WO2024050697A1 - 电极组件、电池单体、电池、用电设备和极耳整形装置 - Google Patents

电极组件、电池单体、电池、用电设备和极耳整形装置 Download PDF

Info

Publication number
WO2024050697A1
WO2024050697A1 PCT/CN2022/117329 CN2022117329W WO2024050697A1 WO 2024050697 A1 WO2024050697 A1 WO 2024050697A1 CN 2022117329 W CN2022117329 W CN 2022117329W WO 2024050697 A1 WO2024050697 A1 WO 2024050697A1
Authority
WO
WIPO (PCT)
Prior art keywords
tab
pole
electrode assembly
pole piece
tabs
Prior art date
Application number
PCT/CN2022/117329
Other languages
English (en)
French (fr)
Inventor
赵丰刚
金海族
柴志生
谷慧
Original Assignee
宁德时代新能源科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 宁德时代新能源科技股份有限公司 filed Critical 宁德时代新能源科技股份有限公司
Priority to CN202280089801.2A priority Critical patent/CN118556338A/zh
Priority to PCT/CN2022/117329 priority patent/WO2024050697A1/zh
Publication of WO2024050697A1 publication Critical patent/WO2024050697A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors
    • H01M4/70—Carriers or collectors characterised by shape or form
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/531—Electrode connections inside a battery casing
    • H01M50/533—Electrode connections inside a battery casing characterised by the shape of the leads or tabs
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • H01M50/531—Electrode connections inside a battery casing
    • H01M50/538—Connection of several leads or tabs of wound or folded electrode stacks

Definitions

  • the present application relates to the field of battery technology, and in particular to an electrode assembly, a battery cell, a battery, an electrical equipment and a tab shaping device.
  • Rechargeable battery cells which can be called secondary battery cells, refer to battery cells that can be activated by charging to activate active materials and continue to be used after the battery cells are discharged.
  • Rechargeable battery cells are widely used in electronic devices, such as mobile phones, laptops, battery cars, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools.
  • the electrode assembly has some battery performance issues or safety issues related to the tabs during its formation process.
  • This application aims to solve at least one of the technical problems existing in electrode assemblies in the prior art. To this end, one purpose of this application is to provide an electrode assembly, a battery cell, a battery, an electrical device and a tab shaping device.
  • An embodiment of the first aspect of the present application provides an electrode assembly, including: a first pole piece and a second pole piece with opposite polarities, and a separator disposed between the first pole piece and the second pole piece.
  • the first pole piece , the separator and the second pole piece are rolled along the winding direction to form a rolled structure; wherein, at least one of the first pole piece and the second pole piece includes: a current collector; an active material layer, at least disposed on the current collector adjacent to the separator The surface of one side; and the pole ear portion, connected to one side of the current collector extending along the winding direction.
  • the pole ear portion includes a continuous area close to the active material layer and an interval area away from the active material layer.
  • the interval area includes a continuous area along the winding direction. Multiple poles arranged at intervals around the direction.
  • the tab portion is provided with a continuous area and a spacing area.
  • the spacing area includes a plurality of tabs arranged at intervals along the winding direction. These tabs can be formed by processes such as die cutting. By setting continuous The area can provide a certain distance between the tab and the current collector, thereby preventing the active material coating layer on the current collector from falling off when the tab is cut, thereby improving battery performance.
  • the height of the tab before the tab is bent is h0, and the height before the tab is bent is h1.
  • h0 and h1 satisfy: 0.25 ⁇ h1/ h0 ⁇ 1.
  • the height relationship between the tab part and the tab disclosed in this embodiment can not only ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, but also improve the active material coating layer caused by the tab slitting.
  • At least part of the tab is bent relative to the current collector and flattened, and the maximum distance from the bending line to the top of the tab is h2, which is the height of the tab before it is bent in the axial direction of the winding structure.
  • h1 and h2 satisfy: 0.3 ⁇ h2/h1 ⁇ 1.
  • the dimensional relationship between the tab and the bent part disclosed in this embodiment can not only ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, but also improve the electrolyte infiltration performance, improving the electrolysis cycle and power performance. be improved.
  • the winding structure is a cylindrical winding structure
  • the diameter of the central barrel of the winding structure is d
  • the width of the tab is l
  • l and d satisfy: 0.7 ⁇ l/d ⁇ 2.
  • the relationship between the tab width and the diameter of the innermost ring of the winding structure disclosed in this embodiment can ensure that the density of the dense layer formed after the tabs are flattened meets the welding conditions, and at the same time can avoid the tabs from turning over when the bare cell is wound. Loss of quality caused by folding, tearing, etc.
  • the maximum distance between adjacent tabs in the tab portion is g
  • the width of the tab is l
  • l and g satisfy: g/l ⁇ 0.2.
  • the relationship between the tab width and the spacing between the tabs disclosed in this embodiment can ensure that the thickness of the dense layer formed after the tabs are flattened meets the welding conditions, thereby improving the welding quality.
  • the height h0 of the pole part before the pole is not bent satisfies: 3mm ⁇ h0 ⁇ 8mm
  • the height h1 of the pole before it is not bent satisfies : 1mm ⁇ h1 ⁇ 8mm
  • at least part of the tab is bent relative to the current collector and flattened, the maximum distance from the bending line to the top of the tab is h2, h2 satisfies: 1mm ⁇ h2 ⁇ 8mm.
  • the size design of the pole lug, the pole lug and the bent part disclosed in this embodiment can make the pole tabs overlap with each other when flattened to form a denser layer, which significantly reduces the probability of laser welding penetration and improves the welding quality. Improvement, while avoiding problems such as shedding of the active material layer and affecting electrolyte infiltration.
  • the height h0 satisfies: 4mm ⁇ h0 ⁇ 7mm
  • the height h1 satisfies: 2mm ⁇ h1 ⁇ 7mm
  • the distance h2 satisfies: 2mm ⁇ h2 ⁇ 7mm.
  • the dimensional design of the tab portion, tab and bent portion disclosed in this embodiment can make the dense layer formed by overlapping each other when the tabs are flattened more dense. This significantly reduces the probability of laser welding penetration, making it more effective in improving welding quality, preventing the active material layer from falling off, and avoiding affecting electrolyte infiltration.
  • the tab is arranged obliquely relative to one side of the current collector extending along the winding direction.
  • the tabs of the pole piece extend obliquely relative to the side of the current collector, which can further reduce the intensity of the tabs in the interval area, making it easier for the tabs to be squeezed and flattened, which is beneficial to improving the strength of the dense layer formed after the tabs are flattened. Density and thickness, improving welding yield.
  • the tab is tilted in the opposite direction to the winding direction.
  • the tilt direction of the pole tab is opposite to the direction of winding the pole piece.
  • the pole tab is not easy to be folded or damaged, which can improve the yield of the winding structure.
  • At least part of the pole tab is bent and flattened relative to the current collector.
  • the bent portion of the pole tab is bent by rotating and extruding the extrusion head.
  • the tilt direction of the pole tab is consistent with the direction of the extrusion head.
  • the direction of rotation is the same.
  • the tilt direction of the tab is consistent with the rotation direction of the extrusion head, which can avoid damage to the tab during flattening, especially the tabs at the outer ring and the end of the winding structure, which can improve the yield of the winding structure.
  • the inclination angle ⁇ of the pole lug satisfies: 45° ⁇ 90°.
  • the inclination angle ⁇ of the tab disclosed in this embodiment can effectively reduce the bending strength of the tab, making it easier for the tab to be squeezed and flattened, and can effectively prevent the tab from turning over during winding and/or flattening. Folding and breakage issues.
  • a side of the pole located at the end of the winding structure near the tail end is provided with a bevel formed by corner cutting.
  • the pole lug at the end is die-cut so that the corner of the tail end is cut off, which can improve this problem.
  • At least a portion of the bevel is arcuate.
  • An embodiment of the second aspect of the present application provides a battery cell, which includes the electrode assembly in the above embodiment.
  • the tab is bent and flattened relative to the current collector, the maximum distance from the bending line to the top of the tab is h2, the winding structure is a cylindrical winding structure, and the battery cell further includes: a collector
  • the flow plate is located on the side of the cylindrical winding structure connecting the pole lug, and is fixedly connected to the bent part of the pole lug by welding.
  • the thickness of the current collecting plate is t1, and t1 and h2 satisfy: 0.05 ⁇ t1/h2 ⁇ 0.2.
  • the relationship between the height of the bent portion of the tab and the thickness of the current collecting plate disclosed in this embodiment can ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, and at the same time, the battery capacity can be increased.
  • a third embodiment of the present application provides a battery, which includes the battery cell in the above embodiment.
  • a fourth embodiment of the present application provides an electrical device, which includes the battery in the above embodiment, and the battery is used to provide electric energy.
  • An embodiment of the fifth aspect of the present application provides a tab shaping device, including an extrusion head for smoothing the tab in the electrode assembly according to any of the above items, so that at least part of the tab is relative to the assembly.
  • the fluid bends and is flattened.
  • the tab is arranged obliquely relative to one side of the current collector extending along the winding direction; the rotation direction of the extrusion head is configured to be consistent with the inclination direction of the tab.
  • the rotation direction of the extrusion head is consistent with the direction in which the tabs are tilted, which can avoid damaging the tabs during flattening, especially the tabs at the outer ring and the end of the winding structure, which can improve the yield of the winding structure.
  • Figure 1 is a schematic structural diagram of some embodiments of an electrical device according to the present disclosure
  • Figure 2A is a schematic structural diagram of some embodiments of a battery according to the present disclosure.
  • Figure 2B is a schematic structural diagram of the electrical connection of multiple battery cells in some embodiments of the battery according to the present disclosure
  • Figure 3 is a schematic exploded structural view of a battery cell formed according to some embodiments of the battery cell of the present disclosure
  • FIG. 4 is a schematic cross-sectional view of a wound structure formed according to some embodiments of an electrode assembly of the present disclosure
  • Figure 5 is a schematic structural diagram of the first pole piece, the second pole piece and the separator in some embodiments of the electrode assembly according to the present disclosure
  • Figure 6 is a schematic structural diagram of some embodiments of an electrode assembly according to the present disclosure.
  • Figure 7 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure.
  • Figure 8 is a schematic view of an expanded pole piece in some embodiments of an electrode assembly according to the present disclosure.
  • Figure 9 is a schematic cross-sectional view of a pole piece in some embodiments of an electrode assembly according to the present disclosure.
  • Figure 10 is a schematic diagram of an expanded pole piece in other embodiments of an electrode assembly according to the present disclosure.
  • Figure 11 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure.
  • FIG. 12 is an expanded schematic view of the pole piece in other embodiments of the electrode assembly according to the present disclosure.
  • 10A first pole piece
  • 10B second pole piece
  • 10C diaphragm
  • 100 winding structure
  • 11A, 11B, 222 pole lug
  • 12A, 12B active material layer
  • 13A insulation layer
  • 17A, 17B current collector; 14A, 14B: interval area; 15A, 15B: continuous area;
  • 16A, 16B pole lug; 1000: extrusion head; 20: battery cell; 21: shell assembly;
  • an embodiment means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application.
  • the appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.
  • multiple refers to more than two (including two).
  • multiple groups refers to two or more groups (including two groups), and “multiple pieces” refers to It is more than two pieces (including two pieces).
  • Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars, as well as in many fields such as military equipment and aerospace. . As the application fields of power batteries continue to expand, their market demand is also constantly expanding.
  • the electrode assembly in the cylindrical battery cell has long tabs extending outward relative to the end of the winding structure, and the long tabs extend continuously along the winding direction of the pole piece.
  • the long pole tab Before welding the long pole tab to the current collecting plate, the long pole tab needs to be bent and smoothed to form a structure in which the pole tabs overlap layer by layer from the outside to the inside.
  • the inventor's research has found that such long pole tabs have a certain curvature as the pole pieces are wound.
  • Such curved long pole tabs are prone to wrinkles when flattened, which can easily lead to rupture and damage of the pole tabs, and can also easily cause damage to the pole tabs.
  • embodiments of the present disclosure provide an electrode assembly, a battery cell, a battery, an electrical equipment, and a tab shaping device, which can improve the safety performance of the battery.
  • the electrode assembly of the embodiment of the present disclosure can be applied to various types of battery cells.
  • the battery cells may include lithium ion secondary batteries, lithium ion primary batteries, lithium sulfur batteries, sodium lithium ion batteries, sodium ion batteries or magnesium ion batteries, etc., which are not limited in the embodiments of the present disclosure.
  • the battery cell may be in the shape of a cylinder, a flat body, a rectangular parallelepiped or other shapes, and the embodiments of the present application are not limited to this. Battery cells are generally divided into cylindrical battery cells, prismatic battery cells and soft-pack battery cells according to the way of packaging, and the embodiments of the present application are not limited to this.
  • the battery cells of the embodiments of the present disclosure can be applied to various types of batteries. Batteries can be used to power electrical equipment such as vehicles, such as providing power for vehicle control or power for driving.
  • the battery may include a box and a battery module.
  • the box is used to provide accommodating space for the battery module, and the battery module is installed in the box.
  • the box body can be made of metal.
  • the battery module may include multiple battery cells connected in series, parallel or mixed.
  • the battery cell is the smallest unit that makes up the battery. Battery cells include electrode components that enable electrochemical reactions to occur.
  • the battery according to the embodiment of the present disclosure can be applied to various types of electrical devices using batteries.
  • Electric devices can be mobile phones, portable devices, laptops, battery cars, electric cars, ships, spacecraft, electric toys and power tools, etc.
  • spacecraft include airplanes, rockets, space shuttles and spaceships, etc.
  • electric toys include Fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys and electric airplane toys, etc.
  • Power tools include metal cutting power tools, grinding power tools, assembly power tools and railway power tools, such as , electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers.
  • the embodiments of the present invention do not impose special restrictions on the above-mentioned electrical devices.
  • FIG. 1 is a schematic structural diagram of some embodiments of an electrical device according to the present disclosure.
  • the description takes the electrical device as a vehicle as an example.
  • a battery 30 is disposed inside a vehicle 40 , and the battery 30 is disposed at the bottom, head, or tail of the vehicle 40 .
  • the battery 30 powers the vehicle 40 , for example, the battery 30 serves as an operating power source for the vehicle 40 .
  • the vehicle 40 may also include a controller and a motor, and the controller is used to control the battery 30 to provide power to the motor, for example, for starting, navigating, and driving the vehicle 40 to meet operating power requirements.
  • the battery 30 can not only be used as an operating power source of the vehicle 40 , but also can be used as a driving power source of the vehicle 40 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 40 .
  • FIG. 2A is a schematic structural diagram of some embodiments of a battery according to the present disclosure.
  • Figure 2B is a schematic structural diagram of the electrical connection of multiple battery cells in some embodiments of the battery according to the present disclosure.
  • the battery 30 includes a case and one or more battery cells 20 disposed in the case.
  • the box body includes a first box body 31 and a second box body 32.
  • the first box body 31 and the second box body 32 cover each other.
  • the first box body 31 and the second box body 32 jointly define a space for accommodating battery cells. 20 accommodation space.
  • the second box 32 may be a hollow structure with one end open to form a receiving cavity for accommodating the battery cells 20 .
  • the first box 31 may be a plate-like structure.
  • the first box 31 covers the open side of the second box 32 , so that the first box 31 and the second box 32 jointly define an accommodation space; the first box 31 and the second box 32 can also be open on one side to form an accommodation cavity for accommodating the battery cells 20 It has a hollow structure, and the opening side of the first box 31 is covered with the opening side of the second box 32 .
  • the box 20 formed by the first box 31 and the second box 32 can be in various shapes, such as a cylinder, a rectangular parallelepiped, etc.
  • FIG. 2A In order to facilitate observation of the plurality of battery cells 20 in the box 31 , only a part of the second box 32 is shown in FIG. 2A . Referring to FIG.
  • each battery cell 20 is electrically connected, such as in series, parallel or mixed connection, to achieve the required electrical performance parameters of the battery 30 .
  • a plurality of battery cells 20 are arranged in rows, and one or more rows of battery cells 20 can be arranged in the box as needed.
  • the battery cells 20 of the battery 30 may be arranged along at least one of the length direction and the width direction of the box. At least one row or column of battery cells 20 can be provided according to actual needs. If necessary, one or more layers of battery cells 20 may also be provided in the height direction of the battery 30 .
  • multiple battery cells 20 may be first connected in series, parallel, or mixed to form a battery module, and then multiple battery modules may be connected in series, parallel, or mixed to form a whole, and be accommodated in the box. In other embodiments, all the battery cells 20 are directly connected in series, parallel, or mixed together, and then the entirety of the battery cells 20 is accommodated in the box. In FIG. 2B , the electrode terminals 33 of the battery cells 20 are electrically connected to adjacent battery cells 20 through busbars 34 .
  • FIG. 3 is a schematic exploded structural diagram of a battery cell according to some embodiments of the present disclosure.
  • the battery cell 20 may include a housing assembly 21 and an electrode assembly 22 located within the housing assembly 21 .
  • Housing assembly 21 includes a housing 211 and an end cap 212 .
  • the housing 211 is a hollow structure with one side open.
  • the end cover 212 covers the opening of the housing 211 and forms a sealed connection to form a sealed space for accommodating the electrode assembly 22 .
  • the electrode assembly 22 is installed in the cavity of the housing 211.
  • the housing 211 and the end cover 212 may be independent components, and the end cover 212 is closed at the opening of the housing 211 to form the internal environment of the battery cell 20 .
  • the case 211 and the end cover 212 can also be integrated. Specifically, the case 211 and the end cover 212 can form a common connection surface before other components are put into the case. When it is necessary to package the battery cell 20 When it is inside, the end cover 212 is then closed with the housing 211 .
  • the housing 211 and the end cover 212 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiment of the present application.
  • the shell assembly is not limited to the above structure, and the shell assembly can also be other structures.
  • the shell assembly includes a shell and two end caps.
  • the shell is a hollow structure with openings on opposite sides, and an end cap.
  • the corresponding cover is closed at an opening of the housing and forms a sealed connection to form a sealed space for accommodating the electrode assembly and the electrolyte.
  • the electrode assembly 22 may include a main body portion 221 and a tab portion 222 extending from the main body portion 221 such that the tab portion 222 protrudes from an end of the main body portion 221 .
  • the electrode assembly 22 may include a positive electrode piece, a negative electrode piece, and a separator.
  • the electrode assembly 22 may be a rolled structure formed by rolling the positive electrode piece, the negative electrode piece and the isolation film.
  • the electrode assembly 22 may also be a stacked structure formed by a stacked arrangement of positive electrode sheets, negative electrode sheets, and isolation films.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer coated on two opposite sides of the positive electrode current collector.
  • the negative electrode sheet includes a negative electrode current collector and negative electrode active material layers coated on opposite sides of the negative electrode current collector.
  • the main body part 221 is the part of the electrode assembly 22 corresponding to the area where the pole piece is coated with the active material layer, and the pole tab part 222 is the part of the pole piece that is not coated with the active material layer.
  • the tab portion 222 can be divided into a positive tab portion and a negative tab portion.
  • the positive tab portion and the negative tab portion can be provided at both ends of the main body portion 221 or at one end of the main body portion 221 .
  • the battery cell 20 also includes an electrolyte and a current collecting member 23 .
  • the electrolyte is located in the housing and infiltrates into the electrode assembly 22 .
  • the housing assembly 21 includes an electrode lead-out part (such as a housing, an end cover, or an electrode terminal installed on the housing or end cover) for inputting or outputting electric energy; the electrode assembly 22 is accommodated in the housing assembly 21; a current collecting member 23 is accommodated in the housing assembly 21, and the current collecting member 23 is used to connect the electrode lead portion of the housing assembly 21 and the tab portion 222 of the electrode assembly 22, so that the tab portion 222 is electrically connected to the electrode lead portion.
  • the current collecting member 23 may be disc-shaped, called a current collecting plate, so as to be connected to the tab portion 222 at the end of the electrode assembly 22 .
  • the electrode assembly includes: a first pole piece 10A and a second pole piece 10B with opposite polarities, and a separator disposed between the first pole piece 10A and the second pole piece 10B. 10C.
  • the first pole piece 10A, the separator 10C and the second pole piece 10B are wound along the winding direction r to form the winding structure 100, for example, the second pole piece 10B and the separator formed along the radial direction of the winding mechanism 100 in Figure 4 are formed.
  • the first pole piece 10A can be a negative pole piece or a positive pole piece
  • the second pole piece 10B can be a positive pole piece or a negative pole piece with a polarity opposite to that of the first pole piece 10A.
  • the rolled structure 100 may form a cylindrical rolled structure after being rolled.
  • the casing adopted by the battery cell including the electrode assembly is a cylindrical casing structure.
  • the battery cell 10 mainly relies on the movement of metal ions between the positive electrode piece and the negative electrode piece to work.
  • the material of the diaphragm 10C may be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), or the like.
  • Figure 5 is a schematic diagram of the arrangement of the first pole piece, the second pole piece and the separator in some embodiments of the electrode assembly according to the present disclosure.
  • Figure 6 is a schematic structural diagram of some embodiments of an electrode assembly according to the present disclosure.
  • Figure 7 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure.
  • 8 is an expanded schematic diagram of a pole piece in some embodiments of an electrode assembly according to the present disclosure.
  • 9 is a schematic cross-sectional view of a pole piece in some embodiments of an electrode assembly according to the present disclosure.
  • At least one of the first pole piece 10A and the second pole piece 10B includes: current collectors 17A, 17B, active material layers 12A, 12B and pole tabs 11A ,11B.
  • the first pole piece 10A includes a current collector 17A, an active material layer 12A and a tab portion 11A.
  • the active material layer 12A is provided at least on the surface of the current collector adjacent to the separator 10C.
  • the second pole piece 10B is shown in FIGS. 5 , 8 and 9 .
  • the second pole piece 10B includes a current collector 17B, an active material layer 12B and a tab portion 11B.
  • the active material layer 12B is provided at least on the surface of the current collector adjacent to the separator 10C.
  • the negative electrode piece includes a current collector (ie, a negative electrode current collector), an active material layer 12A (ie, a negative electrode active material layer), and a tab portion 11A (ie, a negative electrode tab portion).
  • the active material layer 12A is coated on the surface of the current collector.
  • the negative electrode piece may also include an insulating layer 13A (such as a ceramic insulating layer, etc.) covering the surface of the current collector and located on the side of the active material layer 12A adjacent to the tab portion 11A.
  • the insulating layer 13A can prevent burrs on the cut edges of the anode pole from piercing the separator and causing a short circuit with the cathode pole.
  • the tab portion 11A is connected to one side of the current collector extending in the winding direction r.
  • the tab portion 11A has two areas, which are a continuous area 15A close to the active material layer and a spacing area 14A away from the active material layer.
  • the spacing area 14A includes a plurality of tabs arranged at intervals along the winding direction r. 16A.
  • the material of the negative electrode current collector can be copper, and the negative electrode active material layer can be made of graphite or silicon.
  • the tab portion 11A may be welded to the side of the current collector.
  • the tab portion 11A may also be formed by die-cutting the current collector.
  • the positive electrode piece includes a current collector (ie, a positive electrode current collector), an active material layer 12B (ie, a positive electrode active material layer), and a tab portion 11B (ie, a cathode tab portion).
  • the active material layer 12B is coated on the surface of the current collector.
  • the tab portion 11B is connected to one side of the current collector extending in the winding direction r.
  • the tab portion 11B has two areas, which are a continuous area 15B close to the active material layer and a spacing area 14B away from the active material layer.
  • the spacing area 14B includes a plurality of tabs arranged at intervals along the winding direction r. 16B.
  • the material of the cathode current collector can be aluminum, and the cathode active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganate.
  • the tab portion 11B can be welded to the side of the current collector.
  • the tab portion 11B may be formed by die-cutting the current collector.
  • the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B protrude from the end of the winding structure 100 and can be extruded respectively.
  • the indenter bends and flattens it, for example, it can be kneaded or smoothed, and the flattened tab part is welded to the current collecting member (such as the current collecting plate 230 in FIG. 7 ).
  • the two ends of the winding structure 100 are respectively provided with tab portions 11A and 11B.
  • the tab portions 11A and 11B are respectively smoothed or flattened and then welded to the current collecting plate 230 . .
  • the tab portions 11A and 11B are provided with continuous areas 15A and 15B and spacing areas 14A and 14B.
  • the spacing areas 14A and 14B include a plurality of tabs 16A and 16B arranged at intervals along the winding direction r. These tabs 16A and 16B can be formed by die-cutting and other processes. By setting the continuous areas 15A and 15B, a certain distance can be provided between the tabs 16A and 16B and the current collectors 17A and 17B, thereby avoiding the possibility of collecting the tabs during die-cutting.
  • the active material coating layer on the fluids 17A, 17B peels off.
  • the pole tabs 11A and 11B are flattened, since the bending strength of the interval regions 14A and 14B is significantly lower than the bending strength of the continuous regions 15A and 15B, the interval regions 14A and 14B can be bent and flattened.
  • the continuous areas 15A and 15B do not have obvious yielding bends, which can prevent the end faces of the tabs from being too close to the diaphragm 10C, causing burns to the diaphragm 10C when welding the flattened tabs 11A and 11B.
  • the pole tabs 16A and 16B located at the ends of the winding structure 100 can be flattened. Reduce the occurrence of wrinkles, thereby minimizing the rupture damage of the pole tabs 16A and 16B caused by the wrinkles of the pole tabs 16A and 16B.
  • the wrinkles and protrusions of the pole tabs 16A and 16B are inserted into the pole piece layer to damage the pole piece or cause the pole piece to be damaged. Problems such as short circuits, and when the spaced tabs 16A and 16B are flattened and overlap each other, a tighter dense layer can be formed, which can avoid the problem of solder penetration in subsequent welding and improve the welding yield.
  • the axis of the winding structure 100 is X.
  • the height before the pole lug is not bent is h0, and the height before the pole lug is not bent is h1.
  • the two satisfy: 0.25 ⁇ h1/h0 ⁇ 1.
  • h1/h0 may equal 0.25, 0.35, 0.45, 0.55, 0.65, 0.75, 0.85, or 0.95.
  • h1/h0 is not limited to this.
  • h1 ⁇ h0 is satisfied.
  • the final state of the tab is to be bent and flattened to facilitate connection with the current collecting plate.
  • the height h0 of the tab part and the height h1 of the tab part defined in this embodiment are the heights before the tab parts 16A and 16B are bent. It can also be said that the height of the tab part and the tab part 16A are , original height of 16B.
  • h0 and h1 can be measured before the pole tabs 16A and 16B of the pole piece are not bent.
  • Figure 6 and Figure 7 it is also possible to By straightening the pole tabs 11A and 11B in the winding structure 100, h0 and h1 can be measured conveniently.
  • the size of the tab portion of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the tab portion 11A of the first pole piece 10A may satisfy the above size, or it may
  • the tab portion 11B of the second pole piece 10B may satisfy the above dimensions, or the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B may both satisfy the above dimensions.
  • the height h0 of the pole part reflects the extended size of the pole part in the direction perpendicular to the side of the current collector; the height h1 of the pole part is the height of the separation area. In the same way, the height h1 of the pole part reflects the length of the pole part along the direction. The extended dimension of the tab in the direction perpendicular to the side of the current collector.
  • the height of the tabs in the separation area is insufficient, and the thickness of the dense layer formed after the tabs are flattened is insufficient, which may easily lead to problems such as welding penetration; if h1/h0 ⁇ 1, the height of the tab is greater than or equal to the entire tab.
  • the tab is cut, it is easy to cause the active material coating to fall off.
  • welding the flattened tab it is easy to burn the diaphragm.
  • the height relationship between the tab portion and the tab disclosed in this embodiment can not only ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, but also can improve the shedding of the active material coating layer caused by the tab slitting. problems and the problem of scalding the diaphragm when welding the pole lug.
  • the height h0 of the pole part before the pole is bent and the height h1 before the pole is bent satisfy: 0.4 ⁇ h1/h0 ⁇ 0.8.
  • h1/h0 may equal 0.4, 0.5, 0.6, 0.7, 0.8.
  • At least part of the pole lug is bent and flattened relative to the current collector.
  • the maximum distance from the bending line S to the top (free end) of the pole lug 16A, 16B is h2, that is, The height of the bent part is h2; in the axial direction of the winding structure 100, the height of the tab before it is bent is h1; h1 and h2 satisfy: 0.3 ⁇ h2/h1 ⁇ 1.
  • h2/h1 may equal 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.
  • h2/h1 may also be greater than 1, that is, the continuous area of the pole lug may also undergo yield bending.
  • the size of the tab portion of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the tab portion 11A of the first pole piece 10A may satisfy the above size, or it may
  • the tab portion 11B of the second pole piece 10B may satisfy the above dimensions, or the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B may both satisfy the above dimensions.
  • the bent and flattened part of the tab is also the part used for welding with the current collecting member (for example, the current collecting plate 20).
  • the height h2 of the bent part of the tab affects the yield of subsequent welding.
  • the height of the bending part is insufficient, resulting in insufficient thickness of the dense layer formed, which cannot meet the welding conditions, and may easily lead to problems such as welding penetration; if h2/h1>1, Then the height of the bent part is greater than the height before the tabs are bent, that is, the continuous area will also be bent. At this time, the thickness of the dense layer formed by flattening will not increase significantly, but will increase due to the slits between the tabs. Being completely compressed, it will adversely affect the electrolyte wetting performance.
  • the dimensional relationship between the tab and the bent part disclosed in this embodiment can not only ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, but also improve the electrolyte infiltration performance, so that the electrolysis cycle and power performance can be improved. improve.
  • the winding structure 100 is a cylindrical winding structure
  • the diameter of the central tube of the winding structure 100 is d
  • the arrow pointing in the winding direction (r) is the starting end.
  • d is the circumferential diameter of the pole piece layer corresponding to the first tab of the pole tabs 11A and 11B along the winding direction (r) in the cylindrical winding structure 100, that is, the diameter corresponding to the pole tab of the innermost ring of the winding structure.
  • the minimum diameter is d
  • the width of the pole lug is l, 0.7 ⁇ l/d ⁇ 2.
  • the width l of the pole lug reflects the size of the pole lug along the winding direction r.
  • 1/d may equal 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.
  • the size of the tab of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the tab 16A of the first pole piece 10A may satisfy the above size, or the size of the tab of the second pole piece 10B may satisfy the above formula.
  • the pole tab 16B of the pole piece 10B meets the above dimensions, or the pole tab 16A of the first pole piece 10A and the pole tab 16B of the second pole piece 10B may both meet the above dimensions.
  • the relationship between the tab width and the diameter of the innermost ring of the winding structure disclosed in this embodiment can ensure that the density of the dense layer formed after the tab is flattened meets the welding conditions, and at the same time can avoid the tab turning when the bare cell is wound. Loss of quality caused by folding, tearing, etc.
  • the maximum distance between adjacent tabs is g
  • the width of the tabs is l
  • g/l may equal 0.05, 0.10, 0.15, or 0.2.
  • the size of the tab of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the tab 16A of the first pole piece 10A may satisfy the above size, or the size of the tab of the second pole piece 10B may satisfy the above formula.
  • the pole tab 16B of the pole piece 10B meets the above dimensions, or the pole tab 16A of the first pole piece 10A and the pole tab 16B of the second pole piece 10B may both meet the above dimensions.
  • the width of the tabs is too small and the distance between tabs is too large, resulting in insufficient thickness of the dense layer formed after flattening, which easily affects the welding yield.
  • the relationship between the width of the tabs and the spacing between the tabs disclosed in this embodiment can ensure that the thickness of the dense layer formed after the tabs are flattened meets the welding conditions, thereby improving the welding quality.
  • the height h0 of the pole lug before the pole lug is not bent satisfies: 3mm ⁇ h0 ⁇ 8mm
  • the height h1 before the pole lug is not bent satisfies: 1mm ⁇ h1 ⁇ 8mm
  • the height h2 of the bent part of the tab satisfies: 1mm ⁇ h2 ⁇ 8mm.
  • h0 may equal 3mm, 4mm, 5mm, 6mm, 7mm, 8mm.
  • h1 can be equal to 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm.
  • h2 can be equal to 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm.
  • the size of the tab portion of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the tab portion 11A of the first pole piece 10A may satisfy the above size, or it may be
  • the tab portion 11B of the second pole piece 10B may satisfy the above dimensions, or the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B may both satisfy the above dimensions.
  • the size design of the tab portion, tab, and bending portion disclosed in this embodiment can make the tabs overlap each other to form a denser tab layer when flattened, so that The probability of laser welding penetration is significantly reduced, which improves the welding quality and avoids problems such as the active material coating layer falling off and affecting the infiltration of the electrolyte.
  • the height h0 of the pole lug before the pole lug is not bent satisfies: 4mm ⁇ h0 ⁇ 7mm
  • the height h1 before the pole lug is not bent satisfies: 2mm ⁇ h1 ⁇ 7mm
  • the height h2 of the bent part of the tab satisfies: 2mm ⁇ h2 ⁇ 7mm.
  • the size of the tab portion of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • h0 may equal 4mm, 5mm, 6mm, 7mm.
  • h1 can be equal to 2mm, 3mm, 4mm, 5mm, 6mm, 7mm.
  • h2 can be equal to 2mm, 3mm, 4mm, 5mm, 6mm, 7mm.
  • the size design of the tab portion, tab, and bending portion disclosed in this embodiment can make the tab layer formed by overlapping tabs during flattening more dense. It is excellent, which significantly reduces the probability of laser welding penetration, making it more effective in improving welding quality, preventing the active material coating layer from falling off, and avoiding affecting electrolyte infiltration.
  • FIG. 10 is an expanded schematic view of the pole piece in other embodiments of the electrode assembly according to the present disclosure. As shown in FIG. 10 , according to some embodiments of the present application, the tabs 16A and 16B of the pole pieces 10A and 10B are arranged obliquely relative to one side of the current collector extending along the winding direction.
  • At least one of the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B is tilted.
  • the pole tabs 16A of the first pole piece 10A can be tilted, or the pole tabs 16A of the first pole piece 10A can be tilted.
  • the pole tab 16B of the second pole piece 10B may be tilted, or the pole tab 16A of the first pole piece 10A and the pole tab 16B of the second pole piece 10B may both be tilted.
  • pole tabs extend vertically relative to the sides of the current collector.
  • the pole tabs do not extend vertically, but extend obliquely at a certain angle relative to the sides of the current collector.
  • the tabs of the pole piece extend obliquely relative to the side of the current collector, which can further reduce the intensity of the tabs in the interval area, making it easier for the tabs to be squeezed and flattened, which is beneficial to improving the strength of the dense layer formed after the tabs are flattened. Density and thickness, improving welding yield.
  • the inclination angle ⁇ of the tabs 16A and 16B satisfies: 45° ⁇ 90°.
  • ⁇ may equal 45°, 55°, 65°, 75°, 85°.
  • the inclination angle of at least one of the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B satisfies the above conditions.
  • it can be the inclination angle of the pole tabs 16A of the first pole piece 10A.
  • the inclination angle of the tab 16B of the second pole piece 10B may satisfy the above condition, or it may be the inclination angle of the tab 16A of the first pole piece 10A and the inclination angle of the tab 16B of the second pole piece 10B. All meet the above conditions.
  • the inventor of the present application found that when the inclination angle of the pole tab is less than 45°, the bending strength of the pole tab cannot be effectively reduced, and instead the pole tab is easily folded and damaged.
  • the inclination angle ⁇ of the tab disclosed in this embodiment can effectively reduce the bending strength of the tab, making it easier for the tab to be squeezed and flattened, and can effectively prevent the tab from turning over during winding and/or flattening. Folding and breakage issues.
  • Figure 11 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure. As shown in FIG. 11 , according to some embodiments of the present application, the inclination direction of the pole tabs 16A and 16B in the pole pieces 10A and 10B is opposite to the winding direction r of the pole pieces 10A and 10B.
  • At least one of the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B is inclined and the tilt direction is opposite to the winding direction r.
  • the first pole piece shown in FIG. 10 The pole tab 16A of the pole piece 10A and the pole tab 16B of the second pole piece 10B are both inclined, and both tilt directions are opposite to the winding direction r.
  • the tilt direction of the pole tab is opposite to the direction of winding the pole piece.
  • the pole tab is not easy to be folded or damaged, which can improve the yield of the winding structure.
  • the bent portions of the tabs 16A and 16B are bent and flattened by the rotational extrusion of the extrusion head 1000.
  • the extrusion head 1000 rotates along the rotation direction o to rotate the poles.
  • the bent parts of the ears 16A and 16B are smoothed or smoothed, and the inclination direction of the pole ears 16A and 16B is consistent with the rotation direction o of the extrusion head 1000.
  • At least one of the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B is inclined and the tilt direction is consistent with the rotation direction o of the extrusion head 1000.
  • the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B are shown to be inclined, and their inclination directions are consistent with the rotation direction o of the extrusion head 1000 .
  • the tilting direction of the tabs 16A and 16B is consistent with the rotation direction o of the extrusion head 1000, which can avoid damage to the tabs 16A and 16B during flattening, especially the tabs 16A and 16B at the outer ring and the end of the winding structure 100, which can improve the winding.
  • the yield of the wound structure 100 is consistent with the rotation direction o of the extrusion head 1000, which can avoid damage to the tabs 16A and 16B during flattening, especially the tabs 16A and 16B at the outer ring and the end of the winding structure 100, which can improve the winding.
  • the rotation direction o of the extrusion head 1000 is opposite to the winding direction r of the winding structure, and the inclination direction of the tabs 16A and 16B is consistent with the rotation direction o of the extrusion head 1000. And it is opposite to the winding direction r of the winding structure.
  • the pole tabs 16A and 16B can be prevented from being folded and damaged when the pole pieces 10A and 10B are wound, and the pole tabs 16A and 16B can be prevented from being damaged when the pole tabs 16A and 16B are flattened, thus making the winding structure good.
  • the rate is improved.
  • FIG. 12 is an expanded schematic view of the pole piece in other embodiments of the electrode assembly according to the present disclosure.
  • the side of the tabs 160A and 160B located at the end of the winding structure near the tail end is provided with a bevel Q formed by corner cutting.
  • the corners of the end tabs 160A and 160B close to the tail end can be directly cut off, so that the tail end of the tab forms a hypotenuse Q.
  • At least one of the tabs 160A of the first pole piece 10A at the end of the winding structure and the tabs 160B of the second pole piece 10B at the end of the winding structure is provided with a bevel Q, for example, it can be the third One pole piece 10A is provided with a bevel Q on the pole tab 160A at the end of the winding structure, or the second pole piece 10B is provided with a bevel Q on the pole tab 160B at the end of the winding structure, or the first pole piece
  • the pole tab 160A of 10A at the end of the winding structure and the pole tab 160B of the second pole piece 10B at the end of the winding structure are both provided with a bevel Q.
  • the end of the tab is die-cut so that the corner of the tail end is cut off, which can effectively improve this problem.
  • At least part of the hypotenuse Q of the tabs 160A and 160B located at the end of the winding structure is arc-shaped.
  • arc-shaped cutting is used to die-cut the corners of the tabs 160A and 160B at the ends of the pole pieces to form an arc-shaped bevel edge Q.
  • At least one of the pole tabs 160A of the first pole piece 10A at the end of the winding structure and the pole tabs 160B of the second pole piece 10B at the end of the winding structure is provided with an arc-shaped bevel Q, for example,
  • the first pole piece 10A is provided with an arc-shaped hypotenuse Q on the pole tab 160A at the end of the winding structure, or the second pole piece 10B is provided with an arc-shaped hypotenuse Q on the pole tab 160B at the end of the winding structure.
  • the pole tab 160A of the first pole piece 10A at the end of the winding structure and the pole tab 160B of the second pole piece 10B at the end of the winding structure are both provided with arc-shaped bevels Q.
  • hypotenuse formed by die-cutting at the corner of the pole lug is not limited to an arc shape, and may also be a straight shape, for example.
  • a tab shaping device is also provided. As shown in FIG. 11 , the tab shaping device includes an extrusion head 1000 .
  • the extrusion head 1000 is used to smooth the tabs 16A and 16B in the electrode assembly of any of the above embodiments, so that at least part of the tabs 16A and 16B are bent relative to the current collector and flattened.
  • the bent portions of the tabs 16A and 16B are bent and flattened by rotating and extruding the extrusion head 1000 .
  • the tabs 16A, 16B are arranged obliquely relative to one side of the current collector extending along the winding direction r. As shown in FIG. 11 , the extrusion head 1000 rotates along the rotation direction o to flatten or smooth the bent portions of the tabs 16A and 16B.
  • the rotation direction o of the extrusion head 1000 is configured to be in line with the directions of the tabs 16A and 16B. The tilt direction is consistent.
  • the rotation direction o of the extrusion head 1000 is consistent with the tilt direction of the tabs 16A and 16B, which can avoid damage to the tabs 16A and 16B during flattening, especially the tabs 16A and 16B at the outer ring and the end of the winding structure 100, which can improve the winding.
  • the yield of the wound structure 100 is consistent with the tilt direction of the tabs 16A and 16B, which can avoid damage to the tabs 16A and 16B during flattening, especially the tabs 16A and 16B at the outer ring and the end of the winding structure 100, which can improve the winding.
  • the tab shaping device provided by the present disclosure may also include other structures, such as a driving mechanism for driving the extrusion head, which is not limited in this embodiment.
  • a battery cell which includes the electrode assembly as in any of the preceding embodiments.
  • FIG. 2B shows a schematic diagram of the connection structure of multiple battery cells 20 , where each battery cell 20 includes an electrode assembly as in any of the previous embodiments.
  • the electrode assembly 22 adopts the electrode assembly of any of the aforementioned embodiments. Battery cells using the aforementioned electrode components have better performance, such as being safer and having higher product yields.
  • the tab is bent relative to the current collector and flattened, the maximum distance from the bending line to the top of the tab is h2, and the winding structure is a cylindrical winding structure.
  • the electrode assembly also includes a current collecting plate. The current collecting plate is located on the side of the cylindrical winding structure connected to the pole lug, and is fixedly connected to the bent part of the pole lug by welding.
  • the winding structure 100 is a cylindrical winding structure.
  • the two ends of the winding structure 100 are respectively provided with tab portions 13A and 13B.
  • the tab portions 13A and 13B are respectively bent. After smoothing, it is welded with the collecting plate 230 .
  • reference numeral 231 indicates the welding area 231 on the current collecting plate 20 .
  • the thickness of the current collecting plate 20 is t1
  • the height of the bent portion of the tab is h2
  • t1 and h2 satisfy: 0.05 ⁇ t1/h2 ⁇ 0.2.
  • the size of the bent portion of the tab 16A of at least one of the first pole piece 10A and the second pole piece 10B satisfies the above formula.
  • the size of the bent portion of the tab 16A of the first pole piece 10A satisfies the above formula.
  • the above dimensions may be such that the bent portion of the tab 16B of the second pole piece 10B satisfies the above dimensions, or they may be the bent portion of the tab 16A of the first pole piece 10A and the bent portion of the tab 16B of the second pole piece 10B. 16B bending parts all meet the above dimensions.
  • the height of the bent part is too large, resulting in the thickness of the dense layer formed after the tab is flattened, which will lead to a reduction in battery capacity; if t1/h2> 0.2, the height of the bent part is too small, resulting in insufficient thickness of the dense layer formed after flattening, which does not meet the welding conditions and may easily lead to problems such as welding penetration.
  • the relationship between the height of the bent portion of the tab and the thickness of the current collecting plate disclosed in this embodiment can ensure that the thickness of the dense layer formed after the tab is flattened meets the welding conditions, and at the same time, the battery capacity can be increased.
  • a battery 30 is also provided, including the battery cell 20 of any of the foregoing embodiments.
  • the battery 30 using the aforementioned battery cells 20 has better performance, such as being safer and having a higher product yield rate.
  • an electrical device is also provided, including the battery 30 of any of the aforementioned embodiments.
  • the electrical device may be any of the aforementioned electrical devices that require the use of batteries, such as electrical equipment or energy storage equipment.
  • the electrical device in Figure 1 is a vehicle. Electrical devices using the aforementioned batteries have better performance, such as being safer and more reliable.
  • some embodiments of the present disclosure provide an electrode assembly, including: a first pole piece 10A and a second pole piece 10B with opposite polarities, and located between the first pole piece 10A and the second pole piece 10B. Diaphragm 10C.
  • the first pole piece 10A, the separator 10C and the second pole piece 10B are wound along the winding direction r to form the winding structure 100.
  • the first pole piece 10A is a negative pole piece
  • the second pole piece 10B is the same as the first pole piece 10A.
  • Positive pole piece with opposite polarity The rolled structure 100 forms a cylindrical rolled structure after being rolled.
  • the first pole piece 10A includes a current collector 17A (ie, a negative electrode current collector), an active material layer 12A (ie, a negative electrode active material layer), and a tab portion 11A (ie, a negative electrode tab portion). ), also includes an insulating layer 13A (such as a ceramic insulating layer, etc.) covering the surface of the current collector 17A and located on the side of the active material layer 12A adjacent to the tab portion 11A; the tab portion 11A is connected to the current collector 17A along the winding direction. On one side extending r, the tab portion 11A has a continuous area 15A close to the active material layer and a spacing area 14A away from the active material layer.
  • the spacing area 14A includes a plurality of tabs 16A spaced apart along the winding direction r.
  • the second pole piece 10B includes a current collector 17B (i.e., a positive electrode current collector), an active material layer 12B (i.e., a positive electrode active material layer), and a tab portion 11B (i.e., a positive electrode tab portion); the tab portion 11B is connected to the edge of the current collector 17B.
  • a current collector 17B i.e., a positive electrode current collector
  • an active material layer 12B i.e., a positive electrode active material layer
  • a tab portion 11B i.e., a positive electrode tab portion
  • the tab portion 11B is connected to the edge of the current collector 17B.
  • the tab portion 11B On one side extending in the winding direction r.
  • the tab portion 11B has a continuous area 15B close to the active material layer and a spacing area 14B away from the active material layer.
  • the spacing area 14B includes a plurality of tabs 16B arranged at intervals along the winding direction r.
  • the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B respectively extend from both ends of the winding structure 100 , and the tab 16A of the pole tab 11A
  • the tabs 16B and tabs 11B of the tabs 11B are respectively pressed and flattened by the extrusion head 1000, and the flattened tabs 16A and 16B are respectively welded to the current collecting plate 230.
  • the tab portion 11A of the first pole piece 10A and the tab portion 11B of the second pole piece 10B both meet the following size settings: as shown in Figure 8, in the axial direction of the winding structure, the tab portion is at the end of the tab.
  • the height h0 before bending, the height h1 before the tab is bent, and the height h2 of the part of the tab used for bending and flattening meet the following conditions: h0 satisfies 4mm ⁇ h0 ⁇ 7mm, h1 satisfies 2mm ⁇ h1 ⁇ 7mm, h2 satisfies 2mm ⁇ h2 ⁇ 7mm, and 0.25 ⁇ h1/h0 ⁇ 1, 0.3 ⁇ h2/h1 ⁇ 1.
  • the pole tabs 16A of the first pole piece 10A and the pole tabs 16B of the second pole piece 10B are both tilted, and the tilting methods meet the following conditions: the tilt direction is consistent with the winding direction of the winding structure.
  • the rotation direction r is opposite and consistent with the rotation direction o of the extrusion head 1000, and the tilt angle ⁇ satisfies 45° ⁇ 90°.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Connection Of Batteries Or Terminals (AREA)

Abstract

电极组件、电池单体、电池、用电设备和极耳整形装置。电极组件包括：极性相反的第一极片和第二极片以及设于第一极片和第二极片之间的隔膜，第一极片、隔膜和第二极片沿卷绕方向卷绕并形成卷绕结构；其中，第一极片和第二极片中的至少一个包括：集流体；活性物质层，至少设置在集流体邻近隔膜一侧的表面；和极耳部，连接在集流体沿卷绕方向延伸的一个侧边上，极耳部包括靠近活性物质层的连续区域和远离活性物质层的间隔区域，间隔区域包括沿卷绕方向间隔排布的多个极耳。

Description

电极组件、电池单体、电池、用电设备和极耳整形装置 技术领域
本申请涉及电池技术领域，尤其涉及一种电极组件、电池单体、电池、用电设备和极耳整形装置。
背景技术
可再充电电池单体，可以称为二次电池单体，是指在电池单体放电后可通过充电的方式使活性物质激活而继续使用的电池单体。可再充电电池单体广泛用于电子设备，例如手机、笔记本电脑、电瓶车、电动汽车、电动飞机、电动轮船、电动玩具汽车、电动玩具轮船、电动玩具飞机和电动工具等。
电极组件作为构成电池单体的关键部件，在其形成过程中存在着一些与极耳相关的电池性能问题或安全问题。
发明内容
本申请旨在至少解决现有技术中电极组件存在的技术问题之一。为此，本申请的一个目的在于提出一种电极组件、电池单体、电池、用电设备和极耳整形装置。
本申请第一方面的实施例提供一种电极组件，包括：极性相反的第一极片和第二极片以及设于第一极片和第二极片之间的隔膜，第一极片、隔膜和第二极片沿卷绕方向卷绕并形成卷绕结构；其中，第一极片和第二极片中的至少一个包括：集流体；活性物质层，至少设置在集流体邻近隔膜一侧的表面；和极耳部，连接在集流体沿卷绕方向延伸的一个侧边上，极耳部包括靠近活性物质层的连续区域和远离活性物质层的间隔区域，间隔区域包括沿卷绕方向间隔排布的多个极耳。
本申请实施例的技术方案中，极耳部设有连续区域和间隔区域，间隔区域包括沿卷绕方向间隔排布的多个极耳，这些极耳可通过模切等工艺形成，通过设置连续区域，可以使得极耳与集流体之间具有一定间隔，从而避免极耳分切时导致集流体上的活性物质涂覆层脱落，从而改善电池性能。
在一些实施例中，在卷绕结构的轴向上，极耳部在极耳未弯折之前的高度为h0，极耳未弯折之前的高度为h1，h0和h1满足：0.25≤h1/h0<1。
本实施例中公开的极耳部和极耳的高度关系，既可以保证在极耳压平后形成的致密层的厚度满足焊接条件，又可以改善由于极耳分切导致的活性物质涂覆层脱落的问题以及极耳部焊接时烫伤隔膜的问题。
在一些实施例中，0.4≤h1/h0≤0.8。
经过本申请发明人大量的实验分析发现，极耳部和极耳的高度关系满足0.4≤h1/h0≤0.8时，可以更好地兼顾致密层厚度的需求以及改善活性物质涂覆层脱落和避免焊接时烫伤隔膜的问题，能够更好地满足焊接和极耳分切条件，可以使得电极组件制备良率更优。
在一些实施例中，极耳的至少部分相对于集流体弯折并被压平，弯折线至极耳顶端的最大距离为h2，在卷绕结构的轴向上，极耳未弯折之前的高度为h1，h1和h2满足：0.3≤h2/h1≤1。
本实施例中公开的极耳和弯折部分的尺寸关系，既能保证在极耳压平后形成的致密层的厚度满足焊接条件，又能提高电解液浸润性能，使得电解的循环、功率性能得以提高。
在一些实施例中，卷绕结构为圆柱形卷绕结构，卷绕结构的中心筒直径为d，极耳的宽度为l，l和d满足：0.7≤l/d≤2。
本实施例中公开的极耳宽度和卷绕结构最内圈直径的关系，能够保证极耳压平后形成的致密层的致密性满足焊接条件，同时可以避免裸电芯卷绕时极耳翻折、撕裂等导致出现的优率损失。
在一些实施例中，极耳部中相邻极耳之间的最大间距为g，极耳的宽度为l，l和g满足：g/l≤0.2。
本实施例中公开的极耳宽度和极耳之间间距的关系，能够保证极耳压平后形成的致密层的厚度满足焊接条件，使得焊接质量得以提高。
在一些实施例中，在卷绕结构的轴向上，极耳部在极耳未弯折之前的高度h0满足：3mm≤h0≤8mm，和/或，极耳未弯折之前的高度h1满足：1mm≤h1≤8mm，和/或，极耳的至少部分相对于集流体弯折并被压平，弯折线至极耳顶端的最大距离为h2，h2满足：1mm≤h2≤8mm。
本实施例中公开的极耳部、极耳和弯折部分的尺寸设计，可以使得极耳压平时相互交叠形成更致密的致密层，使得激光焊穿的概率明显的降低，使得焊接质量得以提高，同时可以避免活性物质层脱落、影响电解液浸润等问题。
在一些实施例中，高度h0满足：4mm≤h0≤7mm，和/或，高度h1满足：2mm≤h1≤7mm，和/或，距离h2满足：2mm≤h2≤7mm。
经过本申请发明人大量的实验分析发现，本实施例中公开的极耳部、极耳和弯折部分的尺寸设计，可以使得极耳压平时相互交叠形成的致密层的致密性更优，使得激光焊穿的概率显著的降低，使得在提高焊接质量、避免活性物质层脱落、避免影响电解液浸润等方面的效果更好。
在一些实施例中，极耳相对于集流体沿卷绕方向延伸的一个侧边倾斜设置。
极片的极耳相对于集流体的侧边倾斜延伸，能够进一步降低间隔区域的极耳强度，使得极耳更容易被挤压压平，有利于提高极耳被压平后形成的致密层的致密性和厚度，改善焊接良率。
在一些实施例中，极耳的倾斜方向与卷绕方向相反。极耳倾斜的方向与卷绕极片的方向相反，在卷绕极片时，极耳不容易翻折，破损，可以提高卷绕结构的良率。
在一些实施例中，极耳的至少部分相对于集流体弯折并被压平，极耳的弯折部分通过挤压头的旋转挤压实现弯折，极耳的倾斜方向与挤压头的旋转方向一致。极耳倾斜的方向与挤压头的旋转方向一致，可以避免压平时损伤极耳，尤其卷绕结构外圈和收尾处的极耳，可以提高卷绕结构的良率。
在一些实施例中，极耳的倾斜角度θ满足：45°≤θ<90°。本实施例中公开的极耳的倾斜角度θ，可以有效降低极耳的弯折强度，使得极耳更容易被挤压压平，并且可以有效避免极耳在卷绕和/或压平时的翻折和破损问题。
在一些实施例中，位于卷绕结构收尾处的极耳靠近尾端的一侧设有通过角部切割所形成的斜边。
在卷绕极片收尾切断时，由于切断位置未知，间隔区域的最后的极耳有可能被切割从而出现宽度过小的情况，进而导致该收尾处的极耳出现脱落、破裂、翘起等问题，为此，本实施例中，将收尾处的极耳模切使得其尾端的角部切除，可改善此问题。
在一些实施例中，斜边的至少一部分为弧形。
经过本申请发明人的实验分析发现，将极片收尾处的极耳模切形成弧形斜边，可以更加有效地避免尾部的极耳出现脱落、破裂、翘起等问题，进一步提高卷绕结构的良率。
本申请第二方面的实施例提供一种电池单体，其包括上述实施例中的电极组件。
在一些实施例中，极耳的至少部分相对于集流体弯折并被压平，弯折线至极耳顶端的最大距离为h2，卷绕结构为圆柱形卷绕结构，电池单体还包括：集流盘，位于圆柱形 卷绕结构连接极耳部的一侧，并与极耳的弯折部分通过焊接方式固定连接，集流盘的厚度为t1，t1和h2满足：0.05≤t1/h2≤0.2。
本实施例中公开的极耳弯折部分的高度和集流盘厚度的关系，能够保证极耳压平后形成的致密层的厚度满足焊接条件，同时可以使得电池容量得以提高。
本申请第三方面的实施例提供一种电池，其包括上述实施例中的电池单体。
本申请第四方面的实施例提供一种用电装置，其包括上述实施例中的电池，电池用于提供电能。
本申请第五方面的实施例提供一种极耳整形装置，包括挤压头，挤压头用于抚平根据上述任一项的电极组件中的极耳，使得极耳的至少部分相对于集流体弯折并被压平。
在一些实施例中，极耳相对于集流体沿卷绕方向延伸的一个侧边倾斜设置；挤压头的旋转方向被配置为与极耳的倾斜方向一致。
挤压头的旋转方向与极耳倾斜的方向一致，可以避免压平时损伤极耳，尤其卷绕结构外圈和收尾处的极耳，可以提高卷绕结构的良率。
上述说明仅是本申请技术方案的概述，为了能够更清楚了解本申请的技术手段，而可依照说明书的内容予以实施，并且为了让本申请的上述和其它目的、特征和优点能够更明显易懂，以下特举本申请的具体实施方式。
附图说明
在附图中，除非另外规定，否则贯穿多个附图相同的附图标记表示相同或相似的部件或元素。这些附图不一定是按照比例绘制的。应该理解，这些附图仅描绘了根据本申请公开的一些实施方式，而不应将其视为是对本申请范围的限制。
图1是根据本公开用电装置的一些实施例的结构示意图；
图2A是根据本公开电池的一些实施例的结构示意图；
图2B是根据本公开电池的一些实施例中多个电池单体电连接的结构示意图；
图3是根据本公开电池单体的一些实施例形成的电池单体的爆炸结构示意图；
图4是根据本公开电极组件的一些实施例形成的卷绕结构的截面示意图；
图5是根据本公开电极组件的一些实施例中第一极片、第二极片和隔膜的结构示意图；
图6是根据本公开电极组件的一些实施例的结构示意图；
图7是根据本公开电极组件的另一些实施例的结构示意图；
图8是根据本公开电极组件的一些实施例中极片的展开示意图；
图9是根据本公开电极组件的一些实施例中极片的截面示意图；
图10是根据本公开电极组件的另一些实施例中极片的展开示意图；
图11是根据本公开电极组件的另一些实施例的结构示意图；
图12是根据本公开电极组件的另一些实施例中极片的展开示意图。
附图标记说明：
10A：第一极片；10B：第二极片；10C：隔膜；100：卷绕结构；
11A，11B，222：极耳部；12A，12B：活性物质层；13A：绝缘层；
17A，17B：集流体；14A，14B：间隔区域；15A，15B：连续区域；
16A，16B：极耳；1000：挤压头；20：电池单体；21：外壳组件；
211：壳体；212：端盖；22：电极组件；221：主体部；23：集流构件；
230：集流盘；231：焊接区域；30：电池；31：第一箱体；32：第二箱体；
33：电极端子；34：汇流排；40：车辆。
具体实施方式
下面将结合附图对本申请技术方案的实施例进行详细的描述。以下实施例仅用于更加清楚地说明本申请的技术方案，因此只作为示例，而不能以此来限制本申请的保护范围。
除非另有定义，本文所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同；本文中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本申请；本申请的说明书和权利要求书及上述附图说明中的术语“包括”和“具有”以及它们的任何变形，意图在于覆盖不排他的包含。
在本申请实施例的描述中，技术术语“第一”“第二”等仅用于区别不同对象，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量、特定顺序或主次关系。在本申请实施例的描述中，“多个”的含义是两个以上，除非另有明确具体的限定。
在本文中提及“实施例”意味着，结合实施例描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其它实施例互斥的独立的或备选的实施例。本领域技术人员显式地和隐式地理解的是，本文所描述的实施例可以与其它实施例相结合。
在本申请实施例的描述中，术语“和/或”仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本文中字符“/”，一般表示前后关联对象是一种“或”的关系。
在本申请实施例的描述中，术语“多个”指的是两个以上(包括两个)，同理，“多组”指的是两组以上(包括两组)，“多片”指的是两片以上(包括两片)。
在本申请实施例的描述中，技术术语“中心”、“纵向”、“横向”、“长度”、“宽度”、“厚度”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”、“内”、“外”、“顺时针”、“逆时针”、“轴向”、“径向”、“周向”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本申请实施例和简化描述，而不是指示或暗示所指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请实施例的限制。
在本申请实施例的描述中，除非另有明确的规定和限定，技术术语“安装”、“相连”“连接”、“固定”等术语应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或成一体；也可以是机械连接，也可以是电连接；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通或两个元件的相互作用关系。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请实施例中的具体含义。
目前，从市场形势的发展来看，动力电池的应用越加广泛。动力电池不仅被应用于水力、火力、风力和太阳能电站等储能电源系统，而且还被广泛应用于电动自行车、电动摩托车、电动汽车等电动交通工具，以及军事装备和航空航天等多个领域。随着动力电池应用领域的不断扩大，其市场的需求量也在不断地扩增。
在一些相关技术中，圆柱形电池单体中的电极组件具有相对于卷绕结构的端部外伸的长极耳，长极耳沿极片的卷绕方向连续延伸。在将长极耳与集流盘进行焊接之前，需要将长极耳折弯抚平以形成极耳从外到内逐层交叠的结构。经发明人研究发现，这种长极耳随着极片的卷绕而具有一定的曲率，这种弯曲的长极耳在压平时容易出现皱褶，从而容易导致极耳的破裂损伤，也容易因褶皱朝向极片插入而造成极片短路的风险，从而影响电池的安全性能。并且，这种卷绕成圆环状的长极耳具有较高的抗弯强度，受挤压溃缩时产生的形变很难保证连续且均匀，因此，被压平后的极耳叠层不够均匀，致密性较差，在与集流盘焊接时容易造成焊穿，对制造设备和工艺的挑战非常大。
基于以上考虑，本公开实施例提供一种电极组件、电池单体、电池、用电设备和极耳整形装置，能够提升电池的安全性能。
本公开实施例的电极组件可适用于各类电池单体。电池单体可以包括锂离子二次电池、锂离子一次电池、锂硫电池、钠锂离子电池、钠离子电池或镁离子电池等，本公开实施例对此并不限定。电池单体可呈圆柱体、扁平体、长方体或其它形状等，本申请实施例对此也不限定。电池单体一般按封装的方式分柱形电池单体、方形电池单体和软包电池单体，本申请实施例对此也不限定。
本公开实施例的电池单体可适用于各类电池。电池可用于车辆等用电设备的供电，例如给车辆提供操控用的电源或者驱动行驶用的电源。电池可包括箱体和电池模组，箱体用于为电池模组提供容纳空间，电池模组安装在箱体内。箱体可采用金属材质。电池模组可包括串联、并联或混联的多个电池单体。电池单体为组成电池的最小单元。电池单体包括能够发生电化学反应的电极组件。
本公开实施例的电池可适用于各类使用电池的用电装置。用电装置可以是手机、便携式设备、笔记本电脑、电瓶车、电动汽车、轮船、航天器、电动玩具和电动工具等等，例如，航天器包括飞机、火箭、航天飞机和宇宙飞船等，电动玩具包括固定式或移动式的电动玩具，例如，游戏机、电动汽车玩具、电动轮船玩具和电动飞机玩具等等，电动工具包括金属切削电动工具、研磨电动工具、装配电动工具和铁道用电动工具，例如，电钻、电动砂轮机、电动扳手、电动螺丝刀、电锤、冲击电钻、混凝土振动器和电刨。本发明实施例对上述用电装置不做特别限制。
图1是根据本公开用电装置的一些实施例的结构示意图。为了方便，以用电装置为车辆为例进行说明。参考图1，车辆40的内部设置有电池30，电池30设置于车辆40的底部或头部或尾部。电池30为车辆40供电，例如，电池30作为车辆40的操作电源。车辆40还可以包括控制器和马达，控制器用来控制电池30为马达供电，例如，用于车辆40的启动、导航和行驶时的工作用电需求。
在本申请一些实施例中，电池30不仅可以作为车辆40的操作电源，还可以作为车辆40的驱动电源，代替或部分地代替燃油或天然气为车辆40提供驱动动力。
图2A是根据本公开电池的一些实施例的结构示意图。图2B是根据本公开电池的一些实施例中多个电池单体电连接的结构示意图。参考图2A，在一些实施例中，电池30包括箱体以及设置于箱体中的一个或者多个电池单体20。箱体包括第一箱体31和第二箱体32，第一箱体31与第二箱体32相互盖合，第一箱体31和第二箱体32共同限定出用于容纳电池单体20的容纳空间。第二箱体32可以为一端开口以形成容纳电池单体20的容纳腔的空心结构，第一箱体31可以为板状结构，第一箱体31盖合于第二箱体32的 开口侧，以使第一箱体31与第二箱体32共同限定出容纳空间；第一箱体31和第二箱体32也可以是均为一侧开口的以形成容纳电池单体20的容纳腔的空心结构，第一箱体31的开口侧盖合于第二箱体32的开口侧。当然，第一箱体31和第二箱体32形成的箱体20可以是多种形状，比如，圆柱体、长方体等。为了便于观察箱体31内的多个电池单体20，图2A只显示了一部分第二箱体32。参考图2B，各个电池单体20之间电连接，比如串联、并联或者混联，以实现所需要的电池30的电性能参数。多个电池单体20成排设置，根据需要可以在箱体内设置一排或者多排电池单体20。
在一些实施例中，电池30的各电池单体20可以沿着箱体的长度方向和宽度方向中的至少一个排列。根据实际需要可设置至少一行或一列电池单体20。根据需要，还可以在电池30的高度方向，也可设置一层或者多层电池单体20。
在一些实施例中，多个电池单体20可先串联或并联或混联组成电池模块，然后多个电池模块再串联或并联或混联形成一个整体，并容纳于箱体内。在另一些实施例中，所有电池单体20直接串联或并联或混联在一起，再将所有电池单体20构成的整体容纳于箱体内。在图2B中，电池单体20的电极端子33通过汇流排(Busbar)34与相邻的电池单体20电连接。
图3是根据本公开一些实施例的电池单体的爆炸结构示意图。如图3所示，电池单体20可包括外壳组件21以及位于外壳组件21内的电极组件22。外壳组件21包括壳体211和端盖212。壳体211为一侧开口的空心结构，端盖212盖合于壳体211的开口处并形成密封连接，以形成用于容纳电极组件22的密封空间。电极组件22被装在壳体211的空腔中。
壳体211和端盖212可以是独立的部件，通过使端盖212盖合在壳体211的开口处以形成电池单体20的内部环境。不限地，也可以使壳体211和端盖212一体化，具体地，壳体211和端盖212可以在其他部件入壳前先形成一个共同的连接面，当需要封装电池单体20的内部时，再使端盖212盖合壳体211。壳体211和端盖212的材质可以是多种，比如，铜、铁、铝、不锈钢、铝合金、塑胶等，本申请实施例对此不作特殊限制。
可以理解的，外壳组件并不仅仅局限于上述结构，外壳组件也可以是其他结构，比如，外壳组件包括壳体和两个端盖，壳体为相对的两侧开口的空心结构，一个端盖对应盖合于壳体的一个开口处并形成密封连接，以形成用于容纳电极组件和电解质的密封空间。
电极组件22可以包括主体部221和极耳部222，极耳部222从主体部221延伸，使得极耳部222凸出于主体部221的端部。电极组件22可以包括正极极片、负极极片和隔离膜。电极组件22可以是由正极极片、负极极片和隔离膜通过卷绕形成的卷绕式结构。电极组件22也可以是由正极极片、负极极片和隔离膜通过层叠布置形成的层叠式结构。正极极片包括正极集流体和涂覆于正极集流体相对的两侧的正极活性物质层。负极极片包括负极集流体和涂覆于负极集流体相对的两侧的负极活性物质层。主体部221为电极组件22与极片涂覆有活性物质层的区域相对应的部分，极耳部222为极片未涂覆活性物质层的部分。极耳部222可以分为正极极耳部和负极极耳部，正极极耳部和负极极耳部可以设置于主体部221的两端，也可以设置于主体部221的一端。
如图3所示，电池单体20除了包括电极组件22和外壳组件21，还包括电解液和集流构件23，电解液位于壳体内，浸润电极组件22内。外壳组件21包括用于输入或输出电能的电极引出部(例如壳体、端盖，或者是安装在壳体或端盖上的电极端子)；电极组件22容纳于外壳组件21内；集流构件23容纳于外壳组件21内，集流构件23用于连接外壳组件21的电极引出部和电极组件22的极耳部222，以使极耳部222与电极引出部电连接。例如，在一些实施例中，集流构件23可以为圆盘状，称之为集流盘，以便于与电极组件22端部的极耳部222相连。
图4是根据本公开电极组件的一些实施例形成的卷绕结构的截面示意图。参考图4，根据本申请的一些实施例，电极组件包括：极性相反的第一极片10A和第二极片10B，以及设于第一极片10A和第二极片10B之间的隔膜10C。第一极片10A、隔膜10C和第二极片10B沿卷绕方向r卷绕并形成卷绕结构100，例如形成图4中沿卷绕机构100的径向形成的第二极片10B、隔膜10C、第一极片10A、隔膜10C……的层叠结构。第一极片10A可以为负极极片或正极极片，第二极片10B为与第一极片10A极性相反的正极极片或负极极片。卷绕结构100可在卷绕后形成圆柱形卷绕结构。相应地，包括该电极组件的电池单体所采用的壳体为圆柱壳体结构。
电池单体10主要依靠金属离子在正极极片和负极极片之间移动来工作。隔膜10C的材质可以为PP(polypropylene，聚丙烯)或PE(polyethylene，聚乙烯)等。
图5是根据本公开电极组件的一些实施例中第一极片、第二极片和隔膜的设置示意图。图6是根据本公开电极组件的一些实施例的结构示意图。图7是根据本公开电极组件的另一些实施例的结构示意图。图8是根据本公开电极组件的一些实施例中极片的展开示意图。图9是根据本公开电极组件的一些实施例中极片的截面示意图。
参考图5、图8和图9，在一些实施例中，第一极片10A和第二极片10B中的至少一个包括：集流体17A、17B、活性物质层12A、12B和极耳部11A、11B。以图8和图9是第一级片10A为例，如图5、图8和图9中所示，第一极片10A包括集流体17A、活性物质层12A和极耳部11A。活性物质层12A至少设置在集流体邻近隔膜10C一侧的表面。以图8和图9是第二级片10B为例，如图5、图8和图9中所示，第二极片10B包括集流体17B、活性物质层12B和极耳部11B。活性物质层12B至少设置在集流体邻近隔膜10C一侧的表面。
以第一极片10A为负极极片为例，负极极片包括集流体(即负极集流体)、活性物质层12A(即负极活性物质层)和极耳部11A(即负极极耳部)。活性物质层12A涂覆于集流体的表面。以图5为例，负极极片还可以包括覆盖在集流体的表面，且位于活性物质层12A邻近极耳部11A一侧的绝缘层13A(例如陶瓷绝缘层等)。绝缘层13A可防止阳极极片被切割的边缘上的毛刺刺穿隔膜而与阴极极片发生短路。
极耳部11A连接在集流体沿卷绕方向r延伸的一个侧边上。极耳部11A具有两个区域，这两个区域分别为靠近活性物质层的连续区域15A和远离活性物质层的间隔区域14A，间隔区域14A包括沿卷绕方向r间隔排布的多个极耳16A。负极集流体的材料可以为铜，负极活性物质层可以为石墨或硅等。在一些实施例中，极耳部11A可以焊接在集流体的侧边。极耳部11A也可以通过对集流体的模切来形成。
以第二极片10B为正极极片为例，正极极片包括集流体(即正极集流体)、活性物质层12B(即正极活性物质层)和极耳部11B(即正极极耳部)。活性物质层12B涂覆于集流体的表面。
极耳部11B连接在集流体沿卷绕方向r延伸的一个侧边上。极耳部11B具有两个区域，这两个区域分别为靠近活性物质层的连续区域15B和远离活性物质层的间隔区域14B，间隔区域14B包括沿卷绕方向r间隔排布的多个极耳16B。以锂离子电池为例，正极集流体的材料可以为铝，正极活性物质层可以为钴酸锂、磷酸铁锂、三元锂或锰酸锂等。在一些实施例中，极耳部11B可以焊接在集流体的侧边。极耳部11B也可以通过对集流体的模切来形成。
如图6和图7所示，电极组件中，第一极片10A的极耳部11A和第二极片10B的极耳部11B从卷绕结构100的端部伸出，并分别可以通过挤压头使其弯折并被压平，例如可以采用揉平或者抚平，压平后的极耳部与集流构件(例如图7中的集流盘230)进行 焊接。例如在图7中，卷绕结构100的两端分别设有极耳部11A和极耳部11B，极耳部11A和极耳部11B分别在抚平或揉平后与集流盘230进行焊接。
参考图5-图7，极耳部11A、11B设有连续区域15A、15B和间隔区域14A、14B，间隔区域14A、14B包括沿卷绕方向r间隔排布的多个极耳16A、16B，这些极耳16A、16B可通过模切等工艺形成，通过设置连续区域15A、15B，可以使得极耳16A、16B与集流体17A、17B之间具有一定间隔，从而避免极耳模切时导致集流体17A、17B上的活性物质涂覆层脱落。
而且，在压平极耳部11A、11B时，由于间隔区域14A、14B的抗弯强度明显低于连续区域15A、15B的抗弯强度，因此，可以使得间隔区域14A、14B被弯折压平时连续区域15A、15B没有明显的屈服弯折，从而可以避免极耳部的端面距离隔膜10C过近，以致于对压平后的极耳部11A、11B进行焊接时烫伤隔膜10C。
并且，通过在极片10A、10B沿卷绕方向r延伸的侧边设置间隔排布的多个极耳16A、16B，可以使位于卷绕结构100端部的极耳16A、16B在被压平时减少皱褶的出现，从而尽量消除因极耳16A、16B皱褶所带来的极耳16A、16B破裂损伤、极耳16A、16B皱褶凸起插入极片层而损伤极片或导致极片短路等问题，而且，间隔设置的极耳16A、16B被压平时相互交叠可以形成更紧密的致密层，可以避免后续焊接出现焊穿的问题，使得焊接良率得以提高。
根据本申请的一些实施例，如图6、图7和图8所示，卷绕结构100的轴线为X，在卷绕结构100的轴向上，即轴线X的延伸方向上，极耳部在极耳未弯折之前的高度为h0，极耳未弯折之前的高度为h1，两者满足：0.25≤h1/h0<1。
例如，在一些实施例中，h1/h0可以等于0.25、0.35、0.45、0.55、0.65、0.75、0.85或者0.95。
当然，h1/h0的数值范围不限于此，例如，在其他实施例中，只要满足h1<h0即可。
可以理解的是，在电极组件中，极耳的最终状态是被弯折压平，以便于与集流盘连接。如图8所示，本实施例中限定的极耳部的高度h0和极耳的高度h1均是在极耳16A、16B未弯折之前的高度，也可以说是极耳部和极耳16A、16B的原始高度。在一些实施例中，以图8为例，可以在极片的极耳16A、16B未弯折之前进行测量h0和h1，在另一些实施例中，以图6和图7为例，也可以通过将卷绕结构100中的极耳部11A、11B捋直，以便于测量h0和h1。
本实施例中，第一极片10A和第二极片10B中的至少一个的极耳部的尺寸满足上述公式，例如，可以是第一极片10A的极耳部11A满足上述尺寸，也可以是第二极片10B的极耳部11B满足上述尺寸，或者，也可以是第一极片10A的极耳部11A和第二极片10B的极耳部11B均满足上述尺寸。
极耳部的高度h0体现了在与集流体的侧边相垂直的方向上极耳部的延展尺寸；极耳的高度h1即是间隔区域的高度，同理，极耳的高度h1体现了沿垂直于集流体的侧边的方向上极耳的延展尺寸。
经过本申请发明人的研究发现，若h1/h0<0.25，则间隔区域的极耳高度不足，极耳被压平后形成的致密层厚度不足，容易导致焊穿等问题；若h1/h0≥1，则极耳高度大于或等于整个极耳部，极耳分切时容易造成活性物质涂覆层脱落，对压平后的极耳部进行焊接时还容易烫伤隔膜。本实施例中公开的极耳部和极耳的高度关系，既可以保证在极耳压平后形成的致密层厚度满足焊接条件，又可以改善由于极耳分切导致的活性物质涂覆层脱落的问题以及极耳部焊接时烫伤隔膜的问题。
根据本申请的一些实施例，极耳部在极耳未弯折之前的高度h0以及极耳未弯折之前的高度h1满足：0.4≤h1/h0≤0.8。
例如，在一些实施例中，h1/h0可以等于0.4、0.5、0.6、0.7、0.8。
经过本申请发明人大量的实验分析发现，极耳部和极耳的高度关系满足0.4≤h1/h0≤0.8时，可以更好地兼顾致密层厚度的需求以及改善活性物质涂覆层脱落和避免焊接时烫伤隔膜的问题，能够更好地满足焊接和极耳分切条件，可以使得电极组件制备良率更优。
根据本申请的一些实施例，极耳的至少部分相对于集流体弯折并被压平，如图8所示，弯折线S至极耳16A、16B顶端(自由端)的最大距离为h2，即弯折部分的高度为h2；在卷绕结构100的轴向上，极耳未弯折之前的高度为h1；h1与h2满足：0.3≤h2/h1≤1。
例如，在一些实施例中，h2/h1可以等于0.3、0.4、0.5、0.6、0.7、0.8、0.9或者1。
当然，在实际应用中，h2/h1的数值范围不限于此，例如，在其他实施例中，h2/h1也可能大于1，即极耳部的连续区域也可能出现屈服弯折。
本实施例中，第一极片10A和第二极片10B中的至少一个的极耳部的尺寸满足上述公式，例如，可以是第一极片10A的极耳部11A满足上述尺寸，也可以是第二极片10B 的极耳部11B满足上述尺寸，或者，也可以是第一极片10A的极耳部11A和第二极片10B的极耳部11B均满足上述尺寸。
极耳被弯折压平的部分，也是用于与集流构件(例如集流盘20)焊接的部分，极耳弯折部分的高度h2影响着后续焊接的良率。
经过本申请发明人的研究发现，若h2/h1＜0.3，弯折部分的高度不足，导致形成的致密层厚度不足，不能满足焊接条件，容易导致焊穿等问题；若h2/h1＞1，则弯折部分的高度大于极耳未弯折之前的高度，即连续区域也会出现弯折，此时压平形成的致密层的厚度不会明显增加，反而会由于极耳之间的狭缝被完全压缩，对电解液浸润性能造成不良影响。本实施例中公开的极耳和弯折部分的尺寸关系，既能保证极耳压平后形成的致密层的厚度满足焊接条件，又能提高电解液浸润性能，使得电解的循环、功率性能得以提高。
如图6所示，根据本申请的一些实施例，卷绕结构100为圆柱形卷绕结构，卷绕结构100的中心筒直径为d，以卷绕方向(r)的箭头指向为起始端，d为极耳部11A、11B沿卷绕方向(r)的第一个极耳在圆柱形卷绕结构100中对应的极片层的圆周直径，即卷绕结构最内圈的极耳对应的最小直径为d，极耳的宽度为l，0.7≤l/d≤2。极耳的宽度l体现了极耳沿卷绕方向r上的尺寸。
例如，在一些实施例中，l/d可以等于0.7、0.8、0.9、1、1.1、1.2、1.3、1.4、1.5、1.6、1.7、1.8、1.9或者2。
本实施例中，第一极片10A和第二极片10B中至少一个的极耳的尺寸满足上述公式，例如，可以是第一极片10A的极耳16A满足上述尺寸，也可以是第二极片10B的极耳16B满足上述尺寸，或者，也可以是第一极片10A的极耳16A和第二极片10B的极耳16B均满足上述尺寸。
经过本申请发明人的研究发现，若l/d＜0.7，极耳宽度过小，在模切极耳后极片收卷时，以及裸电芯卷绕时极耳容易翻折、撕裂，导致出现优率损失甚至安全问题；若l/d＞2，极耳宽度过大，无法有效降低极耳强度(尤其在裸电芯内圈和中圈)，无法有效提升极耳压平后形成的致密层的紧密程度，容易导致焊接不良。本实施例中公开的极耳宽度和卷绕结构最内圈直径的关系，能够保证极耳压平后形成的致密层的致密性满足焊接条件，同时可以避免裸电芯卷绕时极耳翻折、撕裂等导致出现的优率损失。
如图8所示，根据本申请的一些实施例，相邻极耳之间的最大间距为g，极耳的宽度为l，g/l≤0.2。
例如，在一些实施例中，g/l可以等于0.05、0.10、0.15或者0.2。
本实施例中，第一极片10A和第二极片10B中至少一个的极耳的尺寸满足上述公式，例如，可以是第一极片10A的极耳16A满足上述尺寸，也可以是第二极片10B的极耳16B满足上述尺寸，或者，也可以是第一极片10A的极耳16A和第二极片10B的极耳16B均满足上述尺寸。
经过本申请发明人的研究发现，若g/l＞0.2时，极耳宽度过小，极耳之间的间距过大，导致压平后形成的致密层厚度不足，容易影响焊接良率。本实施例中公开的极耳宽度和极耳之间间距的关系，能够保证极耳压平后形成的致密层的厚度满足焊接条件，使得焊接质量得以提高。
如图8所示，根据本申请的一些实施例，极耳部在极耳未弯折之前的高度h0满足：3mm≤h0≤8mm，和/或，极耳未弯折之前的高度h1满足：1mm≤h1≤8mm，和/或，极耳的弯折部分的高度h2满足：1mm≤h2≤8mm。
例如，在一些实施例中，h0可以等于3mm、4mm、5mm、6mm、7mm、8mm。h1可以等于1mm、2mm、3mm、4mm、5mm、6mm、7mm、8mm。h2可以等于1mm、2mm、3mm、4mm、5mm、6mm、7mm、8mm。
本实施例中，第一极片10A和第二极片10B中至少一个的极耳部的尺寸满足上述公式，例如，可以是第一极片10A的极耳部11A满足上述尺寸，也可以是第二极片10B的极耳部11B满足上述尺寸，或者，也可以是第一极片10A的极耳部11A和第二极片10B的极耳部11B均满足上述尺寸。
经过本申请发明人的大量实验分析发现，本实施例中公开的极耳部、极耳、和弯折部分的尺寸设计，可以使得压平时极耳相互交叠形成更致密的极耳层，使得激光焊穿的概率明显的降低，使得焊接质量得以提高，同时可以避免活性物质涂覆层脱落、影响电解液浸润等问题。
如图8所示，根据本申请的一些实施例，极耳部在极耳未弯折之前的高度h0满足：4mm≤h0≤7mm，和/或，极耳未弯折之前的高度h1满足：2mm≤h1≤7mm,和/或，极耳的弯折部分的高度h2满足：2mm≤h2≤7mm。本实施例中，第一极片10A和第二极片10B中至少一个的极耳部的尺寸满足上述公式。
例如，在一些实施例中，h0可以等于4mm、5mm、6mm、7mm。h1可以等于2mm、3mm、4mm、5mm、6mm、7mm。h2可以等于2mm、3mm、4mm、5mm、6mm、7mm。
经过本申请发明人大量的实验分析发现，本实施例中公开的极耳部、极耳、和弯折部分的尺寸设计，可以使得压平时极耳相互交叠形成的极耳层的致密性更优，使得激光焊穿的概率显著的降低，使得在提高焊接质量、避免活性物质涂覆层脱落、避免影响电解液浸润等方面的效果更好。
图10是根据本公开电极组件的另一些实施例中极片的展开示意图。如图10所示，根据本申请的一些实施例，极片10A、10B的极耳16A、16B相对于集流体沿卷绕方向延伸的一个侧边倾斜设置。
本实施例中，第一极片10A的极耳16A和第二极片10B的极耳16B中至少一个是倾斜设置的，例如，可以是第一极片10A的极耳16A倾斜设置，也可以是第二极片10B的极耳16B倾斜设置，或者，也可以是第一极片10A的极耳16A和第二极片10B的极耳16B均倾斜设置。
常规的极耳是相对于集流体的侧边垂直延伸的，本公开实施例中，极耳不是垂直延伸，而是相对于集流体的侧边呈一定夹角倾斜延伸。极片的极耳相对于集流体的侧边倾斜延伸，能够进一步降低间隔区域的极耳强度，使得极耳更容易被挤压压平，有利于提高极耳被压平后形成的致密层的致密性和厚度，改善焊接良率。
如图10所示，根据本申请的一些实施例，极耳16A、16B的倾斜角度θ满足：45°≤θ<90°。
例如，在一些实施例中，θ可以等于45°、55°、65°、75°、85°。
本实施例中，第一极片10A的极耳16A和第二极片10B的极耳16B中至少一个的倾斜角度满足上述条件，例如，可以是第一极片10A的极耳16A的倾斜角度满足上述条件，也可以是第二极片10B的极耳16B的倾斜角度满足上述条件，或者，也可以是第一极片10A的极耳16A和第二极片10B的极耳16B的倾斜角度均满足上述条件。
经过本申请发明人大量的实验分析发现，当极耳的倾斜角小于45°时，不能有效降低极耳的弯折强度，并且反而使得极耳容易翻折、破损。本实施例中公开的极耳的倾斜角度θ，可以有效降低极耳的弯折强度，使得极耳更容易被挤压压平，并且可以有效避免极耳在卷绕和/或压平时的翻折和破损问题。
图11是根据本公开电极组件的另一些实施例的结构示意图。如图11所示，根据本申请的一些实施例，极片10A、10B中极耳16A、16B的倾斜方向与极片10A、10B的卷绕方向r相反。
本实施例中，第一极片10A的极耳16A和第二极片10B的极耳16B中至少一个为倾斜设置且倾斜方向与卷绕方向r相反，例如，图10中所示的第一极片10A的极耳16A和第二极片10B的极耳16B均倾斜设置且两者倾斜方向均与卷绕方向r相反。
极耳倾斜的方向与卷绕极片的方向相反，在卷绕极片时，极耳不容易翻折，破损，可以提高卷绕结构的良率。
如图11所示，根据本申请的一些实施例，极耳16A、16B的弯折部分通过挤压头1000的旋转挤压实现弯折压平，挤压头1000沿旋转方向o旋转以将极耳16A、16B的弯折部分揉平或抚平，极耳16A、16B的倾斜方向与挤压头1000的旋转方向o一致。
本实施例中，第一极片10A的极耳16A和第二极片10B的极耳16B中至少一个为倾斜设置且倾斜方向与挤压头1000的旋转方向o一致，例如，图11中所示的第一极片10A的极耳16A和第二极片10B的极耳16B均倾斜设置且两者倾斜方向与挤压头1000的旋转方向o一致。
极耳16A、16B倾斜的方向与挤压头1000的旋转方向o一致，可以避免压平时损伤极耳16A、16B，尤其卷绕结构100外圈和收尾处的极耳16A、16B，可以提高卷绕结构100的良率。
在一些实施例中，以图11为例，挤压头1000沿旋转方向o与卷绕结构的卷绕方向r相反，极耳16A、16B的倾斜方向与挤压头1000的旋转方向o一致，并与卷绕结构的卷绕方向r相反。这样，既可以避免在卷绕极片10A、10B时极耳16A、16B翻折、破损，又可以避免在压平极耳16A、16B时损伤极耳16A、16B，可以使得卷绕结构的良率得以提升。
图12是根据本公开电极组件的另一些实施例中极片的展开示意图。如图12所示，根据本申请的一些实施例，位于卷绕结构收尾处的极耳160A、160B靠近尾端的一侧设有通过角部切割所形成的斜边Q。例如，可以在卷绕极片10A、10B收尾切断时，直接将收尾处的极耳160A、160B靠近尾端的角切除，以使得该极耳的尾端形成一条斜边Q。
本实施例中，第一极片10A在卷绕结构收尾处的极耳160A和第二极片10B在卷绕结构收尾处的极耳160B中至少一个设有斜边Q，例如，可以是第一极片10A在卷绕结构收尾处的极耳160A设有斜边Q，也可以是第二极片10B在卷绕结构收尾处的极耳160B设有斜边Q，或者，第一极片10A在卷绕结构收尾处的极耳160A和第二极片10B在卷绕结构收尾处的极耳160B均设有斜边Q。
如图11所示，在卷绕极片收尾切断时，由于切断位置未知，间隔区域的最后的极耳16A、16B有可能被切割从而出现宽度过小的情况，进而导致该收尾处的极耳出现脱落、破裂、翘起等问题。为此，本实施例中，将收尾处的极耳模切使得其尾端的角部切除，可有效改善此问题。
如图12所示，根据本申请的一些实施例，位于卷绕结构收尾处的极耳160A、160B的斜边Q至少一部分为弧形。例如，在一些实施例中，利用弧形切割的方式将极片收尾处的极耳160A、160B角部模切，以形成弧形斜边Q。
本实施例中，第一极片10A在卷绕结构收尾处的极耳160A和第二极片10B在卷绕结构收尾处的极耳160B中至少一个设有弧形斜边Q，例如，可以是第一极片10A在卷绕结构收尾处的极耳160A设有弧形斜边Q，也可以是第二极片10B在卷绕结构收尾处的极耳160B设有弧形斜边Q，或者，第一极片10A在卷绕结构收尾处的极耳160A和第二极片10B在卷绕结构收尾处的极耳160B均设有弧形斜边Q。
经过本申请发明人的实验分析发现，将极片收尾处的极耳模切形成弧形斜边，可以更加有效地避免尾部的极耳出现脱落、破裂、翘起等问题，进一步提高卷绕结构的良率。
当然，极耳角部模切形成的斜边不限于是弧形，例如也可以是直线形。
根据本公开的一些实施例，还提供了一种极耳整形装置。如图11所示，极耳整形装置包括挤压头1000。挤压头1000用于抚平上述任一实施例的电极组件中的极耳16A、16B，以使得极耳16A、16B的至少部分相对于集流体弯折并被压平。
根据本公开的一些实施例，极耳16A、16B的弯折部分通过挤压头1000的旋转挤压实现弯折压平。
根据本公开的一些实施例，极耳16A、16B相对于集流体沿卷绕方向r延伸的一个侧边倾斜设置。如图11所示，挤压头1000沿旋转方向o旋转以将极耳16A、16B的弯折部分揉平或抚平，挤压头1000的旋转方向o被配置为与极耳16A、16B的倾斜方向一致。
挤压头1000的旋转方向o与极耳16A、16B倾斜的方向一致，可以避免压平时损伤极耳16A、16B，尤其卷绕结构100外圈和收尾处的极耳16A、16B，可以提高卷绕结构100的良率。
当然，本公开提供的极耳整形装置还可以包括其他结构，例如还包括用于驱动挤压头动作的驱动机构，本实施例对此不做限定。
根据本公开的一些实施例，还提供了一种电池单体，其包括如前述任一实施例的电极组件。例如图2B所示为多个电池单体20连接结构示意图，其中每个电池单体20包括如前述任一实施例的电极组件。或者例如，图3所示的电池单体20，其中的电极组件22采用前述任一实施例的电极组件。采用前述电极组件的电池单体具有更优的性能，例如更安全、产品良率更高等。
根据本申请的一些实施例，极耳的至少部分相对于所述集流体弯折并被压平，弯折线至极耳顶端的最大距离为h2，卷绕结构为圆柱形卷绕结构。电极组件还包括集流盘，集流盘位于圆柱形卷绕结构连接极耳部的一侧，并与极耳的弯折部分通过焊接方式固定连接。
例如在图7中，卷绕结构100为圆柱形卷绕结构，卷绕结构100的两端分别设有极耳部13A和极耳部13B，极耳部13A和极耳部13B分别在弯折抚平后与集流盘230进行焊接。以图7所示为例，标号231示出了集流盘20上的焊接区域231。
如图7所示，在一些实施例中，集流盘20的厚度为t1，极耳的弯折部分的高度为h2，t1与h2满足：0.05≤t1/h2≤0.2。
本实施例中，第一极片10A和第二极片10B中至少一个的极耳弯折部分的尺寸满足上述公式，例如，可以是第一极片10A的极耳16A弯折部分的尺寸满足上述尺寸，也可以是第二极片10B的极耳16B弯折部分的尺寸满足上述尺寸，或者，也可以是第一极片10A的极耳16A弯折部分和第二极片10B的极耳16B弯折部分均满足上述尺寸。
经过本申请发明人的研究发现，若t1/h2＜0.05，则弯折部分的高度过大，导致极耳压平后形成的致密层厚度过大，将导致电池容量降低；若t1/h2＞0.2，则弯折部分的高度过小，导致压平后形成的致密层厚度不足，不满足焊接条件，容易导致焊穿等问题。本实施例中公开的极耳弯折部分的高度和集流盘厚度的关系，能够保证极耳压平后形成的致密层的厚度满足焊接条件，同时可以使得电池容量得以提高。
如图2A所示，根据本公开的一些实施例，还提供了一种电池30，包括如前述任一实施例的电池单体20。采用前述电池单体20的电池30具有更优的性能，例如更安全、产品良率更高等。
如图1所示，根据本公开的一些实施例，还提供了一种用电装置，包括前述任一实施例的电池30。
用电装置可以是前述的任意一种需要使用到电池的用电装置，例如为用电设备或者储能设备。例如，图1中的用电装置为车辆。采用前述电池的用电装置具有更优的性能，例如更安全可靠。
如图4所示，本公开一些实施例提供的电极组件，包括：极性相反的第一极片10A和第二极片10B，以及设于第一极片10A和第二极片10B之间的隔膜10C。第一极片10A、隔膜10C和第二极片10B沿卷绕方向r卷绕并形成卷绕结构100，第一极片10A为负极极片，第二极片10B为与第一极片10A极性相反的正极极片。卷绕结构100在卷绕后形成圆柱形卷绕结构。
如图5、图8和图9所示，第一极片10A包括集流体17A(即负极集流体)、活性物质层12A(即负极活性物质层)和极耳部11A(即负极极耳部)，还包括覆盖在集流体17A的表面，且位于活性物质层12A邻近极耳部11A一侧的绝缘层13A(例如陶瓷绝缘层等)；极耳部11A连接在集流体17A沿卷绕方向r延伸的一个侧边上，极耳部11A具有靠近活性物质层的连续区域15A和远离活性物质层的间隔区域14A，间隔区域14A包括沿卷绕方向r间隔排布的多个极耳16A。
第二极片10B包括集流体17B(即正极集流体)、活性物质层12B(即正极活性物质层)和极耳部11B(即正极极耳部)；极耳部11B连接在集流体17B沿卷绕方向r延伸的一个侧边上。极耳部11B具有靠近活性物质层的连续区域15B和远离活性物质层的间隔区域14B，间隔区域14B包括沿卷绕方向r间隔排布的多个极耳16B。
如图6和图7所示，第一极片10A的极耳部11A和第二极片10B的极耳部11B分别从卷绕结构100的两端伸出，极耳部11A的极耳16A和极耳部11B的极耳16B分别被挤压头1000挤压压平，压平后的极耳16A和极耳16B分别与集流盘230焊接。
第一极片10A的极耳部11A和第二极片10B的极耳部11B均满足下述尺寸设置：如图8所示，在卷绕结构的轴向上，极耳部在极耳未弯折之前的高度h0，极耳未弯折之前的高度h1，以及极耳部用于弯折压平的部分的高度h2三者满足以下条件：h0满足4mm≤h0≤7mm，h1满足2mm≤h1≤7mm，h2满足2mm≤h2≤7mm，且0.25≤h1/h0<1，0.3≤h2/h1≤1。
并且，如图10和图11所示，第一极片10A的极耳16A和第二极片10B的极耳16B均倾斜设置，且倾斜方式均满足以下条件：倾斜方向与卷绕结构的卷绕方向r相反，且与挤压头1000的旋转方向o一致，倾斜角度θ满足45°≤θ<90°。
最后应说明的是：以上各实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述各实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分或者全部技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的范围，其均应涵盖在本申请的权利要求和说明书的范围当中。尤其是，只要不存在结构冲突，各个实施例中所提到的各项技术特征均可以任意方式组合起来。本申请并不局限于文中公开的特定实施例，而是包括落入权利要求的范围内的所有技术方案。

Claims (20)

  1. 一种电极组件，包括：极性相反的第一极片(10A)和第二极片(10B)以及设于所述第一极片(10A)和所述第二极片(10B)之间的隔膜(10C)，所述第一极片(10A)、所述隔膜(10C)和所述第二极片(10B)沿卷绕方向(r)卷绕并形成卷绕结构(100)；
    其中，所述第一极片(10A)和所述第二极片(10B)中的至少一个包括：
    集流体(17A；17B)；
    活性物质层(12A；12B)，至少设置在所述集流体(17A；17B)邻近所述隔膜(10C)一侧的表面；和
    极耳部(11A；11B)，连接在所述集流体(17A；17B)沿所述卷绕方向(r)延伸的一个侧边上，所述极耳部(11A；11B)包括靠近所述活性物质层(12A；12B)的连续区域(15A；15B)和远离所述活性物质层(12A；12B)的间隔区域(14A；14B)，所述间隔区域(14A；14B)包括沿卷绕方向(r)间隔排布的多个极耳(16A；16B)。
  2. 根据权利要求1所述的电极组件，其中，在所述卷绕结构(100)的轴向上，所述极耳部(11A；11B)在极耳(16A；16B)未弯折之前的高度为h0，所述极耳(16A；16B)未弯折之前的高度为h1，h0和h1满足：0.25≤h1/h0<1。
  3. 根据权利要求2所述的电极组件，其中，0.4≤h1/h0≤0.8。
  4. 根据权利要求1-3中任一项所述的电极组件，其中，所述极耳(16A；16B)的至少部分相对于所述集流体(17A；17B)弯折并被压平，弯折线(S)至极耳顶端的最大距离为h2，在所述卷绕结构(100)的轴向上，所述极耳(16A；16B)未弯折之前的高度为h1，h1和h2满足：0.3≤h2/h1≤1。
  5. 根据权利要求1-4中任一项所述的电极组件，其中，所述卷绕结构(100)为圆柱形卷绕结构，所述卷绕结构(100)的中心筒直径为d，所述极耳(16A；16B)的宽度为l，l和d满足：0.7≤l/d≤2。
  6. 根据权利要求1-5中任一项所述的电极组件，其中，所述极耳部(11A；11B)中相邻极耳(16A；16B)之间的最大间距为g，所述极耳(16A；16B)的宽度为l，l和g满足：g/l≤0.2。
  7. 根据权利要求1-6中任一项所述的电极组件，其中，在所述卷绕结构(100)的轴向上，所述极耳部(11A；11B)在极耳(16A；16B)未弯折之前的高度h0满足：3mm≤h0≤8mm，和/或，所述极耳(16A；16B)未弯折之前的高度h1满足：1mm≤h1≤8mm，
    和/或，所述极耳(16A；16B)的至少部分相对于所述集流体(17A；17B)弯折并被压平，弯折线(S)至极耳(16A；16B)顶端的最大距离h2满足：1mm≤h2≤8mm。
  8. 根据权利要求7所述的电极组件，其中，所述高度h0满足：4mm≤h0≤7mm，和/或，所述高度h1满足：2mm≤h1≤7mm，和/或，所述距离h2满足：2mm≤h2≤7mm。
  9. 根据权利要求1-8中任一项所述的电极组件，其中，所述极耳(16A；16B)相对于所述集流体(17A；17B)沿所述卷绕方向(r)延伸的一个侧边倾斜设置。
  10. 根据权利要求9所述的电极组件，其中，所述极耳(16A；16B)的倾斜方向与所述卷绕方向(r)相反。
  11. 根据权利要求9或10所述的电极组件，其中，所述极耳(16A；16B)的至少部分相对于所述集流体(17A；17B)弯折并被压平，所述极耳(16A；16B)的弯折部分通过挤压头(1000)的旋转挤压实现弯折，所述极耳(16A；16B)的倾斜方向与所述挤压头(1000)的旋转方向(o)一致。
  12. 根据权利要求9-11中任一项所述的电极组件，其中，所述极耳(16A；16B)的倾斜角度θ满足：45°≤θ<90°。
  13. 根据权利要求1-12中任一项所述的电极组件，其中，位于所述卷绕结构(100)收尾处的极耳(160A；160B)靠近尾端的一侧设有通过角部切割所形成的斜边(Q)。
  14. 根据权利要求13所述的电极组件，所述斜边(Q)的至少一部分为弧形。
  15. 一种电池单体，包括：根据权利要求1-14中任一项所述的电极组件。
  16. 根据权利要求15所述的电池单体，其中，
    所述极耳(16A；16B)的至少部分相对于所述集流体(17A；17B)弯折并被压平，弯折线(S)至极耳顶端的最大距离为h2，
    所述卷绕结构(100)为圆柱形卷绕结构，
    所述电池单体还包括：集流盘(230)，位于所述圆柱形卷绕结构(100)连接所述极耳部(11A；11B)的一侧，并与所述极耳(16A；16B)的弯折部分通过焊接方式固定连接，所述集流盘(230)的厚度为t1，t1和h2满足：
    0.05≤t1/h2≤0.2。
  17. 一种电池，包括根据权利要求15或16所述的电池单体。
  18. 一种用电装置，包括根据权利要求17所述的电池。
  19. 一种极耳整形装置，包括挤压头(1000)，所述挤压头(1000)用于抚平根据权利要求1-14中任一项所述的电极组件中的极耳(16A；16B)，使得所述极耳(16A；16B)的至少部分相对于所述集流体(17A；17B)弯折并被压平。
  20. 根据权利要求19所述的极耳整形装置，其中，
    所述极耳(16A；16B)相对于所述集流体(17A；17B)沿所述卷绕方向(r)延伸的一个侧边倾斜设置；
    所述挤压头(1000)的旋转方向(o)被配置为与所述极耳(16A；16B)的倾斜方向一致。
PCT/CN2022/117329 2022-09-06 2022-09-06 电极组件、电池单体、电池、用电设备和极耳整形装置 WO2024050697A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN202280089801.2A CN118556338A (zh) 2022-09-06 2022-09-06 电极组件、电池单体、电池、用电设备和极耳整形装置
PCT/CN2022/117329 WO2024050697A1 (zh) 2022-09-06 2022-09-06 电极组件、电池单体、电池、用电设备和极耳整形装置

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/117329 WO2024050697A1 (zh) 2022-09-06 2022-09-06 电极组件、电池单体、电池、用电设备和极耳整形装置

Publications (1)

Publication Number Publication Date
WO2024050697A1 true WO2024050697A1 (zh) 2024-03-14

Family

ID=90192700

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/117329 WO2024050697A1 (zh) 2022-09-06 2022-09-06 电极组件、电池单体、电池、用电设备和极耳整形装置

Country Status (2)

Country Link
CN (1) CN118556338A (zh)
WO (1) WO2024050697A1 (zh)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004319311A (ja) * 2003-04-17 2004-11-11 Shin Kobe Electric Mach Co Ltd 捲回式円筒型リチウムイオン電池
CN113193165A (zh) * 2021-05-28 2021-07-30 微宏动力系统（湖州）有限公司 极耳极片及卷绕电池
CN114156545A (zh) * 2021-10-22 2022-03-08 天津空间电源科技有限公司 一种阶梯式一体成型极耳卷绕式锂离子电池及其制备方法
CN217062176U (zh) * 2022-03-21 2022-07-26 珠海冠宇电池股份有限公司 一种极片和电池

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004319311A (ja) * 2003-04-17 2004-11-11 Shin Kobe Electric Mach Co Ltd 捲回式円筒型リチウムイオン電池
CN113193165A (zh) * 2021-05-28 2021-07-30 微宏动力系统（湖州）有限公司 极耳极片及卷绕电池
CN114156545A (zh) * 2021-10-22 2022-03-08 天津空间电源科技有限公司 一种阶梯式一体成型极耳卷绕式锂离子电池及其制备方法
CN217062176U (zh) * 2022-03-21 2022-07-26 珠海冠宇电池股份有限公司 一种极片和电池

Also Published As

Publication number Publication date
CN118556338A (zh) 2024-08-27

Similar Documents

Publication Publication Date Title
US11757161B2 (en) Battery cell, battery and electricity consuming device
WO2023240803A1 (zh) 正极极片、电极组件、电池单体、电池及用电设备
CN218769985U (zh) 电极组件、电池单体、电池、用电装置和极耳整形装置
WO2024093100A1 (zh) 电极极片、电极组件、电池单体、电池和用电设备
WO2023246134A1 (zh) 极片、电极组件、电池单体、电池及用电设备
CN212161993U (zh) 电极组件、电池、电池模块、电池组、使用电池的装置和电极组件的制造装置
CN114709572B (zh) 电极组件、电化学装置及用电设备
US20240222812A1 (en) Electrode plate, electrode assembly, battery, electric device, and manufacturing method for electrode plate
US20230223642A1 (en) Pressure relief apparatus, battery cell, battery, and electrical device
WO2023168954A1 (zh) 电芯、电芯的制造方法、电池单体、电池及用电设备
WO2024050697A1 (zh) 电极组件、电池单体、电池、用电设备和极耳整形装置
WO2023236346A1 (zh) 电极组件、电池单体、电池及用电装置
WO2023138416A1 (zh) 电池单体及其制作方法、电池、用电装置
CN201859918U (zh) 一种圆柱型锂离子电池
EP3940853B1 (en) Electrode assembly and related battery, device, manufacturing method and manufacturing device thereof
CN116014305A (zh) 电池单体、电池、用电装置及电池单体的制造方法
CN114503334A (zh) 电极组件及其相关电池、装置、制造方法和制造装置
CN219017703U (zh) 电极组件、电池单体、电池及用电装置
WO2024020766A1 (zh) 电池单体、电池、用电装置及电池单体的制造方法
CN220382158U (zh) 电极组件、电池单体、电池及用电设备
CN217719797U (zh) 电极组件、电池单体、电池以及用电装置
WO2024040503A1 (zh) 电极组件、制备方法、电池单体、电池及用电装置
WO2024031427A1 (zh) 极片、电极组件、电池单体、电池以及用电装置
WO2024087190A1 (zh) 极片、电极组件、二次电池及用电装置
WO2024092726A1 (zh) 电极组件、电池单体、电池和用电装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22957671

Country of ref document: EP

Kind code of ref document: A1