Battery monomer, battery and electric device
Patent Information
- Application Number
- CN202480013370.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-28
- Filing Date
- 2024-06-04
- Publication Date
- 2025-09-26
AI Technical Summary
When the extreme ear is bent, the bonding force between the insulating member and the extreme ear leads to the problem of the extreme ear tearing.
By providing a second insulator between the first insulator and the third insulator, the first insulator and the third insulator are connected together, the connection strength is improved, and at least a portion of the transition portion of the pole ear is not fixed to the insulating member to reduce the pulling force of the insulating member to the pole ear.
The connection strength of the insulator on the electrode assembly is improved, the risk of shedding is reduced, and the risk of extreme ear tearing is reduced when the extreme ear is bent.
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Figure CN120712686A_ABST
Abstract
Description
Battery cells, batteries and electrical devices
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] This application claims priority to Chinese patent application No. 202322661304.X, filed on September 28, 2023, entitled “Battery Cell, Battery and Electrical Device,” the entire contents of which are incorporated by reference into this application. Technical Field
[0003] The embodiments of the present application relate to the field of batteries, and in particular to a battery cell, a battery, and an electrical device. Background Art
[0004] Currently, secondary batteries primarily consist of a housing and an electrode assembly housed within it. The housing is equipped with electrode terminals, while the electrode assembly is provided with tabs electrically connected to the electrode terminals. In related art, the tabs are covered with insulating members to protect them. However, covering the tabs with insulating members can cause them to tear, thus minimizing the risk of tab tearing. Therefore, mitigating this issue has become a new challenge.
[0005] Summary of the Invention
[0006] In view of this, the embodiments of the present application provide a battery cell, a battery, and an electrical device, which are conducive to solving the problem of tab tearing caused by the bonding force between the insulating component and the tab when the tab is bent.
[0007] In a first aspect, a battery cell is provided, comprising: an electrode lead-out portion for leading out electrical energy of the battery cell; an electrode assembly, comprising a main body and a tab, the tab comprising a transition portion and a connecting portion, the connecting portion being bent relative to the transition portion, the transition portion being connected between the main body and the connecting portion, and the connecting portion being used to connect to the electrode lead-out portion; an insulating member, arranged on the inner side of the bend of the tab, the insulating member comprising a first insulator fixed to the main body and a third insulator fixed to the connecting portion, the insulating member further comprising a second insulator connected between the first insulator and the third insulator, and at least a portion of the transition portion being not fixed to the insulating member.
[0008] In the embodiments of the present application, by providing a second insulator between the first and third insulators to connect the first and third insulators together, the connection strength between the first and third insulators on the electrode assembly can be improved, reducing the risk of detachment. Furthermore, by leaving at least a portion of the transition portion from the tab unattached to the insulating member, the pulling force of the insulating member on the tab can be reduced during tab bending, thereby reducing the risk of tab tearing during tab bending.
[0009] In a possible implementation manner, at least a portion of the transition portion is not fixed to the second insulator.
[0010] In this embodiment, by not fixing at least a portion of the transition portion of the tab to the second insulator, the tab can release stress during the tab bending process, reducing the tension exerted on the tab by the insulating component and lowering the risk of tab breakage.
[0011] In one possible implementation, the transition portion includes a first part and a second part, the first part is connected to the main body, the second part is connected between the connecting portion and the first part, the inner surface of the second part is bent relative to the inner surface of the first part, and the second part is not fixed to the second insulator.
[0012] In this embodiment, since the connection points between the second part and the connecting part and the first part are all bending points, by setting the second part not to be fixed to the second insulator, the pulling force of the insulating component on the bending part of the tab can be released as much as possible, thereby reducing the risk of tearing the tab as much as possible when the tab is bent.
[0013] In a possible implementation, a first edge portion of the first part connected to the second part is not fixed to the second insulator, and / or a second edge portion of the connecting portion connected to the second part is not fixed to the second insulator.
[0014] In this embodiment, not only is the second part set to be not fixed to the second insulator, but the first edge portion of the first part connected to the second part is also set to be not fixed to the second insulator, and / or the second edge portion of the connecting part connected to the second part is set to be not fixed to the second insulator, which can better release the pulling force applied by the insulating component to the tab and reduce the risk of the tab breaking.
[0015] In a possible implementation, all transition portions are not fixed to the second insulator.
[0016] In this embodiment, by arranging the entire transition portion not to be fixed to the second insulator, the tension exerted on the tab by the insulating member can be largely released during the tab bending process, thereby reducing the risk of tab breakage.
[0017] In a possible implementation, the connecting portion and the electrode lead portion are welded to form a fusion region, the fusion region is exposed on a side of the connecting portion close to the main body, and the third insulator covers the fusion region.
[0018] In this embodiment, by setting the third insulator to cover the welding area, the third insulator can fix the metal debris in the welding area at the welding area, which is beneficial to reduce the probability of battery cell short circuit caused by the escape of metal debris.
[0019] In a possible implementation, the third insulator extends beyond the welding area.
[0020] In this embodiment, by arranging the third insulator to extend beyond the welding area, the metal debris in the welding area can be sealed in the welding area, thereby reducing the probability of short circuit of the battery cell due to the escape of the metal debris.
[0021] In a possible implementation, the tab extends from the first end surface of the main body, the first insulator is spaced apart from the first connection point, and the first connection point is the connection point between the inner surface of the tab and the first end surface.
[0022] In this embodiment, since the first connection is a stress concentration point between the tab and the main body, the first insulator is spaced apart from the first connection so that the first connection can be covered by the second insulator and is not fixed to the insulating component. Therefore, during the bending process of the tab, the tension applied by the insulating component to the first connection is reduced, thereby reducing the risk of the tab breaking.
[0023] In a possible implementation, a distance between the first insulator and the first connection point is greater than or equal to 2 mm.
[0024] In this embodiment, by setting the distance between the first insulator and the first connection point to be greater than or equal to 2 mm, the tension applied by the insulating component to the tab can be further reduced, thereby reducing the risk of tab breakage.
[0025] In one possible implementation, in the first direction, the size of the first insulator fixed to the first side surface of the main body is smaller than the size of the coated thinning area of the electrode piece in the electrode assembly, the first side surface is perpendicular to the first end surface, and the first direction is perpendicular to the first end surface, and the first end surface is the end surface of the main body connected to the electrode ear.
[0026] In this embodiment, in the first direction, the size of the first insulator fixed to the first side surface of the main body is set to be smaller than the size of the coated thinning area of the electrode sheet in the electrode assembly, which can reduce the impact of the fitting of the insulating component on the performance of the battery cell.
[0027] In one possible implementation, the first insulator includes a first insulating layer and a first adhesive coating, the third insulator includes a third insulating layer and a third adhesive coating, the first insulating layer is bonded to the main body through the first adhesive coating, and the third insulating layer is bonded to the connecting part through the third adhesive coating; the second insulator includes a second insulating layer, and the surface of the second insulating layer facing the tab is exposed.
[0028] In this embodiment, by leaving the surface of the second insulating layer facing the tab exposed, at least a portion of the tab's transition portion is not fixed to the second insulator. This reduces the tensile force exerted on the tab by the insulating member during the tab bending process, thereby lowering the risk of tab breakage. Furthermore, this reduces the amount of adhesive coating material used, thereby lowering costs.
[0029] In one possible implementation, the first insulator includes a first insulating layer and a first adhesive coating, the second insulator includes a second insulating layer and a second adhesive coating, and the third insulator includes a third insulating layer and a third adhesive coating; the second insulator also includes a fourth insulating layer, the fourth insulating layer is bonded to the second insulating layer through the second adhesive coating, and the surface of the fourth insulating layer facing the tab is exposed.
[0030] In this embodiment, by adhering the fourth insulating layer to the second adhesive coating and leaving its surface facing the tab exposed, the portion of the tab from the first connection to the second connection is not fixed to the insulating member. This reduces the tensile force exerted by the insulating member on the tab during bending, thereby lowering the risk of tab breakage. Furthermore, the fourth insulating layer only needs to be attached to the portion of the tab from the first connection to the second connection, reducing the complexity of manufacturing the insulating member.
[0031] In one possible implementation, the electrode lead-out portion includes an electrode terminal, which is welded to the connecting portion; or, the electrode lead-out portion includes an electrode terminal and a connecting member, the connecting portion is electrically connected to the electrode terminal via the connecting member, and the connecting portion is welded to the connecting member.
[0032] In this embodiment, the electrode terminals are directly welded to the connecting portion without connecting them through a connecting member, which can reduce costs while improving the space utilization of the battery cell. Connecting the connecting portion to the electrode terminal through a connecting member facilitates the connection between the tab and the electrode terminal.
[0033] In a possible implementation, the electrode lead portion is provided on the first wall of the housing of the battery cell, the electrode tab extends from the first end surface of the electrode assembly, and the first end surface is provided opposite to the first wall.
[0034] In this embodiment, by arranging the electrode lead portion on the first wall opposite to the first end surface, the space occupied by the tab can be greatly saved.
[0035] In a second aspect, a battery is provided, comprising the battery cell provided in the first aspect.
[0036] According to a third aspect, an electrical device is provided, comprising the battery according to the second aspect, wherein the battery is used to provide electrical energy to the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS
[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.
[0038] FIG1 is a schematic structural diagram of a vehicle disclosed in an embodiment of the present application.
[0039] FIG2 is a schematic structural diagram of a battery disclosed in an embodiment of the present application.
[0040] FIG3 is a schematic exploded view of a battery cell disclosed in an embodiment of the present application.
[0041] FIG4 shows a schematic exploded view of a battery cell according to another embodiment of the present application.
[0042] FIG5 shows a schematic cross-sectional view of a battery cell according to an embodiment of the present application.
[0043] FIG. 6 shows a schematic enlarged view of portion A in FIG. 5 .
[0044] FIG7 shows another schematic cross-sectional view of a battery cell according to an embodiment of the present application.
[0045] FIG8 shows a side view of a pole piece in the electrode assembly before being bent.
[0046] FIG9 shows a schematic cross-sectional view of a battery cell before the tab is bent according to an embodiment of the present application.
[0047] FIG10 shows a schematic cross-sectional view of an insulating component in an expanded state according to an embodiment of the present application.
[0048] FIG11 shows a schematic cross-sectional view of another insulating member in an expanded state according to an embodiment of the present application.
[0049] Explanation of Reference Numerals: 1-Vehicle; 80-Motor; 60-Controller; 100-Battery; 111-First Housing; 112-Second Housing; 20-Battery Cell; 211-Casing; 212-Cover; 22-Electrode Assembly; 23-Connecting Member; 24-Insulating Member; 214-Electrode Terminal; 214a-Positive Electrode Terminal; 214b-Negative Electrode Terminal; 221-Electrode Tab; 221a-First Electrode Tab; 221b-Second Electrode Tab; 222-Main Body; 2221-First End Surface; 2222-First Side Surface; 2211-Transition Portion; 2212-Connecting Portion; 201-Electrode Lead-Out Portion; 202-Welding Region; 203-First Connection Point; 204-Second Connection Point; 241-first insulator; 242-second insulator; 243-third insulator; 2411-first insulating layer; 2412-first adhesive coating; 2421-second insulating layer; 2422-second adhesive coating; 2431-third insulating layer; 2432-third adhesive coating; 2423-fourth insulating layer; 2301-first part; 2302-second part; 401-inner surface of the second part; 402-inner surface of the first part; 403-first edge portion; 404-second edge portion; 2223-second side surface; 405-inner surface of the tab; 251-current collector; 252-active material; X-first direction; Y-expansion direction of the insulating member. DETAILED DESCRIPTION
[0050] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0051] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.
[0052] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.
[0053] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.
[0054] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.
[0055] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).
[0056] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.
[0057] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.
[0058] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.
[0059] 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.
[0060] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.
[0061] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).
[0062] As an example, the positive active material may include at least one of the following materials: a lithium-containing phosphate, a lithium transition metal oxide, and modified compounds thereof.
[0063] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.
[0064] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).
[0065] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.
[0066] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate.
[0067] 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.
[0068] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.
[0069] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical and mechanical stability can be selected.
[0070] As an example, the main material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics.
[0071] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.
[0072] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, and the electrolyte can be selected based on needs. The electrolyte can be liquid, gel, or solid.
[0073] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.
[0074] In some embodiments, the electrode assembly is a laminate structure.
[0075] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.
[0076] As an example, multiple positive electrode sheets may be provided, and the negative electrode sheet is folded to form multiple stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.
[0077] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.
[0078] As an example, multiple separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.
[0079] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.
[0080] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.
[0081] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.
[0082] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film. The housing includes a shell and a cover.
[0083] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, and a polygonal battery. The polygonal battery is, for example, a hexagonal battery, etc. There is no special limitation in this application.
[0084] The battery mentioned in the embodiments of the present application may include one or more battery cells to provide a single physical module with higher voltage and capacity. When there are multiple battery cells, the multiple battery cells are connected in series, in parallel or in hybrid through a busbar.
[0085] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.
[0086] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are housed in the case.
[0087] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.
[0088] Currently, a battery cell mainly includes a shell and an electrode assembly arranged in the shell. The shell is provided with electrode terminals, and the electrode assembly is provided with tabs. The tabs are directly or indirectly electrically connected to the electrode terminals to realize the extraction of electrical energy inside the battery cell to the outside of the battery cell.
[0089] In order to protect the tab, an insulating member is covered on the tab in the related art. However, if the insulating member is bonded to the tab on its entire surface, the tab bonded to the insulating member may be torn when the tab is bent.
[0090] In view of this, an embodiment of the present application provides a battery cell, which helps solve the problem of tab tearing caused by the bonding force between the insulating component and the tab when the tab is bent by setting the transition portion of the tab to be not fixed to the insulating component.
[0091] The technical solutions described in the embodiments of the present application are applicable to various battery-powered devices, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, electric vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.
[0092] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the devices described above, but can also be applied to all devices using batteries. However, for the sake of simplicity, the following embodiments are explained using electric vehicles as an example.
[0093] For example, as shown in FIG1 , it is a structural schematic diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 80, a controller 60 and a battery 100 may be provided inside the vehicle 1. The controller 60 is used to control the battery 100 to supply power to the motor 80. For example, a battery 100 may be provided at the bottom, front or rear of the vehicle 1. The battery 100 may be used to power the vehicle 1. For example, the battery 100 may be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1. In another embodiment of the present application, the battery 100 may not only be used as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.
[0094] For example, as shown in FIG2 , it is a schematic structural diagram of a battery 100 according to an embodiment of the present application. The battery 100 may include a plurality of battery cells 20. In addition to the battery cells 20, the battery 100 may also include a case, the interior of which is a hollow structure, and a plurality of battery cells 20 may be accommodated in the case. As shown in FIG2 , the case may include two parts, which are respectively referred to as a first case portion 111 and a second case portion 112, and the first case portion 111 and the second case portion 112 are snapped together. The shapes of the first case portion 111 and the second case portion 112 may be determined according to the shape of the combination of the plurality of battery cells 20, and at least one of the first case portion 111 and the second case portion 112 has an opening. For example, as shown in FIG2 , only one of the first case portion 111 and the second case portion 112 is a hollow cuboid with an opening, and the other is plate-shaped to cover the opening. Here, for example, the second housing portion 112 is a hollow rectangular parallelepiped with only one open face, and the first housing portion 111 is plate-shaped. The first housing portion 111 covers the opening of the second housing portion 112 to form the housing 11 with a closed chamber. This chamber can be used to accommodate multiple battery cells 20. The multiple battery cells 20 are connected in parallel, series, or in a mixed combination and then placed in the housing formed by the first housing portion 111 and the second housing portion 112 being fastened together.
[0095] For another example, unlike that shown in FIG2 , the first and second housing portions 111, 112 can each be a hollow cuboid with only one open face. The opening of the first and second housing portions 111, 112 are positioned opposite each other, and the first and second housing portions 111, 112 are engaged with each other to form a housing having a closed chamber. Multiple battery cells 20 are connected in parallel, series, or in a mixed series arrangement and then placed within the housing formed by the engagement of the first and second housing portions 111, 112.
[0096] Fig. 3 shows a schematic exploded view of a battery cell 20 according to one embodiment of the present application. Fig. 4 shows a schematic exploded view of a battery cell 20 according to another embodiment of the present application.
[0097] As shown in Figures 3 and 4, a battery cell 20 includes one or more electrode assemblies 22, a housing 211, and a cover plate 212. The walls of the housing 211 and the cover plate 212 are collectively referred to as the walls of the battery cell 20. The shape of the housing 211 depends on the shape of the one or more electrode assemblies 22 after assembly. For example, the housing 211 can be a hollow rectangular parallelepiped, a cube, or a cylinder, with one of its faces having an opening to allow the one or more electrode assemblies 22 to be placed within the housing 211. For example, when the housing 211 is a hollow rectangular parallelepiped or a cube, one of the planes of the housing 211 is an open face, meaning that the plane has no walls, allowing the inside and outside of the housing 211 to communicate. When the housing 211 is a hollow cylinder, the end faces of the housing 211 are open faces, meaning that the end faces have no walls, allowing the inside and outside of the housing 211 to communicate. The cover plate 212 covers the opening and is connected to the housing 211 to form a closed cavity for the electrode assemblies 22. The housing 211 is filled with an electrolyte, such as an electrolyte solution.
[0098] The battery cell 20 further includes two electrode terminals 214. The cover plate 212 is generally in the shape of a flat plate. The two electrode terminals 214 are fixed on the flat surface of the cover plate 212. The two electrode terminals 214 are respectively a positive electrode terminal 214a and a negative electrode terminal 214b.
[0099] As shown in Figures 3 and 4, each electrode assembly 22 has a tab 221, including a first tab 221a and a second tab 221b. The polarity of the first tab 221a and the second tab 221b is opposite. When the first tab 221a is a positive tab, the second tab 221b is a negative tab. For example, as shown in Figure 3, the first tab 221a of one or more electrode assemblies 22 is connected to the positive electrode terminal 214a, and the second tab 221b of one or more electrode assemblies 22 is connected to the negative electrode terminal 214b. For another example, as shown in Figure 4, the first tab 221a of one or more electrode assemblies 22 is connected to the positive electrode terminal 214a via a connecting member 23, and the second tab 221b of one or more electrode assemblies 22 is connected to the negative electrode terminal 214b via another connecting member 23.
[0100] As an example, a pressure relief mechanism 213 may be further provided on one wall of the battery cell 20. The pressure relief mechanism 213 is configured to be activated to release the internal pressure or temperature of the battery cell 20 when the internal pressure or temperature reaches a threshold.
[0101] Optionally, the pressure relief mechanism 213 may be provided on the cover plate 212 or on any wall of the housing 211 .
[0102] As shown in FIG3 and FIG4 , the battery cell 20 further includes an insulating member 24 . The insulating member 24 is disposed on a side of the tab 221 away from the cover plate 212 and is fixedly connected to the tab 221 to provide insulation.
[0103] Figure 5 shows a cross-sectional view of a battery cell 20 according to an embodiment of the present application. Figure 6 is an enlarged schematic view of portion A in Figure 5. Figure 7 is another cross-sectional view of a battery cell 20 according to an embodiment of the present application. As shown in Figure 5, the battery cell 20 includes: an electrode lead-out portion 201, which is used to lead out the electrical energy of the battery cell 20; an electrode assembly 22, which includes a main body 222 and a pole ear 221, the pole ear includes a transition portion 2211 and a connecting portion 2212, the connecting portion 2212 is bent relative to the transition portion 2211, the transition portion 2211 is connected between the main body 222 and the connecting portion 2212, and the connecting portion 2212 is used to connect to the electrode lead-out portion 201; an insulating member 24, which is arranged on the inner side of the bend of the pole ear 221, the insulating member 24 includes a first insulator 241 fixed to the main body 222 and a third insulator 243 fixed to the connecting portion 2212, the insulating member 24 also includes a second insulator 242 connected between the first insulator 241 and the third insulator 243, and at least a portion of the transition portion 2211 is not fixed to the insulating member 24.
[0104] It should be understood that the electrode lead-out portion 201 is used to lead the electrical energy of the battery cell 20 out of the battery cell 20 and to connect it in series or parallel with other battery cells. The electrode lead-out portion 201 can include an electrode terminal 214 as shown in Figure 3, wherein the tab 221 is directly electrically connected to the electrode terminal 214; or, as shown in Figure 4, the electrode lead-out portion 201 can include an electrode terminal 214 and a connecting member 23, wherein the tab 221 is electrically connected to the electrode terminal 214 via the connecting member 23. In some embodiments, the connection portion 2212 of the tab 221 is welded to the electrode lead-out portion 201 to form a fusion region 202.
[0105] Typically, the electrode assembly 22 is formed by overlapping multiple pole pieces, each of which includes a current collector and an active material coated on the surface of the current collector. The portion coated with the active material can be understood as the main body 222 of the electrode assembly 22, while the portion not coated with the active material can be understood as the electrode tab 221 of the electrode assembly 22. Specifically, the portions of the multiple pole pieces coated with the active material form the main body 222, and the portions of the multiple pole pieces not coated with the active material form the electrode tab 221. Furthermore, since each pole piece has a portion not coated with the active material, the portions of the multiple pole pieces not coated with the active material need to be gathered before they can be electrically connected to the electrode lead 201. The portions of the multiple pole pieces not coated with the active material are gathered and then bent to form a transition portion 2211 and a connecting portion 2212, with the connecting portion 2212 being bent relative to the transition portion 2211.
[0106] 7 , the tab 221 may be formed by extending from the first end surface 2221 of the main body 222. After being bent, the connecting portion 2212 of the tab 221 may be disposed opposite to the first end surface 2221.
[0107] It should be explained that the insulating member 24 is disposed on the inner side of the bent electrode tab 221 , which can be understood as the insulating member 24 being disposed on the side of the electrode tab 221 away from the electrode lead-out portion 201 .
[0108] In one example, the tab 221 extends from a portion of the first end surface 2221 of the main body 222. In this example, the first insulator 241 is fixed to a portion of the first end surface 2221 where the tab 221 is not extended, and to a portion of the first side surface 2222 intersecting the first end surface 2221. Furthermore, the first insulator 241 fixed to a portion of the first end surface 2221 where the tab 221 is not extended and to a portion of the first side surface 2222 intersecting the first end surface 2221 are connected. The third insulator 243 can be fixed to at least the portion of the connecting portion 2212 in the weld region 202. The second insulator 242 is connected between the first insulator 241 and the third insulator 243, and the surface of the second insulator 242 facing the tab 221 is exposed.
[0109] In another example, the tab 221 extends from the entire first end surface 2221 of the main body 222. In this example, the first insulator 241 may be fixed only to a portion of the first side surface 2222 intersecting the first end surface 2221, while the second insulator 242, when projected onto the first end surface 2221, substantially covers the entire first end surface 2221.
[0110] In some embodiments, the exposed portion of the surface of the insulating member 24 facing the tab 221 may only cover a portion of the transition portion 2211 . In other embodiments, the exposed portion of the surface of the insulating member 24 facing the tab 221 may also cover the entire transition portion 2211 .
[0111] In the embodiment of the present application, by disposing a second insulator 242 between the first insulator 241 and the third insulator 243 to connect the first insulator 241 and the third insulator 243 together, the connection strength of the first insulator 241 and the third insulator 243 on the electrode assembly 22 can be improved, reducing the risk of detachment. In addition, by not securing at least a portion of the transition portion 2211 from the tab 221 to the insulating member 24, the pulling force of the insulating member 24 on the tab 221 can be reduced during the bending process of the tab 221, which helps to reduce the problem of tab tearing when the tab 221 is bent.
[0112] In some embodiments, at least a portion of the transition portion 2211 is not fixed to the second insulator 242 .
[0113] As shown in Figures 5 to 7, the second insulator 242 covers at least part of the transition portion 2211. Therefore, at least part of the transition portion 2211 is not fixed to the insulating member 24. It can also be understood that at least part of the transition portion 2211 is not fixed to the second insulator 242.
[0114] In this embodiment, by not fixing at least a portion of the transition portion 2211 of the tab 221 to the second insulator 242, the tab 221 can release stress during the bending process of the tab 221, reducing the tension applied by the insulating component 24 to the tab 221 and reducing the risk of the tab 221 breaking.
[0115] In some embodiments, as shown in Figure 6, the transition portion 2211 includes a first part 2031 and a second part 2032, the first part 2031 is connected to the main body 222, the second part 2032 is connected between the connecting portion 2212 and the first part 2031, the inner surface 401 of the second part 2032 is bent relative to the inner surface 402 of the first part 2031, and the second part 2032 is not fixed to the second insulator 242.
[0116] It should be noted that the inner surface 401 of the second portion 2032 is bent relative to the inner surface 402 of the first portion 2031 , which may also mean that there is an angle between the inner surface 401 of the second portion 2032 and the inner surface 402 of the first portion 2031 .
[0117] In some embodiments, as shown in Figures 5 to 7, the outer surface of the second part 2032 and the outer surface of the first part 2031 can be in the same plane. For example, the outer surface of the second part 2032 and the outer surface of the first part 2031 can be in the same plane as the second side surface 2223 of the main body 222.
[0118] In this embodiment, since the connection points between the second part 2032 and the connecting part 2212 and the first part 2031 are all bending points, by setting the second part 2032 not to be fixed to the second insulator 242, the pulling force of the insulating component 24 on the bending part of the pole ear 221 can be released as much as possible, thereby reducing the risk of tearing the pole ear 221 as much as possible when the pole ear 221 is bent.
[0119] In some embodiments, as shown in FIG. 6 , the first edge portion 403 of the first part 2031 connected to the second part 2032 is not fixed to the second insulator 242 , and / or the second edge portion 404 of the connecting portion 2212 connected to the second part 2032 is not fixed to the second insulator 242 .
[0120] In other words, in a direction perpendicular to the first side 2222, the third insulator 243 and the bending point 205 between the transition portion 2211 and the connecting portion 2212 are spaced apart, and / or, in a direction perpendicular to the first side 2222, the first insulator 241 and the second connection 204 between the first part 2031 and the second part 2032 are spaced apart.
[0121] It should be noted that, for the sake of convenience, Figure 6 only points out the edge of the inner surface 402 of the first part 2031 as the first edge portion 403, and the edge of the inner surface of the connecting portion 2212 as the second edge portion 404, but those skilled in the art understand that the first edge portion 403 and the second edge portion 404 should be three-dimensional structures.
[0122] In this embodiment, not only is the second part 2032 set to be not fixed to the second insulator 242, but the first edge portion 403 of the first part 2031 connected to the second part 2032 is also set to be not fixed to the second insulator 242, and / or the second edge portion 404 of the connecting portion 2212 connected to the second part 2032 is set to be not fixed to the second insulator 242, which can better release the pulling force applied by the insulating component 24 to the pole ear 221 and reduce the risk of the pole ear 221 breaking.
[0123] In other embodiments, the entire transition portion 2211 is not fixed to the second insulator 242 .
[0124] That is, not only the second portion 2032 of the transition portion 2211 is not fixed to the second insulator 242 , but also the first portion 2031 of the transition portion 2211 is not fixed to the second insulator 242 .
[0125] In this embodiment, by disposing the entire transition portion 2211 not fixed to the second insulator 242 , the tension applied by the insulating member 24 to the tab 221 can be largely released during the bending process of the tab 221 , thereby reducing the risk of the tab 221 breaking.
[0126] In some embodiments, the connection portion 2212 is welded to the electrode lead portion 201 to form a fusion region 202 . The fusion region 202 is exposed on a side of the connection portion 2212 close to the main body 222 . The third insulator 243 covers the fusion region 202 .
[0127] For example, the orthographic projection of the welding region 202 on the first end surface 2221 is located within the orthographic projection of the third insulator 243 on the first end surface 2221 .
[0128] In some embodiments, the connection portion 2212 and the electrode lead portion 201 can be connected by ultrasonic welding. For example, a welding head is disposed on a side of the connection portion 2212 away from the electrode lead portion 201, and a welding seat is disposed on a side of the electrode lead portion 201 away from the connection portion 2212. When welding the connection portion 2212 and the electrode lead portion 201, the welding head and the welding seat clamp the connection portion 2212 and the electrode lead portion 201, and form a fusion region 202 between the electrode lead portion 201 and the connection portion 2212. The fusion region 202 can be exposed on the surface of the connection portion 2212 near the main body 222.
[0129] In this embodiment, by setting the third insulator 243 to cover the welding area 202, the third insulator 243 can fix the metal debris in the welding area 202 at the welding area 202, which is beneficial to reduce the probability of short circuit of the battery cell 20 due to the escape of metal debris.
[0130] In some embodiments, the third insulator 243 extends beyond the weld region 202 .
[0131] It should be noted that although Figure 7 only shows that the third insulator 243 extends beyond the welding area 202 in the direction perpendicular to the first side surface 2222, those skilled in the art understand that the third insulator 243 in the embodiment of the present application extends beyond the welding area 202, which may mean that the third insulator 243 extends beyond the welding area 202 in all directions on the plane parallel to the first end face 2221.
[0132] In this embodiment, by disposing the third insulator 243 beyond the welding region 202 , the metal debris in the welding region 202 can be sealed in the welding region 202 , thereby reducing the probability of the battery cell 20 short-circuiting due to the escape of the metal debris.
[0133] In some embodiments, the third insulator 243 extends beyond the weld region 202 by 2 mm or more.
[0134] In some examples, the third insulator 243 extends beyond the weld region 202 by 2 mm or 3 mm. For example, A1 in FIG7 is 3 mm. For another example, A2 in FIG7 is 2 mm.
[0135] In some embodiments, as shown in FIG. 7 , the tab 221 extends from the first end surface 2221 of the body 222 , and the first insulator 241 is spaced apart from the first connection 203 . The first connection 203 is the connection between the inner surface 405 of the tab 221 and the first end surface 2221 .
[0136] First, it should be explained that the inner surface 405 of the tab 221 may include the inner surface 402 of the first portion 2031, the inner surface 401 of the second portion 2032, and the inner surface of the connection portion 2212. Furthermore, as described above, the tab 221 may extend from a portion of the first end surface 2221 of the main body 222, and the first insulator 241 may secure a portion of the first end surface 2221. In this embodiment of the present application, the second insulator 242 may extend beyond the first connection 203, so that the second insulator 242 may also cover a portion of the first end surface 2221, thereby allowing a portion of the first end surface 2221 to be unsecured to the insulating member 24.
[0137] In this embodiment, since the first connection 203 is a stress concentration point between the tab 221 and the main body 222, the first insulator 241 is spaced apart from the first connection 203 so that the first connection 203 can be covered by the second insulator 242 and is not fixed to the insulating member 24. Therefore, during the bending process of the tab 221, the pulling force applied by the insulating member 24 to the first connection 203 is reduced, thereby reducing the risk of the tab 221 breaking.
[0138] In some embodiments, the distance between the first insulator 241 and the first connection 203 is greater than or equal to 2 mm.
[0139] In some examples, the distance between the first insulator 241 and the first connection point 203 is equal to 2 mm or 3 mm, etc. For example, A3 in FIG7 is equal to 2 mm.
[0140] In this embodiment, by setting the distance between the first insulator 241 and the first connection point 203 to be greater than or equal to 2 mm, the tension applied by the insulating member 24 to the tab 221 can be further reduced, thereby reducing the risk of the tab 221 breaking.
[0141] In some embodiments, in the first direction X, the dimension A4 of the first insulator 241 fixed to the first side surface 2222 of the main body 222 is smaller than the dimension L of the coated thinning area of the electrode piece in the electrode assembly 22, the first side surface 2222 is perpendicular to the first end surface 2221, and the first direction X is perpendicular to the first end surface 2221, and the first end surface 2221 is the end surface of the main body 222 connected to the electrode ear 221.
[0142] Figure 8 shows a side view of a pole piece in electrode assembly 22 before bending. As can be seen from Figure 8, the area of current collector 251 coated with active material 252, which connects to the area of current collector 251 not coated with active material 252, includes a transition region. The thickness of active material 252 in this transition region gradually decreases, and this transition region can be referred to as a coating thinning region. Multiple pole pieces shown in Figure 8 overlap to form the structure of the electrode assembly shown in Figures 5 to 7 before the tabs 221 are folded.
[0143] Typically, the first insulator 241 extends from the connection between the first side surface 2222 and the first end surface 2221 in a direction away from the first end surface 2221 , and extends to a coating thinning area that does not exceed the pole piece.
[0144] In this embodiment, in the first direction X, the size A4 of the first insulator 241 fixed to the first side surface 2222 of the main body 222 is set to be smaller than the size L of the coated thinning area of the electrode piece in the electrode assembly 22, which can reduce the impact of the fitting of the insulating component 24 on the performance of the battery cell 20.
[0145] In some embodiments, as shown in FIG. 7 , in a direction perpendicular to the first side surface 2222 , a dimension A5 of the second edge portion 404 may also be greater than or equal to 2 mm.
[0146] Figure 9 shows a cross-sectional view of the battery cell 20 before the tab 221 of Figures 5 to 7 is bent. As shown in Figure 9, the distance A6 between the third insulator 243 and the second connection 204 is greater than or equal to 2 mm. The second connection 204 may refer to the connection between the first portion 2031 and the second portion 2032. This distance A6 between the third insulator 243 and the second connection 204 ensures that the second portion 2032 of the tab 221 after bending is at least not fixed to the second insulator 242. Furthermore, it also ensures that the second edge 404 of the connecting portion 2212 is not fixed to the second insulator 242.
[0147] Fig. 10 is a schematic cross-sectional view of an insulating member 24 in an expanded state according to an embodiment of the present application. Fig. 11 is a schematic cross-sectional view of another insulating member 24 in an expanded state according to an embodiment of the present application.
[0148] As shown in Figure 10, the first insulator 241 includes a first insulating layer 2411 and a first adhesive coating 2412, the third insulator 243 includes a third insulating layer 2431 and a third adhesive coating 2432, the first insulating layer 2411 is bonded to the main body 222 through the first adhesive coating 2412, the third insulating layer 2431 is bonded to the connecting portion 2212 through the third adhesive coating 2432, and the second insulator 242 includes a second insulating layer 2421, and the surface of the second insulating layer 2421 facing the tab 221 is exposed.
[0149] It should be understood that the surface of the second insulating layer 2421 facing the tab 221 is exposed, which can be understood as no adhesive coating is provided on the side of the second insulating layer 2421 facing the tab 221 .
[0150] In this embodiment, by leaving the surface of the second insulating layer 2421 facing the tab 221 exposed, at least a portion of the transition portion 2211 of the tab 221 is not fixed to the second insulator 242. This reduces the tension exerted by the insulating member 24 on the tab 221 during the bending process of the tab 221, thereby reducing the risk of breakage of the tab 221. Furthermore, the material used for the adhesive coating can be reduced, thereby lowering costs.
[0151] As shown in Figure 11, the first insulator 241 includes a first insulating layer 2411 and a first adhesive coating 2412, the second insulator 242 includes a second insulating layer 2421 and a second adhesive coating 2422, and the third insulator 243 includes a third insulating layer 2431 and a third adhesive coating 2432; the second insulator 242 also includes a fourth insulating layer 2423, which is bonded to the second insulating layer 2421 through the second adhesive coating 2422, and the surface of the fourth insulating layer 2423 facing the tab 221 is exposed.
[0152] It should be understood that the surface of the fourth insulating layer 2423 facing the tab 221 is exposed, which can be understood as no adhesive coating is provided on the side of the fourth insulating layer 2423 facing the tab 221 .
[0153] In this embodiment, by adhering the fourth insulating layer 2423 to the second adhesive coating 2422 and leaving its surface facing the tab 221 exposed, the portion of the tab 221 from the first connection 203 to the second connection 204 is not fixed to the second insulator 242. This reduces the tensile force exerted on the tab 221 by the insulating member 24 during the bending process of the tab 221, thereby reducing the risk of breakage of the tab 221. Furthermore, the fourth insulating layer 2423 only needs to be adhered to at least a portion of the transition portion 2211 of the tab 221, reducing the manufacturing complexity of the insulating member 24.
[0154] The insulating layer in the embodiment of the present application may be made of at least one of PP, PE, and PET. The thickness of the insulating layer plus the adhesive coating may range from 0.001 mm to 0.5 mm. For example, the thickness of the first insulator 241, the thickness of the second insulator 242 (excluding the fourth insulating layer 2423 in FIG. 11 ), and the thickness of the third insulator 243 are all within the range of 0.001 mm to 0.5 mm.
[0155] In some embodiments, the third insulator 243 is spaced apart from the inflection point 205, which can also be understood as the third adhesive coating 2432 being spaced apart from the inflection point 205. In other embodiments, the first insulator 241 is spaced apart from the second connection point 204, which can also be understood as the first adhesive coating 2412 being spaced apart from the second connection point 204. In other embodiments, the first insulator 241 is spaced apart from the first connection point 203, which can also be understood as the first adhesive coating 2412 being spaced apart from the first connection point 203.
[0156] In some embodiments, the first insulator 241 and the third insulator 243 have different colors. For example, the first insulator 241 is yellow, and the third insulator 243 is blue. Furthermore, the different colors of the first insulator 241 and the third insulator 243 can be achieved by having the first adhesive coating 2412 and the third adhesive coating 2432 have different colors.
[0157] In other embodiments, the first insulator 241 and the third insulator 243 have the same color. For example, the first insulator 241 and the third insulator 243 are both blue. Furthermore, the first insulator 241 and the third insulator 243 can have the same color by having the first adhesive coating 2412 and the third adhesive coating 2432 have the same color.
[0158] In some embodiments, the first insulating layer 2411 of the first insulator 241, the second insulating layer 2421 of the second insulator 242, and the third insulating layer 2431 of the third insulator 243 can be integrally formed. The first insulator 241, fixed to the first end surface 2221, can be spaced apart from the first connection 203, or can be spaced apart from the first connection 203 by the first adhesive coating 2412 of the first insulator 241. Similarly, the third insulator 243 can be spaced apart from the second connection 204, or can be spaced apart from the second connection 204 by the third adhesive coating 2432 of the third insulator 243.
[0159] In some other embodiments, at least one of the first insulator 241 , the second insulator 242 , and the third insulator 243 is formed independently.
[0160] In other embodiments, the first insulator 241 may be fixed to the main body 222 by heat-melting, and the third insulator 243 may be fixed to the connecting portion 2212 by heat-melting.
[0161] As shown in Figure 3, the electrode lead-out portion 201 may include an electrode terminal 214, which is welded to the connecting portion 2212; or, as shown in Figure 4, the electrode lead-out portion 201 may include an electrode terminal 214 and a connecting member 23, the connecting portion 2212 is electrically connected to the electrode terminal 214 through the connecting member 23, and the connecting portion 2212 is welded to the connecting member 23.
[0162] In this embodiment, the electrode terminal 214 is directly welded to the connecting portion 2212 without connecting via the connecting member 23, which can reduce costs while improving the space utilization of the battery cell 20. Connecting the connecting portion 2212 to the electrode terminal 214 via the connecting member 23 facilitates the connection between the tab 221 and the electrode terminal 214.
[0163] In some embodiments, the electrode lead portion 201 may be disposed on a first wall of the housing of the battery cell 20 , and the tab 221 extends from a first end surface 2221 of the electrode assembly 22 , with the first end surface 2221 being disposed opposite the first wall.
[0164] Alternatively, the first wall may be any wall of the outer shell of the battery cell 20 , for example, the electrode lead-out portion 201 is provided on the cover plate 212 in FIG. 3 and FIG. 4 .
[0165] In this embodiment, by arranging the electrode lead portion 201 on the first wall opposite to the first end surface 2221 , the space occupied by the electrode tab 221 can be greatly saved.
[0166] In some embodiments, the battery cell 20 may include multiple electrode assemblies 22, for example, two adjacent electrode assemblies 22, which may share one electrode lead-out portion 201. Each electrode assembly 22 may be provided with an insulating member 24 as described in the various embodiments above.
[0167] Referring again to Figures 3 to 11, an embodiment of the present application provides a battery cell 20, including an electrode lead-out portion 201 for leading out electrical energy of the battery cell 20; an electrode assembly 22, including a main body 222 and a pole ear 221 extending from a first end surface 2221 of the main body 222, the pole ear 221 including a transition portion 2211 and a connecting portion 2212, the transition portion 2211 being connected between the main body 222 and the connecting portion 2212, the connecting portion 2212 being bent relative to the transition portion 2211, the connecting portion 2212 being used to be welded to the electrode lead-out portion 201 and form a fusion region 202; an insulating member 24, disposed on the inner side of the bend of the pole ear 221, the insulating member 24 including a first insulator 241 fixed to the main body 222 and a third insulator 243 fixed to the connecting portion 2212, the insulating member 24 also including Connected between the first insulator 241 and the third insulator 243, the entire transition portion 2211 is not fixed to the second insulator 242, and the second edge portion 404 of the connecting portion 2212 connected to the transition portion 2211 is not fixed to the second insulator 242, the third insulator 243 covers and exceeds the welding area 202, and the distance from the third insulator 243 to the first connection 203 is greater than 2 mm, the first connection 203 is the connection between the inner surface 405 of the tab 221 and the first end face 2221, in the first direction X, the size A4 of the first insulator 241 fixed to the first side face 2222 of the main body 222 is smaller than the size L of the coated thinning area of the electrode piece in the electrode assembly 22, the first side face 2222 is disposed at the first end face 2221, and the first direction X is perpendicular to the first end face 2221.
[0168] In this embodiment, by not attaching the entire transition portion 2211 to the second insulator 242, not attaching the second edge portion 404 of the connecting portion 2212 connected to the transition portion 2211 to the second insulator 242, and ensuring that the distance from the third insulator 243 to the first connection 203 is greater than or equal to 2 mm, the problem of the tab 221 being torn due to the adhesive force between the insulating member 24 and the tab 221 when the tab 221 is bent can be resolved. Furthermore, by providing the third insulator 243 to cover and extend beyond the weld region 202, the probability of short-circuiting the battery cell 20 due to the escape of metal debris within the weld region 202 can be reduced.
[0169] The embodiment of the present application further provides a battery, which includes the battery cell 20 of the embodiment of the present application.
[0170] An embodiment of the present application further provides an electrical device, comprising the battery of the above embodiment, wherein the battery is used to provide electrical energy to the electrical device.
[0171] The electric device may be a vehicle as shown in FIG1 , or may be any device using a battery.
[0172] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.
Claims
1. A battery cell, characterized in that: include: An electrode lead-out portion, used to lead out the electrical energy of the battery cell; An electrode assembly, comprising a main body and a tab, wherein the tab comprises a transition portion and a connecting portion, wherein the connecting portion is bent relative to the transition portion, the transition portion is connected between the main body and the connecting portion, and the connecting portion is used to be connected to the electrode lead-out portion; An insulating component is arranged on the inner side of the bent pole ear, the insulating component includes a first insulator fixed to the main body and a third insulator fixed to the connecting portion, the insulating component also includes a second insulator connected between the first insulator and the third insulator, and at least a part of the transition portion is not fixed to the insulating component.
2. The battery cell according to claim 1, characterized in that: At least a portion of the transition portion is not fixed to the second insulator.
3. The battery cell according to claim 2, characterized in that: The transition portion includes a first part and a second part, the first part is connected to the main body, the second part is connected between the connecting portion and the first part, the inner surface of the second part is bent relative to the inner surface of the first part, and the second part is not fixed to the second insulator.
4. The battery cell according to claim 3, characterized in that: A first edge portion of the first portion connected to the second portion is not fixed to the second insulator, and / or a second edge portion of the connecting portion connected to the second portion is not fixed to the second insulator.
5. The battery cell according to any one of claims 2 to 4, characterized in that: All of the transition portions are not fixed to the second insulator.
6. The battery cell according to any one of claims 1 to 5, characterized in that: The connection portion and the electrode lead-out portion are welded to form a fusion region, the fusion region is exposed at a side of the connection portion close to the main body, and the third insulator covers the fusion region.
7. The battery cell according to claim 6, characterized in that: The third insulator extends beyond the fusion bonding area.
8. The battery cell according to any one of claims 1 to 7, characterized in that: The pole lug extends from the first end surface of the main body, the first insulator is spaced apart from a first connection point, and the first connection point is a connection point between the inner surface of the pole lug and the first end surface.
9. The battery cell according to claim 8, characterized in that: The distance between the first insulator and the first connection point is greater than or equal to 2 mm.
10. The battery cell according to any one of claims 1 to 9, characterized in that: In the first direction, the size of the first insulator fixed to the first side surface of the main body is smaller than the size of the coated thinning area of the pole piece in the electrode assembly, the first side surface is perpendicular to the first end surface, and the first direction is perpendicular to the first end surface, and the first end surface is the end surface of the main body connected to the pole ear.
11. The battery cell according to any one of claims 1 to 10, characterized in that: The first insulator includes a first insulating layer and a first adhesive coating, the third insulator includes a third insulating layer and a third adhesive coating, the first insulating layer is bonded to the main body through the first adhesive coating, and the third insulating layer is bonded to the connecting portion through the third adhesive coating; The second insulator includes a second insulating layer, and a surface of the second insulating layer facing the electrode tab is exposed.
12. The battery cell according to any one of claims 1 to 11, characterized in that: The first insulator includes a first insulating layer and a first adhesive coating, the second insulator includes a second insulating layer and a second adhesive coating, and the third insulator includes a third insulating layer and a third adhesive coating; the second insulator also includes a fourth insulating layer, the fourth insulating layer is bonded to the second insulating layer via the second adhesive coating, and the surface of the fourth insulating layer facing the tab is exposed.
13. The battery cell according to any one of claims 1 to 12, characterized in that: The electrode lead-out portion includes an electrode terminal, and the electrode terminal is welded to the connecting portion; or, The electrode lead-out portion includes an electrode terminal and a connecting member, the connecting portion is electrically connected to the electrode terminal through the connecting member, and the connecting portion is welded to the connecting member.
14. The battery cell according to any one of claims 1 to 13, characterized in that: The electrode lead-out portion is disposed on a first wall of a housing of the battery cell, the electrode tab extends from a first end surface of the electrode assembly, and the first end surface is disposed opposite to the first wall.
15. A battery, characterized in that: The invention comprises the battery cell according to any one of claims 1 to 14.
16. An electrical device, characterized in that: The battery as claimed in claim 15 is used to provide electrical energy to the electrical device.