and a limiting portion. The terminal body is drilled into the extraction hole, and the limiting portion includes a first extension portion protruding from the outer surface of the terminal body along a first direction. The tab includes a first connecting portion and a second connecting portion. The second connecting portion is located on the side of the first connecting portion along the first direction, and the first connecting portion is connected to the active material application portion, and the second connecting portion is connected to the first extension portion. This structure shortens the length of the second connecting portion, thereby shortening the length of the tab. This reduces the possibility of tab misalignment and wrinkles during manufacturing, improving the reliability of the battery cell.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to Chinese Patent Application No. 2023106406111, entitled "Battery Cell, Battery and Power Consumption Device," filed on May 31, 2023, the entire contents of which are incorporated herein by reference.

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

[0003] BACKGROUND ART With the development of new energy technology, batteries are increasingly being applied in mobile phones, notebook computers, electric motorcycles, electric cars, electric airplanes, electric boats, electric car toys, electric boat toys, electric airplane toys, power tools, etc.

[0004] For general battery cells, the size of the battery cell can be increased to achieve the required high capacity, but as the size of the battery cell increases, the reliability of the battery cell may decrease. Therefore, when designing a battery cell, it is necessary to consider not only the capacity of the battery cell but also its reliability. Therefore, how to extend the service life of battery cells is an urgent issue in battery technology that needs to be resolved. Summary of the Invention

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

[0006] In a first aspect, the present application provides a battery cell, the battery cell comprising: a housing, an electrode assembly, and an electrode terminal; the housing includes a wall portion having an extraction hole; the electrode assembly is accommodated within the housing and includes an active material application portion and a tab; the tab is installed at an end of the active material application portion facing the wall portion; the electrode terminal includes a terminal body and a limiting portion; the terminal body is drilled in the extraction hole; the limiting portion is configured to limit removal of the terminal body from the extraction hole in a direction away from the active material application portion; the limiting portion includes a first extension portion protruding from an outer peripheral surface of the terminal body along a first direction; the tab includes a first connecting portion and a second connecting portion; the second connecting portion is located on a side of the first connecting portion along the first direction; the first connecting portion is connected to the active material application portion; and the second connecting portion is connected to the first extension portion.

[0007] In the above technical solution, the second connection portion is located on the side of the first connection portion along the first direction, and the second connection portion is connected to the first extension portion that protrudes from the outer surface of the terminal body along the first direction of the limiting portion, thereby shortening the length of the second connection portion and thereby shortening the length of the tab, reducing the possibility of tab misalignment and wrinkles during manufacturing and improving the reliability of the battery cell.

[0008] In some embodiments, the limiting portion further includes a second extension portion protruding from the outer peripheral surface of the terminal body in a direction opposite to the first direction, wherein a distance along the first direction between an end of the second extension portion away from the terminal body and a central axis of the terminal body is a first distance, the first extension portion includes an extension region, the distance between the extension region and the central axis is equal to or greater than the first distance, and the second connecting portion is connected to the extension region. By providing the extension region, the length of the first extension portion along the second direction is increased, and the second extension portion is elongated in the direction away from the terminal body. Because the second connecting portion is connected to the extension region, the second connecting portion is further separated from the terminal body along the first direction, thereby shortening the second connecting portion and advantageously further shortening the length of the tab.

[0009] In some embodiments, the distance along the first direction between the end of the second connecting portion proximal to the terminal body and the central axis is a second distance, the second distance being equal to or greater than the first distance, such that the end of the second connecting portion proximal to the terminal body is further away from the terminal body along the first direction, further shortening the length of the second connecting portion and thereby further shortening the length of the tab.

[0010] In some embodiments, the first connection portion faces a middle position of the active material application portion along the first direction, and / or the terminal body faces a middle position of the active material application portion along the first direction. When the first connection portion faces a middle position of the active material application portion along the first direction, the tab is positioned at the center before being folded, which is advantageous for forming the tab and reduces the difficulty of forming the tab. When the terminal body faces a middle position of the active material application portion along the first direction, the terminal body is positioned at the center, which is advantageous for connecting the electrode terminal to an external member and facilitating the output or input of electrical energy.

[0011] In some embodiments, the tab further includes a third connection portion and a fourth connection portion, and the first connection portion, the third connection portion, the fourth connection portion, and the second connection portion are sequentially connected, and the second connection portion and the third connection portion are disposed opposite each other along the axial direction of the terminal body. In this manner, the tab is bent between the active material-coated portion and the electrode terminal, reducing the internal space of the battery cell occupied by the tab and providing more space for the active material-coated portion, which is advantageous for improving the energy density of the battery cell.

[0012] In some embodiments, the second connection portion is connected to the side of the first extension portion facing the active material application portion along the axial direction of the terminal body, thereby reducing the distance between the second connection portion and the active material application portion in the axial direction of the terminal body, and effectively reducing the length of the tab.

[0013] In some embodiments, the terminal body and the limiting portion are integrally molded, which increases the connection strength between the terminal body and the limiting portion, making the terminal body and the limiting portion more rigid, reducing the possibility of the terminal body separating from the limiting portion due to impact forces during normal use of the battery cell, and reducing the possibility of failure of the battery cell during normal use.

[0014] In some embodiments, the battery cell further includes a first insulating member, the first insulating member including a first insulating portion disposed between the first extension portion and the wall portion in the axial direction of the terminal body, and a heat insulating structure disposed on a side of the first insulating portion facing the first extension portion and / or a side of the first extension portion facing the first insulating portion. The heat insulating structure serves a thermal insulation role, delaying or preventing heat transfer between the first extension portion and the first insulating portion, reducing the possibility of melting of the first insulating portion due to heat transfer from the first extension portion to the first insulating portion and reducing the possibility of insulation failure of the first insulating portion.

[0015] In some embodiments, the thermal insulation structure includes a relief groove provided in the first insulating portion and / or the first extending portion. This allows the thermal insulation structure to be simplified and easier to mold. Furthermore, by providing the relief groove, the first extending portion and the first insulating portion are less likely to come into direct contact in the area corresponding to the relief groove, thereby providing excellent thermal insulation.

[0016] In some embodiments, the second connection portion is welded to the first extension portion to form a weld mark area, and the orthogonal projections of the weld mark area and the relief groove in a plane perpendicular to the axial direction of the terminal body at least partially overlap. When the second connection portion is welded to the first extension portion, a large amount of heat is generated in the weld mark area of ​​the first extension portion, thereby increasing the temperature of the first extension portion. Since the orthogonal projections of the weld mark area and the relief groove in a plane perpendicular to the axial direction of the terminal body at least partially overlap, the relief groove can provide excellent heat insulation and reduce the impact of the first extension portion and the second connection portion on the first insulating portion during the welding process.

[0017] In some embodiments, the area of ​​the orthogonal projection of the weld mark region on the plane is S1, and the area of ​​the overlapping area of ​​the orthogonal projection of the weld mark region and the relief groove on the plane is S2, satisfying S2 / S1 ≥ 1 / 3. In this way, the area of ​​the overlapping area of ​​the orthogonal projection of the weld mark region and the relief groove on the plane accounts for a larger proportion of the area of ​​the orthogonal projection of the weld mark region on the plane, and the relief groove can block more of the heat generated in the weld mark region during the welding process by the first extension, thereby improving the ability of the relief groove to block heat from the weld mark region.

[0018] In some embodiments, S2 / S1≧1 / 2, which further increases the ratio of S2 to S1, further improving the heat insulating ability of the relief groove against the heat in the weld scar area.

[0019] In some embodiments, the first extension portion is formed with a fusing portion, so that when the current passing through the first extension portion is too large, the fusing portion can fuse itself to provide overcurrent protection for the battery cell.

[0020] In some embodiments, the first extension portion has a through hole, and both ends of the through hole extend to two opposing surfaces of the first extension portion along the axial direction of the terminal body to form adjacent fusion sections. The fusion sections are formed adjacent to each other by providing the through hole in the first extension portion, which simplifies the fusion section formation method. After providing the through hole in the first extension portion, the cross-sectional area of ​​the formed fusion section is smaller than the cross-sectional area of ​​the rest of the first extension portion. As a result, the resistance of the fusion section is greater than the resistance of the rest of the first extension portion. If the current passing through the first extension portion is too large, the fusion section will generate heat and melt.

[0021] In some embodiments, the first extension portion has a plurality of through holes arranged at intervals along a second direction, the second direction intersecting the first direction. When the current passing area of ​​the fusing portion is constant, the first extension portion has a plurality of through holes, which can make the through holes smaller and reduce the difficulty of forming the through holes.

[0022] In some embodiments, the first extension portion has two through holes, each extending along the second direction to one end of the first extension portion, and the fusing portion is located between the two through holes. In this way, since only one fusing portion is formed in the first extension portion, it is easier to control the current passing area of ​​the fusing portion, the electrode terminal structure is simplified, and the difficulty of forming the electrode terminal is reduced.

[0023] In some embodiments, the battery cell further includes a second insulating member that covers at least a portion of the outer surface of the fusing portion. The second insulating member serves as an insulator, reducing the risk of the electrode terminal conducting electrical current between the positive electrode sheet and the negative electrode sheet after the fusing portion is blown.

[0024] In some embodiments, the second insulating member includes an insulating coating disposed on the outer surface of the fusing portion, an insulating adhesive layer bonded to the outer surface of the fusing portion, or a thermally welded insulating layer bonded to the outer surface of the fusing portion. The insulating coating is a coating disposed on the outer surface of the fusing portion, and is thin and occupies a small space. The insulating adhesive layer may be bonded to the fusing portion, which can improve assembly efficiency and reduce manufacturing costs. The thermally welded insulating layer may be thermally welded to the fusing portion. In this case, the thermally welded insulating layer not only provides insulation after the fusing portion is fused, but also plays a limiting role, maintaining the original shape of the electrode terminal and reducing the possibility of contact between the electrode terminal and the electrode sheet of the active material coating portion after the fusing portion is fused, thereby reducing the possibility of a short circuit occurring inside the battery cell.

[0025] In some embodiments, the second insulating member includes a second insulating portion and a third insulating portion, the second insulating portion and the third insulating portion defining a first space, the fusing portion being housed in the first space, and the second insulating portion and the third insulating portion being removably connected. This allows for easy installation and removal of the second insulating member. The second insulating member having this structure not only provides insulation after the fusing portion has blown, but also plays a restricting role, maintaining the original shape of the electrode terminal and reducing the possibility of contact between the electrode terminal and the electrode sheet at the active material coating portion after the fusing portion has blown, thereby reducing the possibility of a short circuit occurring inside the battery cell.

[0026] In some embodiments, the second insulating part is provided with a first locking part, and the third insulating part is provided with a second locking part, and the first locking part and the second locking part are fitted together. When attaching the second insulating part, the second insulating part and the third insulating part can be connected by fitting the first locking part into the second locking part, and the second insulating part and the third insulating part can be separated by releasing the engagement between the first locking part and the second locking part, thereby easily attaching and detaching the second insulating part and the third insulating part.

[0027] In some embodiments, the limiting portion is provided with a weight reduction structure, which can reduce the weight of the electrode terminal, thereby reducing the weight of the battery cell.

[0028] In some embodiments, the weight reduction structure includes a weight reduction hole disposed in the restriction portion, and both ends of the weight reduction hole extend along two opposite faces of the restriction portion in the axial direction of the terminal body. By disposing the weight reduction hole in the restriction portion, the weight of the electrode terminal can be reduced and easily achieved.

[0029] In some embodiments, the weight reduction structure includes a plurality of weight reduction holes, the plurality of weight reduction holes being arranged around the periphery of the terminal body, and by arranging the plurality of weight reduction holes in the limiting portion, the weight of the electrode terminal can be further reduced.

[0030] In some embodiments, weight reduction holes are provided at the four corners of the restriction part, which can further reduce the weight of the electrode terminal and less affect the current passing through the electrode terminal.

[0031] In some embodiments, the weight-reducing hole is provided in the first extension portion to form a corresponding fusing portion, and the weight of the electrode terminal can be reduced by providing the weight-reducing hole in the first extension portion and forming the fusing portion.

[0032] In some embodiments, the housing includes a case and an end cover, the case having an opening, the end cover sealing the opening, and the end cover being a wall. This allows, when assembling the battery cell, first attaching the electrode terminals to the end cover, then connecting the tabs to the electrode terminals, then housing the electrode assembly in the case, and finally connecting the end cover to the case to seal the opening of the case. This structure makes it easier to attach the electrode terminals and connect the tabs to the electrode terminals.

[0033] According to a second aspect, an embodiment of the present application provides a battery, the battery comprising a battery cell according to any one of the embodiments of the first aspect.

[0034] According to a third aspect, an embodiment of the present application provides a power consumer device, the power consumer device comprising a battery cell according to any one of the embodiments of the first aspect above for supplying electrical energy to the power consumer device. [Brief explanation of the drawings]

[0035] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly describes the drawings that need to be used in the embodiments. It should be understood that the following drawings only illustrate some embodiments of the present application, and should not be considered as limiting the scope, and those skilled in the art can obtain other related drawings based on these drawings without any creative efforts.

[0036] [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Figure 2] FIG. 1 is an exploded view of a battery according to some embodiments of the present application. [Figure 3] FIG. 1 is an exploded view of a battery cell according to some embodiments of the present application. [Figure 4] FIG. 1 is a partial view of a battery cell according to some embodiments of the present application. [Figure 5] FIG. 5 is a partial enlarged view of a portion A in FIG. 4. [Figure 6] FIG. 5 is an axonometric view of the electrode terminal shown in FIG. [Figure 7] FIG. 7 is a top view of the electrode terminal shown in FIG. [Figure 8] FIG. 2 is a partial view of a battery cell according to some other embodiments of the present application. [Figure 9] FIG. 9 is a structural schematic diagram of the electrode terminal shown in FIG. 8. [Figure 10] FIG. 9 is a partial enlarged view of a portion B in FIG. 8. [Figure 11] FIG. 11 is an axonometric view of the electrode terminal shown in FIG. [Figure 12] 10 is an axonometric view of an electrode terminal according to some further embodiments of the present application. [Figure 13] FIG. 10 is an axonometric view of an electrode terminal and a second insulating member after they are connected together according to some embodiments of the present application. [Figure 14] 14 is a cross-sectional view of the electrode terminal shown in FIG. 13 after being connected to the second insulating member. FIG. [Figure 15] 10 is an axonometric view of an electrode terminal and a second insulating member according to some other embodiments of the present application after they are connected to each other. FIG. [Figure 16] 10 is an axonometric view of an electrode terminal and a second insulating member according to still other embodiments of the present application after they are connected to each other. FIG. [Figure 17] 17 is a schematic diagram of the structure after the electrode terminal and the second insulating member shown in FIG. 16 are connected. [Figure 18] 18 is a cross-sectional view taken along line CC after the electrode terminal and the second insulating member shown in FIG. 17 are connected. [Figure 19] 10 is an axonometric view of an electrode terminal according to still other embodiments of the present application.

[0037] DESCRIPTION OF SYMBOLS: 1—housing, 11—case, 12—end cover, 13—wall portion, 131—drawing hole, 2—electrode assembly, 21—active substance application portion, 22—tab, 221—first connection portion, 222—second connection portion, 223—tab root portion, 224—third connection portion, 225—fourth connection portion, 3—electrode terminal, 31—terminal body, 311—outer circumferential surface, 312—central axis, 32—limiting portion, 321—first extension portion, 3211—extension region, 3212—connection region, 3213—first surface, 3214—second surface, 3215—undercut groove, 3216—weld mark region, 3217—fused portion, 3218 - through hole, 322 - first cross section, 323 - second extension portion, 324 - second cross section, 235 - third cross section, 326 - weight reduction hole, 4 - third insulating member, 5 - connecting member, 6 - fourth insulating member, 7 - sealing member, 8 - first insulating member, 81 - first insulating member, 9 - second insulating member, 91 - second insulating member, 911 - first fastening portion, 92 - third insulating member, 921 - second fastening portion, 93 - first space, 10 - battery cell, 20 - housing, 201 - first part, 202 - second part, 100 - battery, 200 - controller, 300 - motor, 1000 - vehicle, X - first direction, Y - second direction, Z - axis direction. DETAILED DESCRIPTION OF THE INVENTION

[0038] In order to clarify the objectives, technical solutions and advantages of the embodiments of the present application, the following will clearly describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. It is clear that the described embodiment is one embodiment of the present application, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without any creative effort are within the scope of protection of the present application.

[0039] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the art. Terms used in this application are intended to describe specific embodiments only and are not intended to limit this application. Any variations of the terms "comprise" and "have" in the specification and claims of this application and the brief description of the drawings are intended to cover a non-exclusive "comprise." Terms such as "first," "second," etc. in the specification and claims of this application or the drawings are not intended to describe a particular order or hierarchy, but are intended to distinguish between different objects.

[0040] An "embodiment" referred to in this application means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of this phrase in various places in the specification do not necessarily all refer to the same embodiment, nor are they mutually exclusive, separate, or alternative embodiments of other embodiments.

[0041] 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 are in an "or" relationship.

[0042] 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 thickness, length, width, and other dimensions of various elements in the embodiments of the present application shown in the drawings, and the overall thickness, length, width, and other dimensions of the integrated device, are illustrative only and do not constitute any limitations on the present application.

[0043] The term "plurality" as used herein refers to two or more (including two).

[0044] In the embodiment of the present application, the battery cell may be a secondary battery, which refers to a battery cell that can be continuously used after being discharged by activating the active material through charging.

[0045] Battery cells include, but are not limited to, lithium ion batteries, sodium ion batteries, sodium lithium ion batteries, lithium metal batteries, sodium metal batteries, lithium sulfur batteries, magnesium ion batteries, nickel metal hydride batteries, nickel cadmium batteries, lead acid batteries, and the like.

[0046] A battery cell generally includes an electrode assembly, which 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 electrode and the negative electrode while allowing the active ions to pass through.

[0047] 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.

[0048] For example, the positive electrode current collector has two surfaces that face each other in the thickness direction thereof, and the positive electrode active material is disposed on one or both of the two facing surfaces of the positive electrode current collector.

[0049] For example, the positive electrode current collector can be a metal foil sheet or a composite current collector. For example, the metal foil sheet can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, a carbon electrode, carbon, nickel, or titanium. The composite current collector can include a polymeric material base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) on a polymeric material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, or polyethylene).

[0050] 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. Here, examples of the lithium-containing phosphate may include, but are not limited to, at least one of lithium iron phosphate (e.g., LiFePO4 (also abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon. Examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO), lithium nickel oxide (e.g., LiNiO), lithium manganese oxide (e.g., LiMnO, LiMnO), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (e.g., LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM 333 (may be abbreviated as "LiNi") 0.5 Co 0.2 Mn 0.3 O2(NCM523 (may be abbreviated as "LiNi") 0.5 Co 0.25 Mn 0.25 O2(NCM 211 (may be abbreviated as "LiNi") 0.6 Co 0.2 Mn 0.2 O2(NCM 622 (may be abbreviated as "LiNi") 0.8 Co 0.1 Mn 0.1 O2(NCM 811 ), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.85 Co 0.15 Al 0.05 O2) and modifying compounds thereof, and the like.

[0051] 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.

[0052] In some examples, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0053] For example, the negative electrode current collector can be a metal foil sheet, a metal foam, or a composite current collector. For example, the metal foil sheet can be made of 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 polymeric base layer and a metal layer. The composite current collector can be formed by providing a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) on a polymeric substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, or polyethylene).

[0054] 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.

[0055] For example, the negative electrode current collector has two surfaces that face each other in the thickness direction of the negative electrode current collector, and the negative electrode active material is disposed on one or both of the two facing surfaces of the negative electrode current collector.

[0056] For example, the negative electrode active material may be any negative electrode active material for battery cells well 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, and lithium titanate. 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 that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination.

[0057] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0058] In some embodiments, the separator is a separator membrane, which can be selected from any well-known separator membrane with a porous structure that has excellent chemical and mechanical stability.

[0059] For example, the separator may be made of at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be located between the positive electrode and the negative electrode as a separate component, or may be attached to the surfaces of the positive electrode and the negative electrode.

[0060] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive and negative electrodes and simultaneously serves the dual roles of transporting ions and isolating the positive and negative electrodes.

[0061] In some embodiments, the battery cell further includes an electrolyte, which serves as ionic conductor between the positive electrode and the negative electrode. The electrolyte may be in a liquid, gel, or solid state. Here, the liquid electrolyte includes an electrolyte salt and a solvent.

[0062] In some embodiments, the electrolyte salt may include 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.

[0063] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl 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.

[0064] Here, the gel electrolyte comprises a polymer-based electrolyte skeletal network combined with an ionic liquid-lithium salt.

[0065] Here, the solid electrolyte includes polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0066] By way of example, the polymer solid electrolyte may be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single ion polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0067] By way of example, the inorganic solid electrolyte may include one or more of oxide solid electrolytes (crystalline perovskites, sodium superionic conductors, garnets, amorphous LiPON thin films), sulfide solid electrolytes (crystalline lithium superionic conductors (lithium germanium phosphate sulfur, sulfur silver germanite), amorphous sulfides), and halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0068] For example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0069] In some embodiments, the electrode assembly is a wound structure, in which the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0070] In some embodiments, the electrode assembly is a laminate structure.

[0071] 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 provided by alternately stacking them.

[0072] For example, multiple positive electrode sheets may be installed, and the negative electrode sheet may be folded to form multiple folded segments that are stacked and installed, with one positive electrode sheet sandwiched between adjacent folded segments.

[0073] By way of example, both the positive and negative electrode sheets are folded to form a plurality of folded segments that are placed in a stack.

[0074] For example, a plurality of separators may be provided, and each may be provided between any adjacent positive electrode sheets or negative electrode sheets.

[0075] For example, the separator may be disposed continuously, or may be disposed by folding or winding between any adjacent positive or negative electrode sheets.

[0076] In some embodiments, the electrode assembly may have a cylindrical, flat, or polygonal prism shape.

[0077] In some embodiments, the electrode assembly is provided with tabs that allow current to be conducted from the electrode assembly, including a positive electrode tab and a negative electrode tab.

[0078] In some embodiments, the battery cell may include a housing for packaging components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0079] For example, the battery cells may be cylindrical battery cells, prismatic battery cells, soft-pack battery cells, or battery cells of other shapes. Prismatic battery cells include square-cased battery cells, blade-shaped battery cells, and polygonal prism battery cells. Polygonal prism battery cells, such as hexagonal prism battery cells, are not particularly limited in this application.

[0080] The battery 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.

[0081] In some embodiments, the battery may be a battery module, and when there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0082] 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.

[0083] In some embodiments, the housing may be used as 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 transverse and longitudinal beams of the vehicle.

[0084] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage electrical cabinet, or the like.

[0085] In the case of a battery cell, the battery cell may include a housing, an electrode assembly, and an electrode terminal. The electrode assembly is accommodated in the housing, and the electrode terminal is attached to a wall of the housing. The electrode assembly includes an active material application portion and a tab attached to an end of the active material application portion, and the tab is electrically connected to the electrode terminal to input or output electrical energy via the electrode terminal.

[0086] To improve the current-carrying capacity of a battery cell, the tab of the electrode assembly of the battery cell may be directly connected to the electrode terminal, and the tab may be connected to the central region of the electrode terminal. To achieve effective connection between the electrode tab and the electrode terminal, the tab needs to be bent and installed between the active material coating portion and the electrode terminal. To meet the high-capacity requirements of a battery cell, the size of the battery cell may be increased. As the size of the battery cell increases, the width of the wall portion of the housing on which the electrode terminal is installed also increases. For example, if the electrode terminal is installed on an end cover, as the width of the end cover increases, the length of the portion of the end cover used to connect the tab to the electrode terminal also increases, resulting in an overall length of the tab. Tabs that are too long are prone to misalignment and wrinkling during the manufacturing process, resulting in reduced reliability of the battery cell.

[0087] In view of this, an embodiment of the present application provides a battery cell, in which the electrode terminal includes a terminal body and a limiting portion, the limiting portion includes a first extension portion protruding from the outer peripheral surface of the terminal body along a first direction, the tab includes a first connection portion and a second connection portion, the second connection portion is located on the side of the first connection portion along the first direction, the first connection portion is connected to the active material application portion, and the second connection portion is connected to the first extension portion.

[0088] In this battery cell, the second connection portion is located on the side of the first connection portion along the first direction, and the second connection portion is connected to the first extension portion that protrudes from the outer peripheral surface of the terminal body along the first direction of the limiting portion. This shortens the length of the second connection portion, thereby shortening the length of the tab, reducing the possibility of tab misalignment and wrinkles during manufacturing, and improving the reliability of the battery cell.

[0089] The technical solutions described in the embodiments of the present application are applied to batteries and power-consuming devices that use batteries.

[0090] The power consuming devices may be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools. The vehicles may be fuel oil vehicles, gas vehicles, or new energy vehicles, and the new energy vehicles may be pure electric vehicles, hybrid vehicles, or range-extended vehicles. The spacecraft include airplanes, rockets, space shuttles, and spaceships. The electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat toys, and electric airplane toys. The power tools include metal cutting power tools, polishing power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, hammer drills, concrete vibrators, and electric planers. The embodiments of the present application do not particularly limit the above power consuming devices.

[0091] For ease of explanation, the following embodiment will be described using a vehicle as an example of a power consuming device.

[0092] Referring to Fig. 1, Fig. 1 is a structural schematic diagram of a vehicle 1000 according to some embodiments of the present application. A battery 100 is installed inside the vehicle 1000, and the battery 100 may be installed at the bottom, front, or rear of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 can function as an operating power source for the vehicle 1000.

[0093] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300 for, for example, starting, navigation, and operating power consumption needs of the vehicle 1000.

[0094] In some embodiments of the present application, the battery 100 can provide not only the operating power source for the vehicle 1000, but also the driving power for the vehicle 1000, in place of, or in place of, fuel oil or natural gas.

[0095] 2, which is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a battery cell 10 and a housing 20, and the battery cell 10 is housed within the housing 20.

[0096] Here, the housing 20 is a member that houses the battery cells 10 and provides an accommodation space for the battery cells 10. The housing 20 can have various structures. In some embodiments, the housing 20 may include a first portion 201 and a second portion 202, which cover each other to define an accommodation space for accommodating the battery cells 10. The first portion 201 and the second portion 202 may have various shapes, such as a rectangular parallelepiped or a cylindrical shape. The first portion 201 may have a hollow structure with one side open, and the second portion 202 may also have a hollow structure with one side open. The open side of the second portion 202 is covered by the open side of the first portion 201, thereby forming the housing 20 having an accommodation space. In addition, the first part 201 may be a hollow structure with one side open, and the second part 202 may be a plate-like structure, and the second part 202 may be covered by the open side of the first part 201 to form a housing 20 having an accommodation space.

[0097] The battery 100 may have one or more battery cells 10. When there are multiple battery cells 10, the multiple battery cells 10 may be connected in series, parallel, or series-parallel. A series-parallel connection means that the multiple battery cells 10 are connected in both series and parallel. First, multiple battery cells 10 may be connected in series, parallel, or series-parallel to form a battery module, and then the multiple battery modules may be connected in series, parallel, or series-parallel to form an entire battery module, which is then housed in the housing 20. Alternatively, all of the battery cells 10 may be directly connected in series, parallel, or series-parallel, and then the entire battery module made up of all of the battery cells 10 may be housed in the housing 20.

[0098] In some embodiments, the battery 100 may further include a bus member, and the plurality of battery cells 10 may be electrically connected via the bus member to achieve a series connection, a parallel connection, or a series-parallel connection of the plurality of battery cells 10. The bus member may be a metallic conductor such as copper, iron, aluminum, stainless steel, or an aluminum alloy.

[0099] 3, which is an exploded view of a battery cell 10 according to some embodiments of the present application. The battery cell 10 may include a housing 1, an electrode assembly 2, and an electrode terminal 3, where the electrode assembly 2 is accommodated in the housing 1, the electrode terminal 3 is installed in the housing 1, and the electrode terminal 3 is electrically connected to the electrode assembly 2.

[0100] The housing 1 is a member for accommodating the electrode assembly 2, the electrolyte, etc. For example, the housing 1 may include a case 11 and an end cover 12.

[0101] Case 11 may have a hollow structure with an opening at one end, or may have a hollow structure with openings at both opposing ends. Case 11 may have various shapes such as a cylindrical shape or a rectangular pillar shape. Case 11 may be made of a single or multiple materials such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc.

[0102] The end cover 12 is a member that seals the opening of the case 11 and isolates the internal environment of the battery cell 10 from the external environment. The end cover 12 and the case 11 together define an accommodation space for accommodating the electrode assembly 2, the electrolyte, and other components. The shape of the end cover 12 may match the shape of the housing 1. For example, if the case 11 has a rectangular parallelepiped structure, the end cover 12 has a rectangular plate-like structure that fits the housing 1. For example, if the case 11 has a cylindrical structure, the end cover 12 has a circular plate-like structure that fits the case 11. The end cover 12 may be made of one or more materials such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc. The end cover 12 and the case 11 may be made of the same or different materials.

[0103] In an embodiment in which the case 11 is a hollow structure with an opening formed at one end, one end cover 12 may be provided correspondingly. In an embodiment in which the case 11 is a hollow structure with openings formed at opposite ends, two end covers 12 may be provided correspondingly, with the two end covers 12 sealing the two openings of the case 11, respectively, and the two end covers 12 and the case 11 defining an accommodation space.

[0104] The electrode terminal 3 is a member for inputting or outputting electrical energy in the battery cell 10. The electrode terminal 3 is installed in the housing 1 and is used for electrical connection with the tab 22 of the electrode assembly 2. The electrode terminal 3 may be installed in the case 11 of the housing 1 or in the end cover 12 of the housing 1. The electrode terminal 3 and the tab 22 may be directly connected; for example, the electrode terminal 3 and the tab 22 are directly welded together.

[0105] For example, as shown in Fig. 3, the case 11 has a hollow structure with openings formed at both opposing ends. End covers 12 are provided at both opposing ends of the case 11, and electrode terminals 3 are provided on the end covers 12 at both ends of the case 11. Tabs 22 are formed at both opposing ends of the electrode assembly 2, and the tab 22 at one end of the electrode assembly 2 is a positive electrode tab, and the tab 22 at the other end of the electrode assembly 2 is a negative electrode tab. The electrode terminal 3 on one end cover 12 is electrically connected to the positive electrode tab, and the electrode terminal 3 on the other end cover 12 is electrically connected to the negative electrode tab.

[0106] In some embodiments, the battery cell 10 may further include a third insulating member 4. The third insulating member 4 is disposed between the electrode assembly 2 and the case 11 and is used to insulate and separate the electrode assembly 2 from the case 11. The third insulating member 4 is made of an insulating material such as plastic or rubber. For example, the third insulating member 4 is an insulating film coated around the electrode assembly 2.

[0107] 4 and 5, FIG. 4 is a partial view of a battery cell 10 according to some embodiments of the present application, and FIG. 5 is a partial enlarged view of portion A in FIG. 4. The embodiments of the present application provide a battery cell 10 including a housing 1, an electrode assembly 2, and an electrode terminal 3. The housing 1 includes a wall 13, and the wall 13 has an outlet hole 131. The electrode assembly 2 is accommodated within the housing 1 and includes an active material application portion 21 and a tab 22. The tab 22 is installed on the end of the active material application portion 21 facing the wall 13. The electrode terminal 3 includes a terminal body 31 and a limiting portion 32. The terminal body 31 is inserted into the outlet hole 131. The limiting portion 32 is configured to limit the terminal body 31 from being removed from the outlet hole 131 in a direction away from the active material application portion 21. The limiting portion 32 includes a first extension portion 321 protruding from an outer circumferential surface 311 of the terminal body 31 along a first direction X. The tab 22 includes a first connection portion 221 and a second connection portion 222, the second connection portion 222 being located on the side of the first connection portion 221 along the first direction X, the first connection portion 221 being connected to the active material application portion 21, and the second connection portion 222 being connected to the first extension portion 321.

[0108] It can be understood that the wall 13 may be an end cover 12 of the housing 1, and that the electrode terminal 3 is installed on the end cover 12. It can also be understood that the wall 13 may be one wall of the case 11 of the housing 1, and that the electrode terminal 3 is installed on the case 11. The wall 13 may be a circular wall, a rectangular wall, or the like.

[0109] The pull-out hole 131 in the wall 13 is for pulling out the terminal body 31 of the electrode terminal 3, which facilitates connection of the terminal body 31 to an external member of the battery cell 10, for example, connection of the terminal body 31 to a bus member. The pull-out hole 131 penetrates the wall 13 along the thickness direction of the wall 13 and may be a rectangular hole, a circular hole, or the like.

[0110] The electrode assembly 2 may include a positive electrode sheet, a negative electrode sheet, and a separator. The electrode assembly 2 may have a wound structure formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, or a laminated structure formed by stacking a positive electrode sheet, a separator, and a negative electrode sheet. The active material application section 21 is a main body portion of the electrode assembly 2. The active material application section 21 may be a portion of the electrode assembly 2 corresponding to a region where an active material layer is applied to the electrode sheet, and the tab 22 may be a portion of the electrode sheet where an active material layer is not applied.

[0111] The first connecting portion 221 is a portion of the tab 22 for connecting to the active material-coated portion 21, and the second connecting portion 222 is a portion of the tab 22 for connecting to the electrode terminal 3. The first connecting portion 221 may have a linear sheet structure or an arc-shaped sheet structure. The second connecting portion 222 may have a linear sheet structure or an arc-shaped sheet structure. In the embodiment shown in FIG. 4, both the first connecting portion 221 and the second connecting portion 222 have a linear sheet structure. For example, the tab 22 is bent between the electrode terminal 3 and the active material-coated portion 21. The tab 22 is bent to form a plurality of connected bent segments. The first connecting portion 221 and the second connecting portion 222 are two bent segments at both ends of the tab 22.

[0112] The first connection portion 221 may be directly or indirectly connected to the active material application portion 21. For example, the first connection portion 221 is connected to the active material application portion 21 via a tab root portion 223.

[0113] The first direction X is a direction in which the first extending portion 321 protrudes from the outer peripheral surface 311 of the terminal body 31. The first direction X is set to one direction. The first direction X may be perpendicular to the axial direction Z of the terminal body 31. For example, if the wall portion 13 is a rectangular parallelepiped wall portion, the first direction X may be parallel to the longitudinal direction of the wall portion 13, or the first direction X may be parallel to the width direction of the wall portion 13.

[0114] The second connection portion 222 is located on the side of the first connection portion 221 along the first direction X. For example, if the first direction X is the direction from the left side to the right side of the electrode terminal 3, the second connection portion 222 is located on the right side of the first connection portion 221.

[0115] The electrode terminal 3 is a metal conductor. The electrode terminal 3 may be made entirely of the same conductive material, such as copper, iron, aluminum, steel, or an aluminum alloy. The electrode terminal 3 may also be formed by combining multiple parts made of different conductive materials; for example, the terminal body 31 may be formed by combining two parts made of copper and aluminum.

[0116] The terminal body 31 is a portion that is drilled into the drawing hole 131. The terminal body 31 has a cylindrical shape and may be cylindrical, rectangular, or prismatic. The limiting portion 32 is a portion that restricts the terminal body 31 of the electrode terminal 3 from being removed from the drawing hole 131 in a direction away from the active material-coated portion 21. The limiting portion 32 may be a plate-shaped member such as a rectangular plate or a circular plate. The limiting portion 32 may be connected to an end of the terminal body 31 that faces the electrode assembly 2. For example, the limiting portion 32 is located inside the wall portion 13. That is, the limiting portion 32 is located on the side of the wall portion 13 that faces the active material-coated portion 21. Since the orthogonal projections of the limiting portion 32 and the wall portion 13 on a plane perpendicular to the axial direction Z of the terminal body 31 at least partially overlap, the limiting portion 32 can effectively restrict the terminal body 31 from being removed from the drawing hole 131 in a direction away from the active material-coated portion 21.

[0117] The battery cell 10 may further include a connection member 5, which is located on the side of the wall 13 away from the active material application portion 21 and is connected to the terminal body 31. The connection member 5 is configured to restrict movement of the terminal body 31 in a direction toward the electrode assembly 2 and, together with the restricting portion 32, fix the electrode terminal 3 to the wall 13. For example, the connection member 5 is riveted to the terminal body 31. The connection member 5 may be used to connect to an external member to increase the current passing area of ​​the electrode terminal 3. A fourth insulating member 6 may be disposed between the connection member 5 and the wall 13 to achieve insulation between the connection member 5 and the wall 13. A sealing member 7 may be disposed between the terminal body 31 and the wall 13 to improve sealing between the terminal body 31 and the wall 13, with at least a portion of the sealing member 7 located within the drawing hole 131.

[0118] The first extension portion 321 is a portion of the limiting portion 32 that protrudes from the outer peripheral surface 311 of the terminal body 31 along the first direction. The outer peripheral surface 311 of the terminal body 31 is disposed around the axis of the terminal body 31. See FIGS. 6 and 7. FIG. 6 is an axonometric view of the electrode terminal 3 shown in FIG. 4, and FIG. 7 is an axonometric view of the electrode terminal 3 shown in FIG. 6. For example, assuming that the outer peripheral surface 311 of the terminal body 31 is a cylindrical surface, the first cross section 322 that contacts the outer peripheral surface 311 of the limiting portion 32 is the starting position of the first extension portion 321. The first cross section 322 is perpendicular to the first direction X, and the first extension portion 321 extends from this starting position along the first direction X. The first extension portion 321 and the second connection portion 222 may be connected in various ways, such as by welding or adhesive, to achieve electrical connection between the electrode terminal 3 and the tab 22.

[0119] In the related art, the tab 22 is generally connected to a central region of the electrode terminal 3, which is the central region of the terminal body 31. This makes the electrode tab 22 too long, making the tab 22 prone to misalignment and wrinkling during the manufacturing process. This results in reduced reliability of the battery cell 10. In the embodiment of the present application, the second connection portion 222 is located on the side of the first connection portion 221 along the first direction X. The second connection portion 222 is connected to the first extension portion 321 of the limiting portion 32, which protrudes from the outer peripheral surface 311 of the terminal body 31 along the first direction X. This shortens the length of the second connection portion 222, thereby shortening the length of the tab 22. This reduces the likelihood of the tab 22 being misaligned and wrinkling during the manufacturing process, improving the reliability of the battery cell 10.

[0120] In some embodiments, reference is made to FIGS. 8 and 9 . FIG. 8 is a partial view of a battery cell 10 according to some other embodiments of the present application, and FIG. 9 is a structural schematic diagram of the electrode terminal 3 shown in FIG. 8 . The limiting portion 32 further includes a second extending portion 323 protruding from the outer circumferential surface 311 of the terminal body 31 in a direction opposite to the first direction X. In the direction along the first direction X, the distance between the end of the second extending portion 323 remote from the terminal body 31 and the central axis 312 of the terminal body 31 is a first distance L1. The first extending portion 321 includes an extending region 3211, and the distance between the extending region 3211 and the central axis 312 is equal to or greater than the first distance L1. The second connecting portion 222 is connected to the extending region 3211.

[0121] The second extension portion 323 is a portion of the limiting portion 32 that protrudes from the outer peripheral surface 311 of the terminal body 31 in the direction opposite to the first direction X. The extending direction of the second extension portion 323 is opposite to that of the first extension portion. For example, if the first X direction is the direction from the left side to the right side of the electrode terminal 3, the first extension portion 321 extends from left to right from the outer peripheral surface 311 of the terminal body 31, and the second extension portion 323 extends from right to left from the outer peripheral surface 311 of the terminal body 31. For example, if the outer peripheral surface 311 of the terminal body 31 is a cylindrical surface, the second cross section 324 that contacts the outer peripheral surface 311 of the limiting portion 32 is the starting position of the second extension portion 323. The second cross section 324 is perpendicular to the first direction X, and the second cross section 324 and the first cross section 322 are located on either side of the terminal body 31 along the first direction X, and the second extension portion 323 extends from this starting position in the opposite direction to the first direction X.

[0122] The extension region 3211 may be a region of the first extension portion 321 other than the first distance L1 from the central axis 312. The first extension portion 321 further includes a connection region 3212, which is located between the terminal body 31 and the extension region 3211 in the first direction X and connects the terminal body 31 and the extension region 3211. For example, the length of the connection region 3212 in the first direction X is equal to the length of the second extension portion 323. In the first direction X, the length of the first extension portion 321 is longer than the length of the second extension portion 323, and the difference between the lengths of the first extension portion 321 and the second extension portion 323 is equal to the length of the extension region 3211.

[0123] The restricting portion 32 has a third cross section 235 perpendicular to the first direction X, and in the direction along the first direction X, the distance between the third cross section 235 and the central axis 312 of the terminal body 31 is a first distance L1, and the third cross section 235 can function as a starting position of the extension region 3211, and the extension region 3211 extends along the first direction X from this starting position.

[0124] The first distance L1 may be measured using a vernier. Specifically, first, the position of the central axis 312 of the terminal body 31 is determined on one end face of the terminal body 31 in the axial direction Z, and a marking point is attached thereto. Next, in an environment of 25±2°C, the distance along the first direction X between the end of the second extension portion 323 remote from the terminal body 31 and the marking point is measured using a vernier. This distance is the first distance L1.

[0125] In this embodiment, by providing the extension region 3211, the length of the first extension portion 321 in the second direction Y is increased, and the second extension portion 323 is increased in the direction away from the terminal body 31. As a result, since the second connection portion 222 is connected to the extension region 3211, the second connection portion 222 is further away from the terminal body 31 in the first direction X, and thus the second connection portion 222 can be made shorter, which is advantageous for further shortening the length of the tab 22.

[0126] In some embodiments, still referring to FIG. 9 , along the first direction X, the distance between the end of the second connecting portion 222 closer to the terminal body 31 and the central axis 312 of the terminal body 31 is a second distance L2, and the second distance L2 is greater than or equal to the first distance L1.

[0127] L2 may be greater than L1, or L2 may be equal to L1. This prevents the orthogonal projections of the second connecting portion 222 and the connecting region 3212 from overlapping on a plane perpendicular to the axial direction Z of the terminal body 31. It can be seen that the greater the difference between L2 and L1, the farther the second connecting portion 222 is from the central axis 312 of the terminal body 31.

[0128] The second distance L2 may also be measured using a vernier. Specifically, first, the position of the central axis 312 of the terminal body 31 is determined on one end face of the terminal body 31 in the axial direction Z, and a marking point is attached thereto. Next, in an environment of 25±2°C, the distance along the first direction X between the end of the second extension portion 323 remote from the terminal body 31 and the marking point is measured using a vernier. This distance is the first distance L1.

[0129] In this embodiment, L2≧L1, so that the end of the second connecting portion 222 closer to the terminal body 31 is further away from the terminal body 31 along the first direction X, further shortening the length of the second connecting portion 222, and thereby further shortening the length of the tab 22.

[0130] In some embodiments, still referring to FIG. 8 , the first connection portion 221 faces an intermediate position along the first direction X of the active material application portion 21, and / or the terminal body 31 faces an intermediate position along the first direction X of the active material application portion 21.

[0131] The first connection portion 221 faces the middle position of the active material applied portion 21 in the first direction X. That is, the distances from the first connection portion 221 to both ends of the active material applied portion 21 in the first direction X are substantially equal.

[0132] The terminal body 31 faces the active material coated part 21 at a midpoint in the first direction X. That is, the distances from the central axis 312 of the terminal body 31 to both ends of the active material coated part 21 in the first direction X are substantially equal.

[0133] When the first connection portion 221 faces the intermediate position of the active material application portion 21 in the first direction X, the tab 22 is positioned at the center in the first direction X before being bent, which is advantageous for forming the tab 22 and reduces the difficulty of forming the tab 22. When the terminal body 31 faces the intermediate position of the active material application portion 21 in the first direction X, the terminal body 31 is positioned at the center in the first direction X, which is advantageous for connecting the electrode terminal 3 to an external member (such as a bus member) and makes it easier to output or input electrical energy.

[0134] In some embodiments, still referring to FIG. 8, the tab 22 further includes a third connection portion 224 and a fourth connection portion 225, and the first connection portion 221, the third connection portion 224, the fourth connection portion 225 and the second connection portion 222 are connected in sequence, and the second connection portion 222 and the third connection portion 224 are arranged opposite each other in the direction along the axial direction Z of the terminal body 31.

[0135] The third connecting portion 224 may have a linear or arcuate sheet structure, and the fourth connecting portion 225 may have a linear or arcuate sheet structure. The third connecting portion 224 is bent relative to the first connecting portion 221, the fourth connecting portion 225 is bent relative to the third connecting portion 224, and the second connecting portion 222 is bent relative to the fourth connecting portion 225. The third connecting portion 224 and the first connecting portion 221 may be disposed at an acute angle, an obtuse angle, or a right angle, the fourth connecting portion 225 and the third connecting portion 224 may be disposed at an acute angle, an obtuse angle, or a right angle, and the second connecting portion 222 and the fourth connecting portion 225 may be disposed at an acute angle, an obtuse angle, or a right angle. In the embodiment shown in Figure 8, the first connection portion 221, the second connection portion 222, the third connection portion 224 and the fourth connection portion 225 are all linear sheet structures, and the third connection portion 224 and the first connection portion 221 are installed at a right angle, the fourth connection portion 225 and the third connection portion 224 are installed at a right angle, and the second connection portion 222 and the fourth connection portion 225 are installed at a right angle.

[0136] The second connecting portion 222 and the third connecting portion 224 are disposed opposite each other along the axial direction Z of the terminal body 31. That is, the orthogonal projections of the second connecting portion 222 and the third connecting portion 224 on a plane perpendicular to the axial direction Z of the terminal body 31 at least partially overlap.

[0137] In this embodiment, since the tab 22 is bent between the active material application portion 21 and the electrode terminal 3, the internal space of the battery cell 10 occupied by the tab 22 is reduced, and more space is provided for the active material application portion 21, which is advantageous for improving the energy density of the battery cell 10.

[0138] In some embodiments, still referring to FIG. 9, along the axial direction Z of the terminal body 31, the second connection portion 222 is connected to the side of the first extension portion 321 facing the active material applied portion 21.

[0139] For example, in the direction along the axial direction Z of the terminal body 31, the first extending portion 321 has a first surface 3213 and a second surface 3214 that face each other. The first surface 3213 faces the active material applied portion 21, the second surface 3214 is away from the active material applied portion 21, and the second connecting portion 222 is connected to the first surface 3213.

[0140] In this embodiment, since the second connection portion 222 is connected to the side of the first extension portion 321 facing the active material application portion 21, the distance between the second connection portion 222 and the active material application portion 21 in the axial direction Z of the terminal body 31 is shortened, and the length of the tab 22 can be effectively shortened.

[0141] In some other embodiments, the second connection portion 222 may be connected to another position of the first extension portion 321, for example, in the direction along the axial direction Z of the terminal body 31, the second connection portion 222 is connected to the side of the first extension portion 321 away from the active material application portion 21.

[0142] 9 , in some embodiments, the terminal body 31 and the limiting portion 32 are integrally molded. This increases the connection strength between the terminal body 31 and the limiting portion 32, making the terminal body 31 and the limiting portion 32 more rigid. This reduces the possibility that the terminal body 31 will separate from the limiting portion 32 due to an impact force during normal use of the battery cell 10, thereby reducing the possibility of failure of the battery cell 10 during normal use.

[0143] In some other embodiments, the terminal body 31 and the limiting portion 32 may be installed separately and then connected. For example, the terminal body 31 and the limiting portion 32 may be made of different materials, one of the terminal body 31 and the limiting portion 32 may be made of copper and the other of aluminum, and the terminal body 31 and the limiting portion 32 may be combined.

[0144] In some embodiments, refer to Figure 10. Figure 10 is a partial enlarged view of portion B in Figure 8. The battery cell 10 further includes a first insulating member 8. In the direction along the axial direction Z of the terminal body 31, the first insulating member 8 includes a first insulating portion 81 disposed between the first extending portion 321 and the wall portion 13, and a heat insulating structure is disposed on the side of the first insulating portion 81 facing the first extending portion 321 and / or the side of the first extending portion 321 facing the first insulating portion 81.

[0145] The first insulating member 8 is installed on the side of the wall portion 13 facing the active material application portion 21, and separates the limiting portion 32 from the wall portion 13, thereby achieving electrical isolation between the wall portion 13 and the limiting portion 32. The first insulating member 8 is made of an insulating material such as plastic or rubber. The first insulating portion 81 is a portion located between the first extending portion 321 of the first insulating member 8 and the wall portion 13.

[0146] The heat insulating structure may be provided only on the side of the first insulating portion 81 facing the first extending portion 321, or may be provided only on the side of the first extending portion 321 facing the first insulating portion 81, or may be provided on both the side of the first insulating portion 81 facing the first extending portion 321 and the side of the first extending portion 321 facing the first insulating portion 81. The heat insulating structure may be various structures such as a groove, a heat insulating member, or the like.

[0147] The insulating structure serves the role of insulation, delaying or preventing heat transfer between the first extension portion 321 and the first insulating portion 81, reducing the possibility of melting of the first insulating portion 81 due to heat transfer from the first extension portion 321 to the first insulating portion 81, and reducing the possibility of poor insulation of the first insulating portion 81.

[0148] In some embodiments, continue to refer to Figures 10 and 11. Figure 11 is an axonometric view of the electrode terminal 3 shown in Figure 10. The heat insulating structure includes a relief groove 3215 provided in the first insulating portion 81 and / or the first extending portion 321.

[0149] As can be understood, the escape groove 3215 may be provided only in the first insulating portion 81, or the escape groove 3215 may be provided only in the first extending portion 321, or the escape groove 3215 may be provided in both the first insulating portion 81 and the first extending portion 321.

[0150] For example, in the case where the escape groove 3215 is provided in the first extending portion 321, the surface of the first extending portion 321 facing the first insulating portion 81 along the axial direction Z of the terminal body 31 is the second surface 3214, and the escape groove 3215 is provided in the second surface 3214 of the first extending portion 321. In an embodiment in which the first extending portion 321 has the extension region 3211, the escape groove 3215 may be provided in the extension region 3211.

[0151] In this embodiment, the heat insulating structure is simple and easy to mold. By providing the clearance groove 3215, the first extending portion 321 and the first insulating portion 81 are less likely to come into direct contact with each other in the area corresponding to the clearance groove 3215, and an excellent heat insulating effect is achieved.

[0152] In some other embodiments, an escape groove 3215 may be provided in the first insulating portion 81 and / or the first extending portion 321, and then a heat insulating member may be provided in the first insulating portion 81 and / or the first extending portion 321.

[0153] In some embodiments, still referring to FIG. 10, the second connection portion 222 is welded to the first extension portion 321 to form a weld mark area 3216, and the orthogonal projection of the weld mark area 3216 and the relief groove 3215 in a plane perpendicular to the axial direction of the terminal body 31 at least partially overlaps.

[0154] The second connection portion 222 is welded to the first extension portion 321, and the weld mark region 3216 is a weld mark portion formed by welding the second connection portion 222 and the first extension portion 321. It can be seen that at least a portion of the weld mark region 3216 projected along the axial direction Z of the terminal body 31 is located within the relief groove 3215.

[0155] When the second connection portion 222 is welded to the first extension portion 321, a large amount of heat is generated in the weld mark region 3216 of the first extension portion 321, causing the temperature of the first extension portion 321 to rise. Because the orthogonal projections of the weld mark region 3216 and the relief groove 3215 on a plane perpendicular to the axial direction Z of the terminal body 31 at least partially overlap, the relief groove 3215 can provide excellent heat insulation and reduce the impact of the first extension portion 321 and the second connection portion 222 on the first insulating portion 81 during the welding process.

[0156] In some embodiments, the area of ​​the orthogonal projection of the weld mark region 3216 on a plane perpendicular to the axial direction Z of the terminal body 31 is S1, and the area of ​​overlap of the orthogonal projection of the weld mark region 3216 and the relief groove 3215 on a plane perpendicular to the axial direction Z of the terminal body 31 is S2, satisfying S2 / S1≧1 / 3.

[0157] S2 / S1 may be any one of the point values ​​1 / 3, 1 / 2, 2 / 3, 1 or a range value between any two of them.

[0158] Taking the example of a case where the weld mark region 3216 and the relief groove 3215 are formed on two opposing surfaces of the first extension portion 321, the specific method for measuring S2 and S1 is as follows: The electrode terminal 3 is clamped with the weld mark region 3216 facing upward, and the area of ​​the region defined by the outline of the weld mark region 3216 is measured with a CCD camera positioned directly above the electrode terminal 3, and this area is designated as S1. The electrode terminal 3 is inverted using an inversion mechanism within the clamp, and the electrode terminal 3 is rotated 180 degrees around an axis extending along the first direction X. At this time, the relief groove 3215 faces upward. Next, the area of ​​the overlapping region between the region defined by the outline of the relief groove 3215 and the region defined by the outline of the weld mark region 3216 is measured with the CCD camera, and this overlapping region is designated as S2.

[0159] In this embodiment, S2 / S1≧1 / 3, and the area of ​​the overlapping region of the orthogonal projection of the weld mark region 3216 on a plane and the relief groove 3215 accounts for a large proportion of the area of ​​the orthogonal projection of the weld mark region 3216 on a plane, so that more of the heat generated in the weld mark region 3216 of the first extension portion 321 during the welding process can be blocked by the relief groove 3215. This improves the blocking ability of the relief groove 3215 against the heat of the weld mark region 3216.

[0160] In some embodiments, S2 / S1≧½.

[0161] In the embodiment shown in FIG. 10, S2 / S1=1, so that the projection of the weld mark region 3216 along the axial direction Z of the terminal body 31 is located entirely within the relief groove 3215.

[0162] In this embodiment, S2 / S1≧1 / 2, and the ratio of S2 in S1 is further increased, which further improves the insulating ability of the relief groove 3215 against the heat of the weld mark region 3216.

[0163] In some embodiments, refer to Fig. 12. Fig. 12 is an axonometric view of an electrode terminal 3 according to some other embodiments of the present application. A fusion portion 3217 is formed in the first extension portion 321.

[0164] The fusing portion 3217 is a portion of the first extension portion 321 that can be fused when an overcurrent occurs, and the resistance of the fusing portion 3217 is greater than the resistance of other portions of the first extension portion 321. There may be one or more fusing portions 3217 on the first extension portion 321. The fusing portion 3217 may be formed by correspondingly providing a hole or a groove in the first extension portion 321. In an embodiment in which the first extension portion 321 includes the connection region 3212 and the extension region 3211, the fusing portion 3217 may be located in the connection region 3212, or the fusing portion 3217 may be located in the extension region 3211, or a portion of the fusing portion 3217 may be located in the connection region 3212 and the other portion may be located in the extension region 3211.

[0165] In this embodiment, a fusing portion 3217 is formed in the first extension portion 321, and when the current passing through the first extension portion 321 is too large, the fusing portion 3217 automatically fuses to provide overcurrent protection for the battery cell 10.

[0166] In some embodiments, still referring to FIG. 12 , a through hole 3218 is provided in the first extension portion 321, and both ends of the through hole 3218 extend to two opposite surfaces of the first extension portion 321 along the axial direction Z of the terminal body 31, respectively, to form a corresponding fusing portion 3217.

[0167] The through hole 3218 on the first extension portion 321 may be one or more. The through hole 3218 may be a circular hole, a rectangular hole, or the like. The through hole 3218 may be a complete hole or an incomplete hole. When the through hole 3218 does not extend to the edge of the first extension portion 321 along a direction perpendicular to the axial direction Z of the terminal body 31, the through hole 3218 is a complete hole. When the through hole 3218 extends to the edge of the first extension portion 321 along a direction perpendicular to the axial direction Z of the terminal body 31, the through hole 3218 is an incomplete hole.

[0168] For example, the two surfaces of the first extension portion 321 arranged opposite to each other along the axial direction Z of the terminal body 31 are a first surface 3213 (not shown in Figure 12) and a second surface 3214 (not shown in Figure 12), respectively, the first surface 3213 faces the active material application portion 21 (not shown in Figure 12) and the second surface 3214 is away from the active material application portion 21, the first surface 3213 is used for connection with the second connection portion 222, and the escape groove 3215 is arranged on the second surface 3214.

[0169] In this embodiment, by providing through-hole 3218 in first extension 321, fusing portion 3217 is formed adjacent to the through-hole. This simplifies the method of forming fusing portion 3217. After providing through-hole 3218 in first extension 321, the cross-sectional area of ​​fusing portion 3217 formed is smaller than the cross-sectional area of ​​the rest of first extension 321. As a result, the resistance of fusing portion 3217 is greater than the resistance of the rest of first extension 321. If the current passing through first extension 321 is too large, fusing portion 3217 will generate heat and melt.

[0170] In some embodiments, the first extension portion 321 has a plurality of through holes 3218 arranged at intervals along the second direction Y, and the second direction Y intersects with the first direction X.

[0171] The number of through holes 3218 on the first extension portion 321 may be two, three, four, five, etc. In the direction along the second direction Y, one fusion portion 3217 is formed between two adjacent through holes 3218. For example, the second direction Y, the first direction X, and the axial direction Z of the terminal body 31 are perpendicular to each other.

[0172] When the current passing area of ​​the fusion portion 3217 is constant, by providing a plurality of through holes 3218 in the first extension portion 321, the through holes 3218 can be made smaller, and the difficulty in forming the through holes 3218 can be reduced.

[0173] In some embodiments, still referring to FIG. 12, two through holes 3218 are provided in the first extension portion 12, and in the direction along the second direction Y, the two through holes 3218 extend to both ends of the first extension portion 321, respectively, and the fusing portion 3217 is located between the two through holes 3218.

[0174] The two through holes 3218 extend to both ends of the first extension portion 321 along the second direction Y, and since the through holes 3218 are incomplete holes, the two through holes 3218 can be considered to be two notches located at both ends of the first extension portion 321 in the second direction Y.

[0175] In this embodiment, since only one fusing portion 3217 is formed in the first extension portion 321, it becomes easier to control the current passing area of ​​the fusing portion 3217, the structure of the electrode terminal 3 is simplified, and the difficulty of forming the electrode terminal 3 is reduced.

[0176] In some embodiments, refer to Figures 13 to 15. Figure 13 is an axonometric view of the electrode terminal 3 and the second insulating member 9 according to some embodiments of the present application after they have been connected, Figure 14 is a cross-sectional view of the electrode terminal 3 and the second insulating member 9 shown in Figure 13 after they have been connected, and Figure 15 is an axonometric view of the electrode terminal 3 and the second insulating member 9 according to some other embodiments of the present application after they have been connected. The battery cell 10 further includes a second insulating member 9, and the second insulating member 9 covers at least a portion of the outer surface of the fusing portion 3217.

[0177] The second insulating member 9 is made of an insulating material such as plastic, rubber, etc. The second insulating member 9 may cover a part of the outer surface of the fusing portion 3217, or may cover the entire outer surface of the fusing portion 3217.

[0178] 13 and 14, the second insulating member 9 is coated around the periphery of the fusing portion 3217 so that the second insulating member 9 covers the entire outer surface of the fusing portion 3217. In the embodiment shown in Fig. 15, the second insulating member 9 is coated around the periphery of the first extension portion 321, so that both the fusing portion 3217 and the through hole 3218 are located within the second insulating member 9 and are shielded by the second insulating member 9. The second insulating member 9 may also partially fill the through hole 3218.

[0179] In this embodiment, the second insulating member 9 plays an insulating role, and reduces the risk that the electrode terminal 3 will conduct electricity between the positive electrode sheet and the negative electrode sheet after the fusing portion 3217 has blown out.

[0180] In some embodiments, the second insulating member 9 comprises an insulating coating disposed on the outer surface of the fusing portion 3217, an insulating adhesive layer adhered to the outer surface of the fusing portion 3217, or a heat-sealed insulating layer heat-sealed to the outer surface of the fusing portion 3217.

[0181] In an embodiment in which the second insulating member 9 is an insulating coating provided on the outer surface of the fusing portion 3217, when an insulating coating is provided on the surface of the fusing portion 3217, an insulating coating may also be provided on the wall surface of the through hole 3218. The insulating coating is thin and occupies a small space.

[0182] In an embodiment in which second insulating member 9 is an insulating adhesive layer adhered to the outer surface of fusing portion 3217, the insulating adhesive layer may be coated around fusing portion 3217 or may be coated around first extending portion 321. In this case, both fusing portion 3217 and through hole 3218 are located within the insulating adhesive layer and are shielded by the insulating adhesive layer. The insulating adhesive layer may be adhered to fusing portion 3217. In this case, assembly efficiency can be increased and manufacturing costs can be reduced.

[0183] In an embodiment in which the second insulating member 9 is a heat-sealed insulating layer heat-sealed to the outer surface of the fusing portion 3217, the heat-sealed insulating layer may be coated around the fusing portion 3217 or the first extending portion 321. In this case, both the fusing portion 3217 and the through-hole 3218 are located within the heat-sealed insulating layer and are shielded by the heat-sealed insulating layer. The heat-sealed insulating layer may partially fill the through-hole 3218. The heat-sealed insulating layer is heat-sealed to the fusing portion 3217. After the fusing portion 3217 is blown, the heat-sealed insulating layer not only provides insulation but also acts as a limiting factor, maintaining the original shape of the electrode terminal 3 and reducing the possibility of contact between the electrode terminal 3 and the electrode sheet of the active material coating portion 21 after the fusing portion 3217 is blown, thereby reducing the possibility of a short circuit occurring inside the battery cell 10.

[0184] 16 to 18 are referenced in some embodiments. Fig. 16 is an axonometric view of the electrode terminal 3 and the second insulating member 9 according to some further embodiments of the present application after they have been connected, Fig. 17 is a cross-sectional view of the electrode terminal 3 and the second insulating member 9 shown in Fig. 16 after they have been connected, and Fig. 18 is a CC cross-sectional view of the electrode terminal 3 and the second insulating member 9 shown in Fig. 17 after they have been connected. The second insulating member 9 includes a second insulating member 91 and a third insulating member 92. The second insulating member 91 and the third insulating member 92 define a first space 93. The fusing portion 3217 is housed in the first space 93. The second insulating member 91 and the third insulating member 92 are detachably connected.

[0185] The second insulating part 91 and the third insulating part 92 are two parts installed separately from the second insulating member 9. The second insulating part 91 and the third insulating part 92 may be removably connected in various ways, such as by interlocking, interference fit, or locking member connection. The locking member may be a member such as a screw, a bolt, or a latch.

[0186] The first space 93 is an internal space of the second insulating member 9, and is defined by the second insulating portion 91 and the third insulating portion 92. A portion of the first space 93 can be located within the second insulating portion 91, and another portion can be located within the third insulating portion 92.

[0187] In this embodiment, the second insulating portion 91 and the third insulating portion 92 are detachably connected, which allows for easy attachment and detachment of the second insulating member 9. The second insulating member 9 having this structure not only provides insulation after the fusing portion 3217 is blown, but also serves as a restriction, maintaining the original shape of the electrode terminal 3 and reducing the possibility of contact between the electrode terminal 3 and the electrode sheet of the active material-coated portion 21 after the fusing portion 3217 is blown, thereby reducing the possibility of a short circuit occurring inside the battery cell 10.

[0188] In some embodiments, still referring to FIG. 18, the second insulating portion 91 has a first locking portion 911, and the third insulating portion 92 has a second locking portion 921, and the first locking portion 911 and the second locking portion 921 fit together.

[0189] 18, for example, the first locking portion 911 is a hook that protrudes from the surface of the second insulating portion 91 facing the third insulating portion 92. The second locking portion 921 is an engagement groove that engages with the hook, and the engagement groove is provided on the surface of the third insulating portion 92 facing the second insulating portion 91.

[0190] When attaching the second insulating member 9, the second insulating part 91 and the third insulating part 92 can be connected by fitting the first locking part 911 into the second locking part 921, and the second insulating part 91 and the third insulating part 92 can be separated by releasing the engagement between the first locking part 911 and the second locking part 921, making it easy to attach and detach the second insulating part 91 and the third insulating part 92.

[0191] In some other embodiments, the first locking portion 911 and the second locking portion 921 may have other structures, for example, the first locking portion 911 is a protrusion, the second locking portion 921 is an insertion hole, and the protrusion is inserted into the insertion hole to form a tight fit.

[0192] In some embodiments, the restriction 32 is provided with a weight reduction structure.

[0193] The weight reduction structure may be various structures, for example, holes, grooves, etc., provided in the restriction 32.

[0194] In this embodiment, the weight of the electrode terminal 3 can be reduced by providing a weight reduction structure, thereby reducing the weight of the battery cell 10 .

[0195] 19 is an axonometric view of an electrode terminal 3 according to some embodiments of the present application. The weight reduction structure includes a weight reduction hole 326 disposed in the limiting portion 32, and both ends of the weight reduction hole 326 extend to two surfaces of the limiting portion 32 that are oppositely disposed along the axial direction Z of the terminal body 31.

[0196] The weight-reducing hole 326 on the limiting portion 32 may be one or more. The weight-reducing hole 326 may be a circular hole, a rectangular hole, or the like. The weight-reducing hole 326 may be a complete hole or an incomplete hole. When the through hole 3218 does not extend to the edge of the limiting portion 32 along a direction perpendicular to the axial direction Z of the terminal body 31, the through hole 3218 is a complete hole. When the through hole 3218 extends to the edge of the limiting portion 32 along a direction perpendicular to the axial direction Z of the terminal body 31, the through hole 3218 is an incomplete hole.

[0197] In this embodiment, the weight of the electrode terminal 3 can be reduced by providing the weight reduction hole 326 in the limiting portion 32, which can be easily achieved.

[0198] In some embodiments, the weight reduction structure includes a plurality of weight reduction holes 326 , which are located around the periphery of the terminal body 31 .

[0199] The weight reduction holes 326 on the restriction 32 may be two, three, four, five, etc.

[0200] In this embodiment, the limiting portion 32 is provided with a plurality of weight-reducing holes 326, which can further reduce the weight of the electrode terminal 3.

[0201] In some embodiments, and with continued reference to FIG. 19, the four corners of the restriction 32 are provided with weight-reducing holes 326 .

[0202] For example, the limiting portion 32 is a rectangular plate, the weight-reducing hole 326 is an incomplete hole, and the weight-reducing hole 326 extends to one end in the longitudinal direction and one end in the width direction of the limiting portion 32.

[0203] In this embodiment, the weight-reducing holes 326 are provided at the four corners of the restricting portion 32, which further reduces the weight of the electrode terminal 3 and also reduces the influence on the passage of current through the electrode terminal 3.

[0204] In some embodiments, weight-reducing holes 326 are located in first extension 321 to form corresponding fuses 3217 .

[0205] In the embodiment shown in FIG. 12, the through-holes 3218 of the first extension portion 321 may function as weight-reducing holes 326 .

[0206] In this embodiment, by providing the weight-reducing hole 326 in the first extending portion 321, the fusing portion 3217 can be formed and the weight of the electrode terminal 3 can be reduced.

[0207] In some embodiments, the housing 1 includes a case 11 and an end cover 12, the case 11 having an opening, the end cover 12 sealing the opening, and the end cover 12 being a wall portion 13.

[0208] It can be understood that the electrode terminals 3 are installed on the end cover 12. The end cover 12 may be connected to the housing 11 by welding or seaming or other methods.

[0209] For example, the end cover 12 is a rectangular end cover, and the width direction of the end cover 12 is parallel to the first direction X.

[0210] When assembling the battery cell 10, the electrode terminals 3 are first attached to the end cover 12, then the tabs 22 are connected to the electrode terminals 3, the electrode assembly 2 is then housed in the case 11, and finally the end cover 12 is connected to the case 11 to seal the opening of the case 11. This structure makes it easier to attach the electrode terminals 3 and connect the tabs 22 to the electrode terminals 3.

[0211] An embodiment of the present application provides a battery 100, which includes a battery cell 10 according to any one of the above embodiments.

[0212] An embodiment of the present application provides a power consuming device, comprising a battery cell 10 according to any one of the above embodiments for supplying electrical energy to the power consuming device.

[0213] 8 to 11 , an embodiment of the present application further provides a battery cell 10, which includes a housing 1, an electrode assembly 2, and an electrode terminal 3. The housing 1 is a rectangular parallelepiped and includes an end cover 12 for a case 11. The case 11 has an opening, and the end cover 12 seals the opening of the case 11, with an extraction hole 131 formed in the end cover 12. The electrode assembly 2 is accommodated in the housing 1, and includes an active material application portion 21 and a tab 22. The tab 22 is installed on the end of the active material application portion 21 facing the end cover 12. The electrode terminal 3 includes a terminal body 31 and a limiting portion 32 that are integrally molded. The terminal body 31 is disposed in the drawing hole 131. The limiting portion 32 is configured to limit the removal of the terminal body 31 from the drawing hole 131 in a direction away from the active material coating portion 21. The terminal body 31 faces an intermediate position of the active material coating portion 21 along a first direction X. The limiting portion 32 includes a first extending portion 321 that protrudes from an outer peripheral surface 311 of the terminal body 31 along the first direction X, and a second extending portion 323 that protrudes from the outer peripheral surface 311 of the terminal body 31 in a direction opposite to the first direction X. In the direction along the first direction X, a distance between an end of the second extending portion 323 that is remote from the terminal body 31 and a central axis 312 of the terminal body 31 is a first distance. The first extending portion 321 includes an extending region 3211, and a distance between the extending region 3211 and the central axis 312 is equal to or greater than the first distance. The tab 22 is bent between the electrode terminal 3 and the active material-applied portion 21 and includes a first connecting portion 221, a second connecting portion 222, a third connecting portion 224, and a fourth connecting portion 225. The first connecting portion 221 is connected to the active material-applied portion 21 via a tab root portion 223. The second connecting portion 222 is welded to the side of the extension region 3211 facing the active material-applied portion 21 to form a weld mark region 3216. The first connecting portion 221, the third connecting portion 224, the fourth connecting portion 225, and the second connecting portion 222 are sequentially connected. The second connecting portion 222 and the third connecting portion 224 are disposed opposite each other along the axial direction Z of the terminal body 31. The first connecting portion 221 faces an intermediate position of the active material-applied portion 21 along the first direction X. Here, the first direction X is parallel to the width direction of the end cover 12.

[0214] Here, the battery cell 10 further includes a first insulating member 8, and in the direction along the axial direction Z of the terminal body 31, the first insulating member 8 includes a first insulating portion 81 that is installed between the first extension portion 321 and the wall portion 13, and an escape groove 3215 is installed on the side of the first extension portion 321 facing the first insulating portion 81, and the orthogonal projections of the weld mark region 3216 and the escape groove 3215 in a plane perpendicular to the axial direction Z of the terminal body 31 at least partially overlap.

[0215] In this battery cell 10, the second connection portion 222 is located on the side of the first connection portion 221 along the first direction X, and the second connection portion 222 is connected to the first extension portion 321 that protrudes from the outer peripheral surface 311 of the terminal body 31 along the first direction X of the limiting portion 32. This shortens the length of the second connection portion 222, thereby shortening the length of the tab 22, reducing the possibility of misalignment and wrinkles occurring in the tab 22 during the manufacturing process and improving the reliability of the battery cell 10. Because the first extension portion 321 has the extension region 3211 and the second connection portion 222 is connected to the extension region 3211, the length of the tab 22 can be further shortened. Since the escape groove 3215 is provided in the first extension portion 321, the first extension portion 321 and the first insulating portion 81 are less likely to come into direct contact in the area corresponding to the escape groove 3215, which makes it possible to delay or prevent heat transfer between the first extension portion 321 and the first insulating portion 81, thereby reducing the possibility of melting of the first insulating portion 81 due to heat transfer from the first extension portion 321 to the first insulating portion 81 and reducing the possibility of poor insulation of the first insulating portion 81.

[0216] It should be noted that, unless contradictory, the embodiments and features of the embodiments in the present application can be combined with each other.

[0217] The above embodiments are merely for illustrating the technical solution of the present application, and are not intended to limit the present application. Those skilled in the art will appreciate that the present application may make various modifications and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application should fall within the protection scope of this application.

Claims

1. A battery cell, a housing including a wall portion having an extraction hole; an electrode assembly accommodated in the housing and including an active material application portion and a tab, the tab being attached to an end of the active material application portion facing the wall portion; an electrode terminal including a terminal body and a limiting portion, the terminal body being drilled in the pull-out hole, the limiting portion being configured to limit the terminal body from being removed from the pull-out hole in a direction away from the active material coating portion, and the limiting portion including a first extending portion protruding from an outer peripheral surface of the terminal body in a first direction; wherein the tab includes a first connection portion and a second connection portion, the second connection portion is located on a side of the first connection portion along the first direction, the first connection portion is connected to the active material coating portion, The second connection portion is connected to the first extension portion.

2. The limiting portion further includes a second extending portion that protrudes from the outer circumferential surface of the terminal body in a direction opposite to the first direction, a distance along the first direction between an end of the second extension portion away from the terminal body and a central axis of the terminal body is a first distance; the first extension portion includes an extension region, a distance between the extension region and the central axis is equal to or greater than a first distance; The battery cell according to claim 1 , wherein the second connection portion is connected to the extension region.

3. a distance along the first direction between an end of the second connection portion close to the terminal body and the central axis is a second distance; The battery cell according to claim 2 , wherein the second distance is equal to or greater than the first distance.

4. 4. The battery cell according to claim 1, wherein the first connection portion faces an intermediate position of the active material application portion along the first direction, and / or the terminal body faces an intermediate position of the active material application portion along the first direction.

5. 5. The battery cell according to claim 1, wherein the tab further includes a third connection portion and a fourth connection portion, the first connection portion, the third connection portion, the fourth connection portion, and the second connection portion are connected in sequence, and the second connection portion and the third connection portion are disposed opposite each other along the axial direction of the terminal body.

6. The battery cell according to any one of claims 1 to 5, wherein the second connection portion is connected to a side of the first extension portion facing the active material application portion along the axial direction of the terminal body.

7. The battery cell according to any one of claims 1 to 6, wherein the terminal body and the limiting portion are integrally formed.

8. 8. The battery cell according to claim 1, further comprising a first insulating member, the first insulating member including a first insulating portion disposed between the first extension portion and the wall portion in a direction along the axial direction of the terminal body, and a heat insulating structure being disposed on a side of the first insulating portion facing the first extension portion and / or a side of the first extension portion facing the first insulating portion.

9. The battery cell according to claim 8 , wherein the heat insulating structure includes a relief groove provided in the first insulating portion and / or the first extending portion.

10. the second connection portion is welded to the first extension portion to form a weld mark region; The battery cell according to claim 9 , wherein the weld mark region and the relief groove are orthogonally projected on a plane perpendicular to the axial direction of the terminal body so as to at least partially overlap each other.

11. The area of ​​the orthogonal projection of the weld mark region on the plane is S １ and the area of ​​the overlapping region of the orthogonal projection of the weld mark region and the relief groove on the plane is S ２ and S ２ / S １ 11. The battery cell according to claim 10, wherein the battery cell satisfies ≧1 / 3.

12. S ２ / S １ 12. The battery cell of claim 11, wherein:

13. The battery cell according to any one of claims 1 to 12, wherein a fusion portion is formed in the first extension portion.

14. 14. The battery cell according to claim 13, wherein a through hole is provided in the first extension portion, and both ends of the through hole extend to two surfaces of the first extension portion that are opposite each other along the axial direction of the terminal body, thereby forming adjacent fusing portions.

15. 15. The battery cell of claim 14, wherein a plurality of the through holes are provided in the first extension portion, the plurality of through holes are arranged at a distance from each other along a second direction, and the second direction intersects with the first direction.

16. 16. The battery cell of claim 15, wherein two through holes are provided in the first extension portion, the two through holes extend along the second direction to both ends of the first extension portion, and the fusing portion is located between the two through holes.

17. The battery cell according to any one of claims 13 to 16, further comprising a second insulating member, the second insulating member covering at least a portion of an outer surface of the fusing portion.

18. 18. The battery cell of claim 17, wherein the second insulating member comprises an insulating coating disposed on the outer surface of the fusing portion, an insulating adhesive layer adhered to the outer surface of the fusing portion, or a thermally welded insulating layer thermally welded to the outer surface of the fusing portion.

19. 18. The battery cell of claim 17, wherein the second insulating member includes a second insulating portion and a third insulating portion, the second insulating portion and the third insulating portion define a first space, the fusing portion is housed in the first space, and the second insulating portion and the third insulating portion are detachably connected.

20. 20. The battery cell of claim 19, wherein a first locking portion is provided on the second insulating portion, a second locking portion is provided on the third insulating portion, and the first locking portion and the second locking portion are fitted together.

21. The battery cell according to any one of claims 1 to 20, wherein the limiting portion is provided with a weight reduction structure.

22. 22. The battery cell of claim 21, wherein the weight reduction structure includes a weight reduction hole disposed in the restricting portion, and both ends of the weight reduction hole extend to two opposite surfaces of the restricting portion disposed opposite each other along the axial direction of the terminal body.

23. 23. The battery cell of claim 22, wherein the weight reduction structure includes a plurality of weight reduction holes, the plurality of weight reduction holes being located around the periphery of the terminal body.

24. The battery cell according to claim 22 or 23, wherein the weight reduction holes are provided at four corners of the limiting portion.

25. 23. The battery cell of claim 22, wherein the weight-reducing hole is located in the first extension portion and forms a corresponding fuse portion.

26. The housing includes: a case having an opening; an end cover that seals the opening, The battery cell according to any one of claims 1 to 25, wherein the end cover is the wall portion.

27. A battery comprising the battery cell according to any one of claims 1 to 26.

28. A power consuming device comprising the battery cell of any one of claims 1 to 26 for supplying electrical energy to the power consuming device.

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