WO2023082290A1 - 电极组件及其制作方法、电池单体、电池和用电装置 - Google Patents

电极组件及其制作方法、电池单体、电池和用电装置 Download PDF

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Publication number
WO2023082290A1
WO2023082290A1 PCT/CN2021/130772 CN2021130772W WO2023082290A1 WO 2023082290 A1 WO2023082290 A1 WO 2023082290A1 CN 2021130772 W CN2021130772 W CN 2021130772W WO 2023082290 A1 WO2023082290 A1 WO 2023082290A1
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WIPO (PCT)
Prior art keywords
pole piece
electrode assembly
diaphragm
material layer
viscous
Prior art date
Application number
PCT/CN2021/130772
Other languages
English (en)
French (fr)
Inventor
张楠
鲁力
Original Assignee
宁德时代新能源科技股份有限公司
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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 EP21963736.0A priority Critical patent/EP4310978A1/en
Priority to KR1020237026636A priority patent/KR20230129034A/ko
Priority to CN202180090110.XA priority patent/CN116762184A/zh
Priority to PCT/CN2021/130772 priority patent/WO2023082290A1/zh
Priority to JP2023544308A priority patent/JP2024505849A/ja
Publication of WO2023082290A1 publication Critical patent/WO2023082290A1/zh

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    • 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
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/46—Separators, membranes or diaphragms characterised by their combination with electrodes
    • H01M50/461—Separators, membranes or diaphragms characterised by their combination with electrodes with adhesive layers between electrodes and 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H45/00—Folding thin material
    • B65H45/02—Folding limp material without application of pressure to define or form crease lines
    • B65H45/06—Folding webs
    • B65H45/10—Folding webs transversely
    • B65H45/101—Folding webs transversely in combination with laying, i.e. forming a zig-zag pile
    • B65H45/1015—Folding webs provided with predefined fold lines; Refolding prefolded webs, e.g. fanfolded continuous forms
    • 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
    • H01M10/04—Construction or manufacture in general
    • H01M10/0413—Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes
    • 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
    • H01M10/052—Li-accumulators
    • 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
    • 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
    • H01M10/0583—Construction or manufacture of accumulators with folded construction elements except wound ones, i.e. folded positive or negative electrodes or separators, e.g. with "Z"-shaped electrodes or separators
    • 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
    • H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
    • B65H2801/00—Application field
    • B65H2801/72—Fuel cell manufacture
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present application relates to the technical field of energy storage devices, in particular to an electrode assembly and a manufacturing method thereof, a battery cell, a battery and an electrical device.
  • the present application provides an electrode assembly and a manufacturing method thereof, a battery cell, a battery and an electrical device, which can reduce costs and improve production efficiency.
  • the first aspect of the embodiment of the present application provides an electrode assembly, including: a first pole piece, the first pole piece is coated with an active material layer and a viscous material layer on both sides along the thickness direction of the pole piece, and the active material layer and the viscous material layer on each side are The material layer is arranged side by side along the height direction of the pole piece; and the separator is arranged on both sides of the first pole piece along the thickness direction of the pole piece, and is stacked with the first pole piece; in the state where the electrode assembly is expanded, the first pole piece every The diaphragm on the side is a continuous integral structure, and the diaphragm is connected to the first pole piece through an adhesive substance layer.
  • the diaphragm is bonded to the first pole piece through the viscous substance layer, so that the positions of the diaphragm and the first pole piece are fixed without coating the viscous substance on the diaphragm.
  • Apply glue layer reduce cost and improve production efficiency.
  • the viscous material layer is coated on both ends of the first pole piece, and the active material layer is coated between the viscous material layers on both sides.
  • the viscous material layer is arranged on both ends of the first pole piece along the height direction of the pole piece, so that the end position of the first pole piece is bonded and fixed to the diaphragm, which can reduce the occurrence of folding or wrinkling of the diaphragm Danger, to ensure the insulation effect of the diaphragm.
  • one or more viscous material layers are arranged at intervals between the viscous material layers on both sides, and an active material layer is coated between two adjacent viscous material layers.
  • a viscous material layer is arranged between the viscous material layers on both sides, which can enhance the bonding effect between the diaphragm and the first pole piece, and the production cost is relatively low and the production efficiency is high.
  • a plurality of viscous material layers are arranged between the viscous material layers on both sides. While enhancing the bonding effect between the diaphragm and the first pole piece, the flatness between the diaphragm and the first pole piece can be improved, and the middle position of the first pole piece can be reduced. The corresponding risk of wrinkles in the separator will not lead to an increase in the overall thickness of the electrode assembly after lamination, and improve the quality of the electrode assembly.
  • the viscous substance layer has a width of 2-20 mm along the height direction of the pole piece, which can improve the bonding strength between the separator and the first pole piece along the height direction of the pole piece.
  • the thickness of the viscous substance layer along the thickness direction of the pole piece is greater than or equal to the thickness of the active material layer, so that when the diaphragm is attached to the first pole piece, it can ensure that the diaphragm is in contact with the viscous substance layer, so that the viscous substance layer Can play the role of bonding diaphragm.
  • the thickness of the viscous substance layer along the thickness direction of the pole piece is 25-120 ⁇ m.
  • the viscous substance layer is a hot-melt adhesive layer, and the hot-melt adhesive layer connects the separator and the first pole piece through thermal lamination.
  • the hot melt adhesive acts to generate viscosity, so that the diaphragm is bonded to the viscous material layer, thereby achieving the effect of bonding the diaphragm and the first pole piece.
  • the material of the adhesive layer is polypropylene.
  • Polypropylene can withstand the electrolyte, and the diaphragm can be bonded to the first pole piece under the action of thermal compounding at a temperature of 70-90°C.
  • the first pole piece includes a plurality of bent sections and a plurality of stacked first stacked sections, and each bent section connects two adjacent first stacked sections; along the thickness direction of the pole piece,
  • the bending section includes a thinning portion or a cutting portion to facilitate bending of the first pole piece.
  • the reduced thickness portion and the cut portion are used to guide the first pole piece to bend in the area of the reduced thickness portion when making the electrode assembly, so as to facilitate the lamination operation, which is beneficial to improve the bending position controllability and accuracy.
  • the first pole piece is an anode piece.
  • the anode piece is used as the first pole piece to be bonded to the diaphragm, which can reduce the risk of corrosion of the casing caused by powder falling of the anode active material material.
  • the electrode assembly further includes a second pole piece, opposite in polarity to the first pole piece; the second pole piece includes a plurality of second laminated segments, and in the stacked state of the electrode assembly, each second laminated segment is set Between two adjacent first lamination sections.
  • the formed electrode assembly can better meet the use requirements, and the electrical performance of the electrode assembly can be optimized.
  • the second aspect of the embodiment of the present application provides a method for manufacturing an electrode assembly, including the following steps: providing a first pole piece, coating an active material layer and a viscous material layer on both sides of the first pole piece along the thickness direction, and making the active material layer Adjacent to the viscous substance layer; providing a diaphragm, the diaphragm is arranged on both sides of the first pole piece along the thickness direction of the pole piece, and stacked with the first pole piece; the diaphragm is connected to the first pole piece through the viscous substance layer.
  • the adhesive layer is attached to the first pole piece through a thermally laminated membrane.
  • the step of providing the first pole piece includes: forming a plurality of thickness-reduced portions on the first pole piece by scoring or laser cleaning.
  • the manufacturing method of the electrode assembly further includes the following steps: laminating the separator and the first pole piece together, and bending at a plurality of thickness-reduced parts, so that the first pole piece has multiple bent sections and multiple Each first stacked section is stacked, and each bent section connects two adjacent first stacked sections.
  • the manufacturing method of the electrode assembly further includes providing a second pole piece, and disposing the second pole piece between adjacent first lamination segments that are stacked.
  • the third aspect of the embodiment of the present application provides a battery cell, which includes the electrode assembly of the first aspect, or an electrode assembly manufactured by the method for manufacturing the electrode assembly of the second aspect.
  • a fourth aspect of the embodiment of the present application provides a battery, including a plurality of battery cells according to the third aspect.
  • a fifth aspect of the embodiments of the present application provides an electric device, including the battery according to the fourth aspect, and the battery is used to provide electric energy.
  • Fig. 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application.
  • Fig. 2 is a schematic explosion diagram of a battery provided by some embodiments of the present application.
  • FIG. 3 is a schematic structural diagram of a battery module provided in an embodiment of the present application.
  • Fig. 4 is a schematic explosion diagram of a battery cell provided by some embodiments of the present application.
  • Fig. 5 is a cross-sectional view of an electrode assembly provided by some embodiments of the present application.
  • Fig. 6 is a schematic diagram of the expansion of the first pole piece and the diaphragm provided by some embodiments of the present application;
  • Fig. 7 is the A-A direction sectional view of Fig. 6;
  • Fig. 8 is a schematic diagram of the first pole piece in Fig. 6;
  • Fig. 9 is an A-A sectional view of other embodiments of Fig. 6;
  • Fig. 10 is a schematic diagram of the first pole piece in Fig. 9;
  • Figure 11 is an enlarged view of Part II in Figure 9;
  • Fig. 12 is a schematic diagram of the stacked first pole pieces of some embodiments of the present application.
  • Fig. 13 is an enlarged view of part I in Fig. 5;
  • Figure 14 is a cross-sectional view of an electrode assembly provided by another embodiment of the present application.
  • Fig. 15 is a schematic diagram of the first pole piece provided by other embodiments of the present application.
  • Fig. 16 is a schematic diagram of the connection structure of the first pole piece, the second pole piece and the diaphragm of the embodiment shown in Fig. 5;
  • FIG. 17 is a flowchart of a method for manufacturing an electrode assembly according to an embodiment of the present application.
  • 21-end cover assembly 211-electrode terminal, 212-end cover
  • “Plurality” in this application refers to two or more (including two).
  • 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, which are not limited in the embodiments of the present application.
  • the battery cell can be in the form of a cylinder, a flat body, a cuboid or other shapes, which is not limited in this embodiment of the present application.
  • Battery cells are generally divided into three types according to packaging methods: cylindrical battery cells, square battery cells and pouch battery cells, which are not limited in this embodiment of the present application.
  • the battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.
  • the battery mentioned in this application may include a battery module or a battery pack, and the like.
  • Batteries generally include a case for enclosing one or more battery cells. The box can prevent liquid or other foreign objects from affecting the charging or discharging of the battery cells.
  • the battery cell includes an electrode assembly and an electrolyte, and the electrode assembly is composed of a cathode sheet, an anode sheet, and a separator.
  • a battery cell primarily relies on the movement of metal ions between the cathode and anode tabs to function.
  • the cathode sheet includes a cathode current collector and a cathode active material layer, the cathode active material layer is coated on the surface of the cathode current collector, and the cathode current collector not coated with the cathode active material layer protrudes from the cathode collector coated with the cathode active material layer Fluid, the cathode current collector not coated with the cathode active material layer is used as the cathode tab.
  • the anode active material layer is coated on the surface of the anode current collector, the anode current collector not coated with the anode active material layer protrudes from the anode current collector coated with the anode active material layer, and the anode current collector not coated with the anode active material layer as an anode lug.
  • the number of cathode tabs is multiple and stacked together, and the number of anode tabs is multiple and stacked together.
  • the electrode assembly can be a wound structure or a laminated structure.
  • the wound electrode assembly is an electrode assembly formed by winding the cathode electrode sheet, the anode electrode sheet, and the separator between the cathode electrode sheet and the anode electrode sheet.
  • the laminated electrode assembly includes a plurality of single-piece cathode pole pieces and a plurality of single-piece anode pole pieces and a structure in which the diaphragm is alternately stacked and laminated, or a continuous integral pole piece (anode pole piece or Cathode electrode sheet) is laminated with the cathode electrode sheet in a zigzag shape after attaching a diaphragm on both sides along the thickness direction of the electrode sheet, thereby forming a laminated electrode assembly.
  • This kind of diaphragm completely covers the structure of the anode pole piece.
  • the diaphragm on both sides of the pole piece in the thickness direction is completely attached to the pole piece.
  • the pole piece will not shift and the pole piece will not contact the pole piece.
  • the safety of the battery ensures the full play of the battery capacity.
  • the diaphragm is attached to the pole piece by the adhesiveness of the adhesive layer of the diaphragm, but the cost of gluing the diaphragm as a whole is very high, resulting in an overall increase in the cost of making the electrode assembly, and the production efficiency of the overall gluing of the diaphragm is low.
  • the embodiment of the present application provides a technical solution.
  • the diaphragm does not need to be glued, and a glue layer is applied to the current collector on both sides of the active material layer of the pole piece along the height direction of the pole piece, and the glue layer on the diaphragm and the current collector Bonding, to achieve the attachment of the diaphragm to the pole piece, reduce costs and improve production efficiency.
  • the embodiments of the present application are described in detail below.
  • Electric devices can be vehicles, mobile phones, portable devices, notebook computers, ships, spacecraft, electric toys and electric tools, and so on.
  • Vehicles can be fuel vehicles, gas vehicles or new energy vehicles, and new energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles;
  • spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.;
  • electric toys include fixed Type or mobile electric toys, such as game consoles, electric car toys, electric boat toys and electric airplane toys, etc.;
  • electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, for example, Electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, electric planers, and more.
  • the embodiments of the present application do not impose special limitations on the above-mentioned electrical devices.
  • the device using a battery is taken as an example for description.
  • Fig. 1 is a schematic structural diagram of a vehicle 1 provided by some embodiments of the present application.
  • a battery 2 is provided inside a vehicle 1, and a battery 2 refers to a single physical module including one or more battery cells to provide higher voltage and capacity, for example, the one mentioned in this application
  • the battery 2 may include a battery module or a battery pack or the like.
  • the battery 2 can be arranged at the bottom or the head or the tail of the vehicle 1 .
  • the battery 2 can be used for power supply of the vehicle 1 , for example, the battery 2 can be used as an operating power source of the vehicle 1 .
  • the vehicle 1 may also include a controller 3 and a motor 4 , the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, for the starting, navigation and working power requirements of the vehicle 1 during driving.
  • the battery 2 can not only be used as an operating power source for the vehicle 1 , but can also be used as a driving power source for the vehicle 1 to provide driving power for the vehicle 1 instead of or partially replacing fuel oil or natural gas.
  • Fig. 2 is a schematic exploded view of a battery 2 provided by some embodiments of the present application.
  • the battery 2 includes a case body 5 and a battery cell 20 , and the battery cell 20 is accommodated in the case body 5 .
  • the box body 5 is used to accommodate the battery cells 20, and the box body 5 may have various structures.
  • the box body 5 may include a first box body part 51 and a second box body part 52, the first box body part 51 and the second box body part 52 cover each other, the first box body part 51 and the second box body part 51
  • the two box parts 52 jointly define an accommodating space 53 for accommodating the battery cells 21 .
  • the second box part 52 can be a hollow structure with an open end, and the first box part 51 can be a plate-shaped structure, and the first box part 51 covers the opening side of the second box part 52 to form an accommodating space.
  • the first casing part 51 and the second casing part 52 also all can be the hollow structure of one side opening, and the opening side of the first casing part 51 covers the opening of the second casing part 52 side to form a box body 5 with an accommodating space 53 .
  • the first box body part 51 and the second box body part 52 can be in various shapes, such as a cylinder, a cuboid, and the like.
  • a sealing member may also be provided between the first box body portion 51 and the second box body portion 52, such as sealant, sealing ring, etc. .
  • the first box part 51 covers the top of the second box part 52
  • the first box part 51 can also be called the upper box cover
  • the second box part 52 can also be called the lower box.
  • the plurality of battery cells 20 may be connected in series, in parallel or in parallel.
  • the mixed connection means that the plurality of battery cells 20 are both connected in series and in parallel.
  • a plurality of battery cells 20 can be directly connected in series or in parallel or mixed together, and then the whole composed of a plurality of battery cells 20 can be accommodated in the box body 5; of course, a plurality of battery cells 20 can also be connected in series first Or parallel or mixed connection to form a battery pack, and multiple battery packs are connected in series, parallel or mixed to form a whole, and accommodated in the box body 5 .
  • FIG. 3 is a schematic structural diagram of a battery module 200 provided in an embodiment of the present application.
  • the battery cells 20 may be arranged in groups for ease of installation, and each group of battery cells 20 constitutes a battery module 200 .
  • the battery 2 may include a plurality of battery modules 200, and these battery modules 200 may be connected in series, in parallel or in parallel.
  • FIG. 4 is a schematic exploded view of a battery cell 20 provided by some embodiments of the present application.
  • the battery cell 20 refers to the smallest component unit used to form the battery 2.
  • the battery cell 20 may include a lithium-ion secondary battery cell, a lithium-ion primary battery cell , a lithium-sulfur battery cell, a sodium-lithium-ion battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, etc., which are not limited in this embodiment of the present application.
  • the battery cell 20 may be flat, rectangular, or other shapes, which are not limited in the embodiment of the present application. For the convenience of description, the following embodiments all use the rectangular parallelepiped battery cell 20 as an example.
  • the battery cell 20 includes an end cap assembly 21 , an electrode assembly 22 and a casing 23 .
  • the casing 23 is used to accommodate the electrode assembly 22 in the casing 23 .
  • the shell 23 can be of various shapes and sizes. Specifically, the shape of the shell 23 can be determined according to the specific shape and size of one or more electrode assemblies 22 .
  • the housing 23 is a hollow cuboid. In other embodiments, the housing 23 may be cylindrical or other shapes.
  • One end of the casing 23 is an opening 231 , and the end cap assembly 21 covers the opening 231 and is connected with the casing 23 to form a closed cavity for placing the electrode assembly 22 .
  • the cavity may be filled with electrolyte.
  • the end cover assembly 21 includes an end cover 212, the end cover 212 is provided with an electrode terminal 211, the electrode assembly 22 is provided with a tab 221, and the electrode terminal 211 can be used for electrical connection with the tab 221 for use to output the electric energy of the battery cells 20 .
  • Each electrode terminal 211 may be correspondingly provided with a current collecting member, and the current collecting member may be located between the end cap 212 and the tab 221 so that the electrode terminal 211 and the tab 221 may be electrically connected through the current collecting member.
  • the end cap assembly 21 may also be provided with other functional components, for example, a pressure relief mechanism for releasing the internal pressure of the battery cell 20 when the internal pressure or temperature reaches a threshold value.
  • the housing 23 and the end cover 212 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy and the like.
  • FIG. 5 is a cross-sectional view of an electrode assembly 22 provided by some embodiments of the present application.
  • the electrode assembly 22 in some embodiments of the present application includes a first pole piece 222 , a diaphragm 223 and a second pole piece 224 , wherein the first pole piece 222 and the diaphragm 223 are respectively continuous integral structures.
  • the first pole piece 222 may also be a plurality of pole pieces with a split structure, and continuous diaphragms 223 are provided on both sides of the multiple pole pieces along the thickness direction of the pole pieces.
  • the diaphragms 223 on both sides are respectively arranged on both sides of the first pole piece 222 along the thickness direction of the pole piece.
  • the first pole piece 222 and the diaphragms 223 on both sides are folded repeatedly, so that the first pole piece 222 and the diaphragms on both sides 223 is roughly Z-shaped and reciprocally bent.
  • a second pole piece 224 is arranged between the first pole pieces 222 on adjacent sides of the laminated structure.
  • the first pole piece 222 and the second pole piece 224 are separated by a diaphragm 223. open to form the electrode assembly 22 with a laminated structure.
  • the polarity of the first pole piece 222 and the second pole piece 224 are opposite, and when one is a cathode piece, the other is an anode piece.
  • the diaphragm 223 is a microporous membrane for separating the first pole piece 222 and the second pole piece 224 , and is a polymer functional material with nanoscale pores. It is used to prevent the two pole pieces from short circuiting while allowing electrolyte ions to pass through.
  • the separator 223 can be a polyolefin microporous membrane of polyolefin material, including polyethylene (PE) single-layer membrane, polypropylene (PP) single-layer membrane and multilayer microporous membrane composed of polyethylene and polypropylene.
  • the diaphragm 223 In order to attach the diaphragm 223 on both sides of the first pole piece 222 along the thickness direction of the pole piece, the diaphragm 223 is usually coated with glue as a whole, and the diaphragm 223 is pasted on the first pole piece 222 by the viscosity of the glue, but the diaphragm is The overall gluing cost is very high, resulting in an overall high cost of manufacturing the electrode assembly 22 , and the production efficiency of the overall gluing of the separator 223 is low.
  • a diaphragm 223 without glue coating is used, but a glue layer is applied to multiple positions of the active material layer of the first pole piece 222, and the diaphragm 223 is bonded on these glue layers , so as to achieve the attachment of the diaphragm 223 to the first pole piece 222, but such an attachment method is to directly coat the adhesive layer on the active material layer, resulting in the failure of the capacity of this part of the active material.
  • the adhesive layer is in the active material layer
  • the thickness of the active material layer is not easy to control, which will affect the thickness of the entire electrode assembly 22, and the adhesive layer is coated on multiple positions of the active material layer, and the production efficiency is low.
  • FIG. 6 is a schematic diagram of the expansion of the first pole piece 222 and the diaphragm 223 provided by some embodiments of the present application
  • FIG. 7 is a cross-sectional view along the line A-A of FIG. 6
  • FIG. 8 is a schematic diagram of the first pole piece 222 in FIG. 6 .
  • the electrode assembly 22 of the embodiment of the present application includes a first pole piece 222 and a diaphragm 223 .
  • the first pole piece 222 is coated with an active material layer 2221 and a viscous material layer 2222 on both sides along the thickness direction W of the pole piece.
  • the active material layer 2221 and the viscous material layer 2222 on each side are arranged side by side along the height direction H of the pole piece, and the diaphragm 223 is arranged On both sides of the first pole piece 222 along the thickness direction W of the pole piece, and stacked with the first pole piece 222 , the dotted line box in FIG. 6 represents the outline of the first pole piece 222 .
  • the diaphragm 223 on each side of the first pole piece 222 is a continuous integral structure, and the diaphragm 223 is connected to the first pole piece 222 through the adhesive substance layer 2222 .
  • the first pole piece 222 includes a current collector 2224, a first tab 2223 extending from the end of the current collector 2224 along the height direction H of the pole piece, and a coating The active material layer 2221 and the viscous material layer 2222 applied on the current collector 2224. Both sides of the current collector 2224 along the thickness direction W of the pole piece are coated with an active material layer 2221 and a viscous material layer 2222 .
  • the viscous material layer 2222 is adjacent to the active material layer 2221 and arranged side by side.
  • the viscous material layer 2222 can extend along the pole piece length direction L and run through the entire length of the first pole piece 222.
  • Each viscous material layer 2222 and the active material layer 2222 The material layers 2221 are arranged parallel to each other along the length direction L of the pole piece.
  • the number of viscous substance layers 2222 is at least one, and when there are multiple viscous substance layers 2222 , the viscous substance layers 2222 and the active substance layers 2221 may be arranged alternately.
  • the current collector 2224 has two opposite surfaces along the thickness direction W of the pole piece, and the active material layer 2221 and the viscous material layer 2222 may be coated on both surfaces.
  • the material of the current collector 2224 is a metal material such as copper or copper alloy.
  • the current collector 2224 is made of metal materials such as aluminum or aluminum alloy.
  • the active material layer 2221 is coated on the two opposite surfaces of the first pole piece 222 along the thickness direction W of the pole piece, and the active material layer 2221 can generate electric energy through an electrochemical reaction during the charging and discharging process of the battery 2 .
  • the material of the active material layer 2221 may include but not limited to carbon or silicon.
  • the material of the active material layer 2221 may include but not limited to lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate.
  • the viscous substance layer 2222 is coated on the two opposite surfaces of the first pole piece 222 along the thickness direction W of the pole piece.
  • the viscous substance layer 2222 is composed of a material with a certain viscosity, which can bond the diaphragm 223 to the surface under certain conditions. on the first pole piece 222 .
  • the adhesive substance layer 2222 is a hot melt adhesive layer, which bonds the diaphragm 223 to the first pole piece 222 by thermal lamination.
  • integral and continuous diaphragms 223 are provided on both sides of the first pole piece 222 along the thickness direction W of the pole piece.
  • the diaphragms 223 are arranged in pairs, and the first pole piece 222 is disposed between the two diaphragms 223.
  • the overall size of the diaphragm 223 is larger than the overall size of the first pole piece 222, and the first pole piece 222 can be completely covered inside the diaphragms 223 on both sides, so that after the electrode assembly 22 is formed, the first pole piece 222 and the second pole piece 222 can be fully isolated.
  • the pole piece 224 realizes the insulation between the two.
  • two integral diaphragms 223 are respectively arranged on both sides of the first pole piece 222 along the thickness direction W of the pole piece, so that the first pole piece 222 is placed between the two diaphragms 223, and then the two The two diaphragms 223 are respectively bonded to the corresponding viscous material layers 2222 on both sides of the first pole piece 222, so that the diaphragm 223 is attached to the first pole piece 222, and the positions of the diaphragm 223 and the first pole piece 222 are fixed.
  • the diaphragm 223 After the diaphragm 223 is arranged on both sides of the first pole piece 222 along the thickness direction W of the pole piece, the diaphragm 223 can be folded back and forth with the first pole piece 222 multiple times, so that the first pole piece 222 and the diaphragms 223 on both sides are roughly Z.
  • the font is bent back and forth to form the electrode assembly 22 .
  • One end of the current collector 2224 along the pole piece height direction H is provided with a plurality of first tabs 2223 arranged at intervals.
  • the first tabs 2223 extend outward from the current collector 2224 and protrude from the viscous layer 2222 on this side.
  • a plurality of first tabs 2223 are overlapped to form a tab 221 with a multi-tab structure for electrical connection with the electrode terminal 211 .
  • the multiple dotted lines X in FIG. 8 do not represent entities, but only schematically indicate the bending positions where the first pole piece 222 and the diaphragm 223 are stacked in a zigzag shape, and these bending positions are bending regions with a certain width.
  • the viscous material layer 2222 is coated on both ends of the current collector 2224 along the pole piece height direction W, so that the diaphragm 223 is bonded to the first pole piece 222 through the viscous material layer 2222, so that the diaphragm 223
  • the position of the first pole piece 222 is fixed, and there is no need to apply an adhesive layer on the diaphragm 223, which reduces the cost and improves the production efficiency.
  • adhesive layers are applied to multiple positions of the active material layer 2221 of the first pole piece 222, and then the diaphragm 223 is bonded to these adhesive layers, so that the diaphragm 223 is attached to the first pole piece 222 , but such an attachment method is to apply the glue layer directly on the active material layer 2221, resulting in the failure of the capacity of this part of the active material.
  • the viscous material layer 2222 in order to prevent the viscous material layer 2222 from being coated on the active material layer 2221, is coated on the first pole piece 222 along the height direction H of the pole piece.
  • An active material layer 2221 is coated between the two side ends and the adhesive material layer 2222 on both sides.
  • Both ends of the current collector 2224 are coated with a viscous layer 2222, but the projections of the viscous layer 2222 and the active material layer 2221 in the thickness direction W of the pole piece do not overlap, that is, the viscous layer 2222 and the active material layer 2221 are directly coated on the current collector 2224.
  • Both the viscous material layer 2222 and the active material layer 2221 are directly coated on the current collector 2224 and arranged side by side.
  • the viscous material layer 2222 does not cover the active material layer 2221, so that it will not affect the capacity of the active material layer 2221. At the same time, it will not The overall thickness of the first pole piece 222 is increased.
  • the viscous material layer 2222 is arranged on both ends of the first pole piece 222 along the height direction H of the pole piece, so that the position of the end of the first pole piece 222 is bonded and fixed to the diaphragm 223, which can reduce the occurrence of folding of the diaphragm 223 Or the risk of wrinkles, to ensure the insulating effect of the diaphragm 223.
  • FIG. 9 is an A-A sectional view of other embodiments of FIG. 6
  • FIG. 10 is a schematic diagram of the first pole piece 222 in FIG. 9 .
  • one or more viscous material layers 2222 arranged at intervals are arranged between the viscous material layers 2222 at the ends on both sides, adjacent to each other.
  • An active material layer 2221 is coated between the two viscous material layers 2222 .
  • the viscous material layer 2222 is applied to both ends of the first pole piece 222.
  • at least one viscous substance layer 2222 may be disposed between the viscous substance layers 2222 at both ends.
  • At least one viscous material layer 2222 is evenly distributed between the viscous material layers 2222 at both ends (that is, the middle position of the first pole piece 222), and each viscous material layer 2222 is respectively adjacent to the active material layer 2221 and They are arranged side by side and do not overlap with the projection of the active material layer 2221 along the thickness direction W of the pole piece, that is, the viscous material layer 2222 and the active material layer 2221 do not cover each other.
  • Each viscous material layer 2222 and each active material layer 2221 are arranged parallel to each other along the length direction L of the pole piece.
  • the number of viscous substance layers 2222 is at least one, and when there are multiple viscous substance layers 2222 , the viscous substance layers 2222 and the active substance layers 2221 may be arranged alternately.
  • a viscous material layer 2222 in the middle can enhance the bonding effect between the separator 223 and the first pole piece 222 , and the production cost is relatively low and the production efficiency is high.
  • a plurality of viscous material layers 2222 are arranged in the middle position, while enhancing the bonding effect between the diaphragm 223 and the first pole piece 222, the flatness between the diaphragm 223 and the first pole piece 222 can be improved, and the middle part of the first pole piece 222 can be reduced.
  • the risk of wrinkling of the separator 223 at the corresponding position will not lead to an increase in the overall thickness of the electrode assembly 22 after lamination, and improve the quality of the electrode assembly 22 .
  • the width of the viscous substance layer 2222 along the height direction H of the pole piece is 2-20 mm. Since the sticky substance layer 2222 can extend along the length direction L of the pole piece and run through the entire length of the first pole piece 222, the bonding strength between the diaphragm 223 and the first pole piece 222 along the length direction L of the pole piece can be guaranteed. Layers 2222 are arranged at intervals along the pole piece height direction H, and an active material layer 2221 is arranged between adjacent viscous material layers 2222.
  • the active material layer 2221 on the first pole piece 222 corresponds to the corresponding
  • the separator 223 is not bonded and fixed, therefore, setting the width of each viscous material layer 2222 along the pole piece height direction H to 2-20 mm can improve the adhesion between the separator 223 and the first pole piece 222 along the pole piece height direction H strength.
  • Fig. 11 is an enlarged view of part II in Fig. 9 .
  • the thickness a1 of the viscous material layer 2222 along the thickness direction W of the pole piece is greater than or equal to the thickness a2 of the active material layer 2221, so that when the diaphragm 223 is attached to the first pole piece 222, it can ensure The diaphragm 223 is in contact with the viscous substance layer 2222 , so that the viscous substance layer 2222 can play the role of bonding the diaphragm 223 .
  • the thickness a1 of the viscous substance layer 2222 along the thickness direction W of the pole piece is 25-120 ⁇ m.
  • the overall thickness of a pole piece 222 can effectively control the thickness of the electrode assembly 22 .
  • the adhesive substance layer 2222 is a hot-melt adhesive layer, and the hot-melt adhesive layer connects the diaphragm 223 and the first pole piece 222 through thermal lamination. After the viscous substance layer 2222 is thermally compounded, the hot melt adhesive acts to generate viscosity, so that the diaphragm 223 is bonded to the viscous substance layer 2222 , thereby achieving the bonding effect of the diaphragm 223 and the first pole piece 222 .
  • the material of the viscous substance layer 2222 is polypropylene, which can withstand the electrolyte, and the separator 223 can be bonded to the first pole piece 222 under the action of thermal compounding at a temperature of 70-90°C. superior.
  • the diaphragm 223 is bonded on the first pole piece 222 without the need for a diaphragm 223
  • the adhesive layer is applied as a whole, which reduces the production cost and improves the production efficiency.
  • the ends of the first pole piece 222 along the height direction H of the pole piece are bonded to the diaphragm 223, and after the first pole piece 222 and the diaphragm 223 are stacked in a zigzag shape, the diaphragm 223 can be prevented from being folded and the second The contact between the first pole piece 222 and the second pole piece 224 reduces the risk of short circuit of the electrode assembly 22 .
  • FIG. 12 is a schematic diagram of the laminated first pole piece 222 in some embodiments of the present application
  • FIG. 13 is an enlarged view of part I in FIG. 5 .
  • the first pole piece 222 includes a plurality of bent sections 2225 and a plurality of stacked first stacked sections 2226, and each bent section 2225 connects two adjacent first lamination segments 2226.
  • the bending section 2225 includes a thinned portion 22251 or a cut-off portion 22252 (see FIG. 14 ), so as to facilitate bending of the first pole piece 222 .
  • the multiple bent sections 2225 in FIG. 12 correspond to the positions of multiple dotted lines X in FIG. 8 and FIG. 10 after unfolding.
  • the quantity of the bent section 2225 and the first lamination section 2226 can be set according to the size specification of the electrode assembly 22 , which is not specifically limited in this application.
  • the first pole piece 222 is a continuous overall structure.
  • an integral and continuous diaphragm 223 is respectively attached to both sides of the first pole piece 222 along the thickness direction W of the pole piece, and then The diaphragm 223 and the viscous material layer 2222 are thermally compounded, so that the diaphragm 223 is bonded to the first pole piece 222 .
  • the first pole piece 222 and the diaphragms 223 on both sides are bent in the area of the dotted line X, so that the first pole piece 222 forms a bent section 2225 .
  • the bent section 2225 includes a reduced thickness portion 22251, and the reduced thickness portion 22251 may have the same number as the bent section 2225.
  • the bent sections 2225 some A number of bent sections 2225 are provided with reduced thickness portions 22251 , while other bent sections 2225 may not be provided with reduced thickness portions 22251 .
  • the thinned portion 22251 may be a groove provided on the first pole piece 222 , and the groove may be formed by removing part of the active material layer on the first pole piece 222 .
  • the cross-sectional shape of the thinned portion 22251 perpendicular to the thickness direction W of the pole piece is V-shaped, but the cross-sectional shape of the thinned portion 22251 is not limited to V-shaped, and may also be U-shaped or rectangular.
  • One of the two adjacent thickness-reduced portions 22251 is located on one surface of the first pole piece 222 along the thickness direction W of the pole piece, and the other is located on the surface away from this surface, so that the first pole piece 222 can form a Z-shape Type reciprocating bending.
  • the reduced thickness portion 22251 is used to guide the first pole piece 222 to be bent in the region of the reduced thickness portion 22251 when making the electrode assembly 22, so as to facilitate the lamination operation. 222 is thinner, therefore, the first pole piece 222 is more likely to be bent at the thinned portion 22251, which is beneficial to improve the controllability and accuracy of the bending position.
  • FIG. 14 is a cross-sectional view of an electrode assembly 22 provided by other embodiments of the present application
  • FIG. 15 is a schematic diagram of a first pole piece 222 provided by other embodiments of the present application.
  • the bending portion 2225 of the first pole piece 222 includes a cutout portion 22252, and when the first pole piece 222 is unfolded, the cutout portion 22252 folds the first pole piece 222 is divided into a plurality of spaced first lamination segments 2226 .
  • a plurality of first lamination segments 2226 are attached to an integral diaphragm 223 at intervals, and the distance between the plurality of first lamination segments 2226 is the width of a cut-off portion 22252, and then a plurality of An integral diaphragm 223 is attached to the side of the first laminated section 2226 that is not attached to the diaphragm 223, so that multiple first laminated sections 2226 are placed between two layers of diaphragms 223, and the first pole piece 222 is completely placed on the diaphragms on both sides.
  • the diaphragm 223 and the viscous material layer 2222 on each first laminated section 2226 are thermally compounded, so that the diaphragm 223 is bonded to all the first laminated sections 2226, thereby realizing the bonding between the first pole piece 222 and the diaphragm 223 Fixed connection.
  • the diaphragm 223 and the plurality of first lamination segments 2226 are reciprocally folded at the positions of the plurality of cutting parts 22252 , so that the diaphragm 223 and the plurality of first lamination segments 2226 are stacked together.
  • the cutting part 22252 is used to guide the diaphragm 223 and the plurality of first lamination segments 2226 to be folded at the position of the cutting part 22252 when the electrode assembly 22 is manufactured, so as to facilitate the lamination operation, and the first pole piece 222 is divided by the cutting part 22252
  • the first lamination section 2226 arranged at a plurality of intervals can precisely control the dimensional accuracy of the first lamination section 2226, thereby improving the controllability and accuracy of the folding position.
  • the first pole piece 222 is an anode piece.
  • the current collector material of the anode sheet is metal material such as copper or copper alloy, and the current collector of the anode sheet is coated with an anode active material layer, and the anode active material can be carbon or silicon and other materials. Due to the characteristics of the material of the anode active material, during the working process of the electrode assembly 22 , it is easy to cause powder falling. Using the anode piece as the first pole piece 222 to be bonded to the diaphragm 223 can reduce the risk of the casing 23 being corroded due to powder falling of the anode active material material.
  • the electrode assembly 22 further includes a second pole piece 224, which is opposite in polarity to the first pole piece 222.
  • the first pole piece 222 is an anode piece
  • the sheet 224 is a cathode sheet
  • the second pole sheet 224 includes a plurality of second lamination segments 2241 , and in the stacked state of the electrode assembly 22 , each second lamination segment 2241 is disposed between two adjacent first lamination segments 2226 .
  • FIG. 16 is a schematic diagram of the connection structure of the first pole piece 222 , the second pole piece 224 and the diaphragm 223 in the unfolded state of the electrode assembly 22 of the embodiment shown in FIG. 5 .
  • diaphragms 223 are respectively arranged on both sides of the first pole piece 222 along the thickness direction W of the pole piece, so that the diaphragms 223 arranged in pairs share the same
  • the first pole piece 222 is clamped, and then the diaphragm 223 on both sides is thermally compounded with the viscous material layer 2222 of the first pole piece 222 , so that the diaphragm 223 is bonded to the first pole piece 222 .
  • the second lamination segment 2241 of the second pole piece 224 is attached to the diaphragm 223 .
  • the second lamination segment 2241 and the membrane 223 may be connected by heat pressing, electrophoresis or adhesive.
  • the two adjacent second lamination segments 2241 one of them is connected to one of the diaphragms 223 arranged in pairs, and the other is connected to the other of the diaphragms 223 arranged in pairs, so that the adjacent two The two second lamination segments 2241 are respectively disposed on opposite sides of the first pole piece 222 .
  • the first lamination section 2226 and the second lamination section 2241 are arranged corresponding to each other.
  • the first pole piece 222 , the second pole piece 224 and the diaphragm 223 are bent back and forth together to form a laminated electrode assembly 22 .
  • the formed electrode assembly 22 can better meet the use requirements and optimize the electrical performance of the electrode assembly 22 .
  • FIG. 17 is a flowchart of a method for manufacturing an electrode assembly according to an embodiment of the present application.
  • the embodiment of the present application also provides a method for manufacturing an electrode assembly, which includes the following steps:
  • Step S1 providing a first pole piece 222 .
  • the first pole piece 222 may be an anode piece.
  • Step S2 coating the active material layer 2221 and the viscous material layer 2222 on both sides of the first pole piece 222 along the thickness direction W of the pole piece, so that the active material layer 2221 and the viscous material layer 2222 are arranged adjacent to each other.
  • Step S3 providing a diaphragm 223 .
  • Diaphragm 223 may be a continuous unitary structure.
  • step S4 the diaphragm 223 is arranged on both sides of the first pole piece 222 along the thickness direction W of the pole piece, and is stacked with the first pole piece 222 .
  • Step S5 connecting the diaphragm 222 to the first pole piece 222 through the adhesive substance layer 2222 .
  • the adhesive substance layer 2222 connects the diaphragm 223 to the first pole piece 222 by thermal lamination.
  • the step S1 of providing the first pole piece includes: forming a plurality of thinning portions 22251 on the first pole piece 222 by scoring or laser cleaning. Carry out scoring or laser cleaning on the first pole piece 222, so that the first pole piece 222 removes part of the material, and the removed part of the material can be the active material material or the current collector material, so that the thickness reduction part 22251 has a higher thickness than the first pole piece 22251. Other parts of a pole piece 222 are thinner in thickness.
  • the manufacturing method of the electrode assembly further includes the following steps: laminating the separator 223 and the first pole piece 222 together, and bending at a plurality of thinned parts 22251 so that the first pole piece 222 has multiple bends
  • the bent section 2225 and a plurality of stacked first stacked sections 2226 , each bent section 2225 connects two adjacent first stacked sections 2226 .
  • the manufacturing method of the electrode assembly further includes providing a second pole piece 224, and disposing the second pole piece 224 between adjacent first lamination segments 2226 that are stacked.
  • the viscous substance layer 2222 is coated on both ends of the current collector 2224 along the pole piece height direction W, so that the separator 223 is bonded to the first pole piece 222 through the viscous substance layer 2222, thereby The positions of the diaphragm 223 and the first pole piece 222 are fixed without coating the adhesive layer on the diaphragm 223, which reduces the cost and improves the production efficiency.

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Abstract

本申请提供一种电极组件及其制作方法、电池单体、电池和用电装置，该电极组件包括：第一极片，第一极片沿极片厚度方向两侧涂敷有活性物质层和粘性物质层，每侧的活性物质层与粘性物质层沿极片高度方向并列设置；和隔膜，其设置于第一极片沿极片厚度方向两侧，并与第一极片层叠设置；在电极组件展开的状态下，第一极片每侧的隔膜为连续的整体结构，隔膜通过粘性物质层连接于第一极片。通过在第一极片涂敷粘性物质层，使隔膜通过粘性物质层粘结在第一极片上，从而将隔膜与第一极片的位置固定，而无需在隔膜上涂敷胶层，降低成本，并提高生产效率。

Description

电极组件及其制作方法、电池单体、电池和用电装置 技术领域
本申请涉及储能器件技术领域，尤其涉及一种电极组件及其制作方法、电池单体、电池和用电装置。
背景技术
节能减排是汽车产业可持续发展的关键。在这种情况下，电动车辆由于其节能环保的优势成为汽车产业可持续发展的重要组成部分。而对于电动车辆而言，电池技术又是关乎其发展的一项重要因素。因此，在电池生产过程中，降低成本，提高生产效率，具有重要意义。
发明内容
为了解决上述问题，本申请提供一种电极组件及其制作方法、电池单体、电池和用电装置，能够降低成本，提高生产效率。
本申请实施例第一方面提供一种电极组件，包括：第一极片，第一极片沿极片厚度方向两侧涂敷有活性物质层和粘性物质层，每侧的活性物质层与粘性物质层沿极片高度方向并列设置；和隔膜，其设置于第一极片沿极片厚度方向两侧，并与第一极片层叠设置；在电极组件展开的状态下，第一极片每侧的隔膜为连续的整体结构，隔膜通过粘性物质层连接于第一极片。
在上述技术方案中，通过在第一极片涂敷粘性物质层，使隔膜通过粘性物质层粘结在第一极片上，从而将隔膜与第一极片的位置固定，而无需在隔膜上涂敷胶层，降低成本，并提高生产效率。
在一些实施例中，沿极片高度方向，粘性物质层涂敷于第一极片的两侧端部，两侧粘性物质层之间涂敷有活性物质层。
在上述技术方案中，粘性物质层设置在第一极片沿极片高度方向的两侧端部，使第一极片的端部位置与隔膜粘结固定，能够减小隔膜发生翻折或褶皱的危险，保证隔膜的绝缘作用。
在一些实施例中，沿极片高度方向，两侧粘性物质层之间还设有一个或多个间 隔设置的粘性物质层，相邻两个粘性物质层之间涂覆有活性物质层。
在上述技术方案中，两侧粘性物质层之间设置一个粘性物质层，可以将增强隔膜与第一极片的粘结效果，并且生产成本相对较低，生产效率高。两侧粘性物质层之间设置多个粘性物质层，，在增强隔膜与第一极片的粘结效果的同时，能够提高隔膜与第一极片的平整性，减小第一极片中部位置对应的隔膜产生褶皱的风险，不会导致叠片后电极组件的整体厚度的增加，提高电极组件的质量。
在一些实施例中，粘性物质层沿极片高度方向的宽度为2～20mm，可以提高隔膜与第一极片沿极片高度方向的粘结强度。
在一些实施例中，粘性物质层沿极片厚度方向的厚度大于等于活性物质层的厚度，使隔膜贴附于第一极片时，能够确保隔膜与粘性物质层相接触，从而使粘性物质层能够发挥粘结隔膜的作用。
在一些实施例中，粘性物质层沿极片厚度方向的厚度为25～120μm。
在上述技术方案中，通过控制粘性物质层的厚度，不但能确保隔膜与粘性物质层粘结，还能够保证第一极片的整体厚度，从而有效控制电极组件的厚度。
在一些实施例中，粘性物质层为热熔胶层，热熔胶层通过热复合将隔膜与第一极片连接。
在上述技术方案中，粘性物质层经过热复合后，热熔胶发挥作用产生粘性，使隔膜粘结在粘性物质层，从而达到隔膜和第一极片粘结的效果。
在一些实施例中，粘性物质层的材料为聚丙烯。聚丙烯能够耐受电解液，在温度为70～90℃的热复合作用下，即可将隔膜粘结在第一极片上。
在一些实施例中，第一极片包括多个弯折段和多个层叠设置的第一层叠段，每个弯折段连接两个相邻的第一层叠段；沿极片的厚度方向，弯折段包括厚度减薄部或者切断部，以方便第一极片弯折。
在上述技术方案中，厚度减薄部和切断部用于在制作电极组件时，引导第一极片在厚度减薄部的区域发生弯折，以便于进行层叠操作，从而有利于提高弯折位置的可控性和准确性。
在一些实施例中，第一极片为阳极片。将阳极片作为第一极片与隔膜粘结连接，可以减小阳极活性物质材料掉粉而导致壳体腐蚀的风险。
在一些实施例中，电极组件还包括第二极片，与第一极片极性相反；第二极片包括多个第二层叠段，在电极组件的层叠状态，每个第二层叠段设置于相邻两个所述第一 层叠段之间。
在上述技术方案中，使成型的电极组件能够更好的满足使用要求，优化电极组件的电学性能。
本申请实施例第二方面提供一种电极组件的制作方法，包括以下步骤：提供第一极片，在第一极片沿厚度方向两侧涂敷活性物质层和粘性物质层，使活性物质层与粘性物质层相邻设置；提供隔膜，将隔膜设置于第一极片沿极片厚度方向两侧，并与第一极片层叠设置；将隔膜通过粘性物质层连接于第一极片。
在一些实施例中，粘性物质层通过热复合隔膜与第一极片连接。
在一些实施例中，在提供第一极片的步骤中包括：通过刻痕或激光清洗的方式在第一极片上形成多个厚度减薄部。
在一些实施例中，电极组件的制作方法还包括以下步骤：将隔膜与第一极片共同层叠，在多个厚度减薄部处弯折，使第一极片具有多个弯折段和多个层叠设置的第一层叠段，每个弯折段连接两个相邻的第一层叠段。
在一些实施例中，电极组件的制作方法还包括提供第二极片，将第二极片设置于层叠设置的相邻的第一层叠段之间。
本申请实施例第三方面提供一种电池单体，包括第一方面的电极组件，或包括利用第二方面的电极组件的制作方法制作的电极组件。
本申请实施例第四方面提供一种电池，包括多个第三方面的电池单体。
本申请实施例第五方面提供一种用电装置，包括如第四方面所述的电池，电池用于提供电能。
应当理解的是，以上的一般描述和后文的细节描述仅是示例性的，并不能限制本申请。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施例中所需使用的附图作简单地介绍，显而易见，以下描述的附图仅仅是本申请的具体实施例，本领域技术人员在不付出创造性劳动的前提下，可以根据以下附图获得其他实施例。
图1为本申请一些实施例提供的车辆的结构示意图；
图2为本申请一些实施例提供的电池的爆炸示意图；
图3为本申请实施例提供的一种电池模块的结构示意图；
图4为本申请一些实施例提供的电池单体的爆炸示意图；
图5为本申请一些实施例提供的电极组件的截面图；
图6为本申请一些实施例提供的第一极片和隔膜展开的示意图；
图7为图6的A-A向剖视图；
图8为图6中第一极片的示意图；
图9为图6的另一些实施例的A-A向剖视图；
图10为图9中的第一极片的示意图；
图11为图9中的Ⅱ部放大图；
图12为本申请一些实施例的第一极片层叠后的示意图；
图13为图5中的Ⅰ部放大图；
图14为本申请另一些实施例提供的电极组件的截面图；
图15为本申请另一些实施例提供的第一极片的示意图；
图16为图5所示实施例的第一极片、第二极片和隔膜连接结构示意图；
图17为本申请一个实施例的电极组件的制作方法的流程图。
附图标记：
1-车辆、2-电池、3-控制器、4-马达、5-箱体；
51-第一箱体部、52-第二箱体部、53-容纳空间；
20-电池单体；200-电池模块；
21-端盖组件、211-电极端子、212-端盖；
22-电极组件、
221-极耳、
222-第一极片、
2221-活性物质层、
2222-粘性物质层、
2223-第一极耳、
2224-集流体、
2225-弯折部、
22251-厚度减薄部、
22252-切断部、
2226-第一层叠段、
223-隔膜、
224-第二极片、
2241-第二层叠段；
23-壳体、
231-开口。
此处的附图被并入说明书中并构成本说明书的一部分，示出了符合本申请的实施例，并与说明书一起用于解释本申请的原理。
具体实施方式
为了更好地理解本申请的技术方案，下面结合附图对本申请实施例进行详细描述。
应当明确，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其它实施例，都属于本申请保护的范围。
在本申请实施例中使用的术语是仅仅出于描述特定实施例的目的，而非旨在限制本申请。在本申请实施例和所附权利要求书中所使用的单数形式的“一种”、“所述”和“该”也旨在包括多数形式，除非上下文清楚地表示其他含义。
应当理解，本文中使用的术语“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。
需要注意的是，本申请实施例所描述的“上”、“下”、“左”、“右”等方位词是以附图所示的角度来进行描述的，不应理解为对本申请实施例的限定。此外，在上下文中， 还需要理解的是，当提到一个元件连接在另一个元件“上”或者“下”时，其不仅能够直接连接在另一个元件“上”或者“下”，也可以通过中间元件间接连接在另一个元件“上”或者“下”。
本申请中出现的“多个”指的是两个以上(包括两个)。
本申请中，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，本申请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成三种：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。
本申请的实施例所提到的电池是指包括一个或多个电池单体以提供更高的电压和容量的单一的物理模块。例如，本申请中所提到的电池可以包括电池模块或电池包等。电池一般包括用于封装一个或多个电池单体的箱体。箱体可以避免液体或其他异物影响电池单体的充电或放电。
电池单体包括电极组件和电解液，电极组件由阴极极片、阳极极片和隔膜组成。电池单体主要依靠金属离子在阴极极片和阳极极片之间移动来工作。阴极极片包括阴极集流体和阴极活性物质层，阴极活性物质层涂覆于阴极集流体的表面，未涂覆阴极活性物质层的阴极集流体凸出于已涂覆阴极活性物质层的阴极集流体，未涂覆阴极活性物质层的阴极集流体作为阴极极耳。阳极活性物质层涂覆于阳极集流体的表面，未涂覆阳极活性物质层的阳极集流体凸出于已涂覆阳极活性物质层的阳极集流体，未涂覆阳极活性物质层的阳极集流体作为阳极极耳。为了保证通过大电流而不发生熔断，阴极极耳的数量为多个且层叠在一起，阳极极耳的数量为多个且层叠在一起。
电极组件可以是卷绕式结构，也可以是叠片式结构。卷绕式的电极组件是将阴极极片、阳极极片及介于阴极极片和阳极极片之间的隔膜共同进行卷绕形成的电极组件。而叠片式的电极组件，包括多个单片的阴极极片及多个单片的阳极极片以及隔膜交替堆叠层叠的结构，也可以是将一个连续的整体的极片(阳极极片或阴极极片)在沿极片厚度方向两侧贴附隔膜后再与阴极极片进行Z字型层叠，从而形成叠片式电极组件。这种隔膜完全包覆阳极极片的结构，极片厚度方向两侧的隔膜完全贴附与极片上，极片不会移位，极片不会与极片接触，可有效防止短路，可保证电池的安全，保证电池容量的充分发挥。
发明人发现，对于叠片式的电极组件，在对极片沿极片厚度方向两侧贴附隔膜 时，为了在极片沿极片厚度方向两侧贴附隔膜，通常采用整片涂胶的隔膜，利用隔膜的胶层的粘性贴附在极片上，但对隔膜进行整体涂胶的成本非常高，导致制作电极组件的成本整体变高，并且对隔膜整体涂胶的生产效率较低。
鉴于此，本申请实施例提供一种技术方案，隔膜无需涂胶，在极片的活性物质层沿极片高度方向两侧的集流体上涂敷胶层，将隔膜与集流体上的胶层粘结，实现隔膜贴附于极片，降低成本，提高生产效率。以下对本申请实施例进行详细描述。
本申请实施例描述的技术方案适用于电池以及用电装置。
用电装置可以是车辆、手机、便携式设备、笔记本电脑、轮船、航天器、电动玩具和电动工具等等。车辆可以是燃油汽车、燃气汽车或新能源汽车，新能源汽车可以是纯电动汽车、混合动力汽车或增程式汽车等；航天器包括飞机、火箭、航天飞机和宇宙飞船等等；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等等。本申请实施例对上述用电装置不做特殊限制。
以下实施例为了方便说明，以使用电池的装置为车辆为例进行说明。
图1为本申请一些实施例提供的车辆1的结构示意图。
如图1所示，车辆1的内部设置有电池2，电池2是指包括一个或多个电池单体以提供更高的电压和容量的单一的物理模块，例如，本申请中所提到的电池2可以包括电池模块或电池包等。电池2可以设置在车辆1的底部或头部或尾部。电池2可以用于车辆1的供电，例如，电池2可以作为车辆1的操作电源。车辆1还可以包括控制器3和马达4，控制器3用来控制电池2为马达4供电，例如，用于车辆1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2不仅仅可以作为车辆1的操作电源，还可以作为车辆1的驱动电源，代替或部分地代替燃油或天然气为车辆1提供驱动动力。
图2为本申请一些实施例提供的电池2的爆炸示意图。
如图2所示，电池2包括箱体5和电池单体20，电池单体20容纳于箱体5内。
箱体5用于容纳电池单体20，箱体5可以是多种结构。在一些实施例中，箱体5可以包括第一箱体部51和第二箱体部52，第一箱体部51与第二箱体部52相互盖合，第一箱体部51和第二箱体部52共同限定出用于容纳电池单体21的容纳空间53。第二 箱体部52可以是一端开口的空心结构，第一箱体部51可以为板状结构，第一箱体部51盖合于第二箱体部52的开口侧，以形成具有容纳空间53的箱体5；第一箱体部51和第二箱体部52也均可以是一侧开口的空心结构，第一箱体部51的开口侧盖合于第二箱体部52的开口侧，以形成具有容纳空间53的箱体5。当然，第一箱体部51和第二箱体部52可以是多种形状，比如，圆柱体、长方体等。
为提高第一箱体部51与第二箱体部52连接后的密封性，第一箱体部51与第二箱体部52之间也可以设置密封件，比如，密封胶、密封圈等。
当第一箱体部51盖合于第二箱体部52的顶部，第一箱体部51亦可称之为上箱盖，第二箱体部52亦可称之为下箱体。
在电池2中，电池单体20为多个。多个电池单体20之间可串联或并联或混联，混联是指多个电池单体20中既有串联又有并联。多个电池单体20之间可直接串联或并联或混联在一起，再将多个电池单体20构成的整体容纳于箱体5内；当然，也可以是多个电池单体20先串联或并联或混联组成电池组，多个电池组再串联或并联或混联形成一个整体，并容纳于箱体5内。
图3为本申请实施例提供的一种电池模块200的结构示意图。
如图3所示，由于每个电池2中包括的电池单体20的数量可能较多，为了便于安装，可以将电池单体20分组设置，每组电池单体20组成电池模块200。电池2可以包括多个电池模块200，这些电池模块200可通过串联、并联或混联的方式进行连接。
图4为本申请一些实施例提供的电池单体20的爆炸示意图。
请参见图4，电池单体20是指用以组成电池2的最小组成单元，在本申请的一些实施例中，电池单体20可以包括锂离子二次电池单体、锂离子一次电池单体、锂硫电池单体、钠锂离子电池单体、钠离子电池单体或镁离子电池单体等，本申请实施例对此不限定。电池单体20可呈扁平体、长方体或其它形状等，本申请实施例对此也不限定，为便于说明，在下述实施例中均以长方体形状的电池单体20为示例。
请继续参见图4，电池单体20包括端盖组件21、电极组件22和壳体23。壳体23用于将电极组件22容纳于壳体23内。壳体23可以是多种形状和多种尺寸的，具体地，壳体23的形状可以根据一个或多个电极组件22的具体形状和尺寸大小来确定。在一些实施例中，壳体23为中空的长方体。在另一些实施例中，壳体23可以是圆柱形或其他形状。壳体23的一端为开口231，端盖组件21覆盖该开口231并且与壳体23连接，形成放置电极组件22的封闭的腔体。腔体内可以填充有电解液。在一些实施例中， 端盖组件21包括端盖212，端盖212上设置有电极端子211，电极组件22上设置有极耳221，电极端子211可以用于与极耳221电连接，以用于输出电池单体20的电能。每个电极端子211可以对应设置有集流构件，可以使该集流构件位于端盖212和极耳221之间，以使电极端子211和极耳221可以通过集流构件实现电连接。端盖组件21还可以设置有其他功能性部件，例如，用于在电池单体20的内部压力或温度达到阈值时泄放内部压力的泄压机构。壳体23和端盖212的材质可以是多种，比如，铜、铁、铝、不锈钢、铝合金等。
图5为本申请一些实施例提供的电极组件22的截面图。
如图5所示，本申请一些实施例的电极组件22包括第一极片222、隔膜223和第二极片224，其中，第一极片222和隔膜223分别为连续的整体结构。在另一些实施例中，第一极片222也可以是多个分体结构的极片，在多个极片沿极片厚度方向的两侧设置连续的隔膜223。
两侧隔膜223分别设置在第一极片222沿极片厚度方向的两侧，第一极片222与两侧的隔膜223呈多次往复折叠状态，使第一极片222与两侧的隔膜223大致呈Z字型往复弯折，在层叠结构的相邻两侧第一极片222之间设置有第二极片224，第一极片222与第二极片224之间通过隔膜223隔开，形成层叠结构的电极组件22。第一极片222和第二极片224的极性相反，其中一者为阴极片时，另一者为阳极片。隔膜223是用于隔开第一极片222和第二极片224的微孔膜，是具有纳米级微孔的高分子功能材料。其用于防止两个极片接触而发生短路，同时又可以使电解质离子通过。隔膜223可以为聚烯烃材料的聚烯烃微孔膜，包括聚乙烯(PE)单层膜、聚丙烯(PP)单层膜以及由聚乙烯和聚丙烯复合而成的多层微孔膜。
为了在第一极片222沿极片厚度方向两侧贴附隔膜223，通常采用对隔膜223整体涂胶的方式，将隔膜223通过胶的粘性粘贴在第一极片222上，但对隔膜进行整体涂胶的成本非常高，导致制作电极组件22的成本整体变高，并且对隔膜223整体涂胶的生产效率较低。
在一些技术中，为了降低成本，采用不涂胶的隔膜223，而是在第一极片222的活性物质层的多个位置上涂敷胶层，再将隔膜223粘结在这些胶层上，从而实现隔膜223贴附于第一极片222，但这样的贴附方式是将胶层直接涂敷在活性物质层上，导致这一部分活性物质的容量无法发挥，同时，胶层在活性物质上的厚度不易控制，会影响整个电极组件22的厚度，并且在活性物质层的多个位置上涂敷胶层，生产效率较低。
图6为本申请一些实施例提供的第一极片222和隔膜223展开的示意图，图7为图6的A-A向剖视图，图8为图6中第一极片222的示意图。
如图6至图8所示，本申请实施例的电极组件22，包括第一极片222和隔膜223。第一极片222沿极片厚度方向W两侧涂敷有活性物质层2221和粘性物质层2222，每侧的活性物质层2221与粘性物质层2222沿极片高度方向H并列设置，隔膜223设置于第一极片222沿极片厚度方向W两侧，并与第一极片222层叠设置，图6中的虚线框表示第一极片222的轮廓。在电极组件22展开的状态下，第一极片222每侧的隔膜223为连续的整体结构，隔膜223通过粘性物质层2222连接于第一极片222。
请继续参照图7和图8，在一些实施例中，第一极片222包括集流体2224、从集流体2224沿极片高度方向H一侧端部延伸出的第一极耳2223、以及涂敷在集流体2224上的活性物质层2221和粘性物质层2222。集流体2224沿极片厚度方向W两侧均涂敷有活性物质层2221和粘性物质层2222。沿极片高度方向H，粘性物质层2222与活性物质层2221邻接且并列设置，粘性物质层2222可以沿极片长度方向L延伸并贯穿第一极片222全长，各粘性物质层2222及活性物质层2221沿极片长度方向L互相平行设置。粘性物质层2222的数量为至少一个，当粘性物质层2222为多个时，粘性物质层2222可以与活性物质层2221交替设置。
集流体2224具有沿极片厚度方向W相对的两个表面，两个表面上均可以涂敷有活性物质层2221和粘性物质层2222。在一个具体示例中，第一极片222为阳极片时，集流体2224的材料为铜或铜合金等金属材料。第一极片222为阴极片时，集流体2224的材料为铝或铝合金等金属材料。
活性物质层2221涂敷在第一极片222沿极片厚度方向W相对的两个表面上，活性物质层2221能够在电池2进行充放电的过程中发生电化学反应产生电能。当第一极片222为阳极片时，活性物质层2221的材料可以包括但不限于碳或硅等。当第一极片222为阴极片时，活性物质层2221的材料可以包括但不限于钴酸锂、磷酸铁锂、三元锂或锰酸锂等。
粘性物质层2222涂敷在第一极片222沿极片厚度方向W相对的两个表面上，粘性物质层2222为具有一定黏粘性的材料组成，其在一定条件下可以将隔膜223粘结在第一极片222上。在一些实施例中，粘性物质层2222为热熔胶层，其通过热复合将隔膜223粘结在第一极片222上。
在一些实施例中，在第一极片222沿极片厚度方向W的两侧分别设置整体连续 的隔膜223，隔膜223成对设置，第一极片222设置于两个隔膜223之间。隔膜223的整体尺寸大于第一极片222的整体尺寸，能够将第一极片222完全包覆在两侧隔膜223内部，从而在形成电极组件22后，充分隔离第一极片222和第二极片224，实现二者之间的绝缘。
在制作电池组件22时，将两个整体的隔膜223分别设置在第一极片222沿极片厚度方向W的两侧，使第一极片222置于两个隔膜223之间，再将两个隔膜223分别粘结在第一极片222两侧对应的粘性物质层2222上，实现隔膜223贴附于第一极片222，并使隔膜223和第一极片222的位置固定。
在第一极片222沿极片厚度方向W两侧设置好隔膜223后，隔膜223可以与第一极片222共同多次往复折叠，使第一极片222与两侧的隔膜223大致呈Z字型往复弯折，形成电极组件22。集流体2224沿极片高度方向H的一侧端部设有多个间隔设置的第一极耳2223，第一极耳2223从集流体2224向外侧延伸并突出于该侧的粘性物质层2222。将第一极片222进行Z字型层叠后，多个第一极耳2223重叠，形成多极耳结构的极耳221，以和电极端子211电连接。
图8中的多个虚线X并不表示实体，只是示意性地标示第一极片222和隔膜223呈Z字型层叠的弯折位置，并且这些弯折位置为具有一定宽度的弯折区域。
在上述实施例中，通过在集流体2224沿极片高度方向W两侧端部涂敷粘性物质层2222，使隔膜223通过粘性物质层2222粘结在第一极片222上，从而将隔膜223与第一极片222的位置固定，而无需在隔膜223上涂敷胶层，降低了成本，并提高了生产效率。
在一些技术中，在第一极片222的活性物质层2221的多个位置上涂敷胶层，再将隔膜223粘结在这些胶层上，从而实现隔膜223贴附于第一极片222，但这样的贴附方式是将胶层直接涂敷在活性物质层2221上，导致这一部分活性物质的容量无法发挥。
请继续参照图7和图8，在一些实施例中，为了避免粘性物质层2222涂敷在活性物质层2221上，沿极片高度方向H，粘性物质层2222涂敷于第一极片222的两侧端部，两侧粘性物质层2222之间涂敷有活性物质层2221。
集流体2224的两侧端部均涂敷有粘性物质层2222，但粘性物质层2222和活性物质层2221在极片厚度方向W上的投影不存在重合，即粘性物质层2222和活性物质层2221均直接涂敷在集流体2224上。
粘性物质层2222与活性物质层2221均直接涂敷在集流体2224上且并列设置， 粘性物质层2222没有覆盖活性物质层2221，从而不会影响活性物质层2221的容量发挥，同时，也不会增加第一极片222的整体厚度。并且，粘性物质层2222设置在第一极片222沿极片高度方向H的两侧端部，使第一极片222的端部位置与隔膜223粘结固定，能够减小隔膜223发生翻折或褶皱的危险，保证隔膜223的绝缘作用。
图9为图6的另一些实施例的A-A向剖视图，图10为图9中的第一极片222的示意图。
如图9和图10所示，在一些实施例中，沿极片高度方向H，两侧端部的粘性物质层2222之间还设有一个或多个间隔设置的粘性物质层2222，相邻两个粘性物质层2222之间涂覆有活性物质层2221。
沿极片高度方向H，粘性物质层2222涂敷于第一极片222的两侧端部，对于高度较大的第一极片222，为了增强隔膜223与第一极片222的粘结效果，可以在两侧端部的粘性物质层2222之间设置至少一个粘性物质层2222。可以理解的是，至少一个粘性物质层2222均匀分布在两侧端部的粘性物质层2222之间(即第一极片222的中部位置)，各粘性物质层2222分别与活性物质层2221邻接且并列设置，并与活性物质层2221沿极片厚度方向W的投影不重合，即粘性物质层2222与活性物质层2221互不覆盖。各粘性物质层2222及各活性物质层2221之间沿极片长度方向L互相平行设置。粘性物质层2222的数量为至少一个，当粘性物质层2222为多个时，粘性物质层2222可以与活性物质层2221交替设置。
在中部位置设置一个粘性物质层2222，可以增强隔膜223与第一极片222的粘结效果，并且生产成本相对较低，生产效率高。在中部位置设置多个粘性物质层2222，在增强隔膜223与第一极片222的粘结效果的同时，能够提高隔膜223与第一极片222的平整性，减小第一极片222中部位置对应的隔膜223产生褶皱的风险，不会导致叠片后电极组件22的整体厚度的增加，提高电极组件22的质量。
在一些实施例中，粘性物质层2222沿极片高度方向H的宽度为2～20mm。由于粘性物质层2222可以沿极片长度方向L延伸并贯穿第一极片222全长，因此，可以保证隔膜223与第一极片222沿极片长度方向L的粘结强度，但各粘性物质层2222沿极片高度方向H是间隔设置的，相邻量粘性物质层2222之间设置有活性物质层2221，由于隔膜223不具有粘性，在第一极片222的活性物质层2221与所对应的隔膜223并未粘结固定，因此，将各粘性物质层2222沿极片高度方向H的宽度设置为2～20mm，可以提高隔膜223与第一极片222沿极片高度方向H的粘结强度。
图11为图9中的Ⅱ部放大图。
如图11所示，在一些实施例中，粘性物质层2222沿极片厚度方向W的厚度a1大于等于活性物质层2221的厚度a2，使隔膜223贴附于第一极片222时，能够确保隔膜223与粘性物质层2222相接触，从而使粘性物质层2222能够发挥粘结隔膜223的作用。
在一些实施例中，粘性物质层2222沿极片厚度方向W的厚度a1为25～120μm，通过控制粘性物质层2222的厚度，不但能确保隔膜223与粘性物质层2222粘结，还能够保证第一极片222的整体厚度，从而有效控制电极组件22的厚度。
在一些实施例中，粘性物质层2222为热熔胶层，热熔胶层通过热复合将隔膜223与第一极片222连接。粘性物质层2222经过热复合后，热熔胶发挥作用产生粘性，使隔膜223粘结在粘性物质层2222，从而达到隔膜223和第一极片222粘结的效果。
在一些实施例中，粘性物质层2222的材料为聚丙烯，聚丙烯能够耐受电解液，在温度为70～90℃的热复合作用下，即可将隔膜223粘结在第一极片222上。
由于在第一极片222的集流体2224沿极片高度方向H两侧端部和中部位置涂敷粘性物质层2222，使隔膜223粘结在第一极片222上，而无需在隔膜223上整体涂敷胶层，降低了生产成本，提高了生产效率。将第一极片222的沿极片高度方向H两侧端部与隔膜223粘结连接，将第一极片222和隔膜223共同进行Z字型层叠后，能够避免隔膜223翻折而使第一极片222和第二极片224接触，降低了电极组件22发生短路的风险。
图12为本申请一些实施例的第一极片222层叠后的示意图，图13为图5中的Ⅰ部放大图。
如图5、图12和图13所示，在一些实施例中，第一极片222包括多个弯折段2225和多个层叠设置的第一层叠段2226，每个弯折段2225连接两个相邻的第一层叠段2226。沿极片的厚度方向W，弯折段2225包括厚度减薄部22251或者切断部22252(见图14)，以方便第一极片222弯折。
图12中的多个弯折段2225展开后对应图8和图10中多个虚线X的位置区域，图8、图10和图12只是示例性地说明第一极片222的结构，具体的弯折段2225和第一层叠段2226的数量可以根据电极组件22的尺寸规格进行设置，本申请对此不作具体限定。
图5和图12中第一极片222为一个连续的整体结构，在制作电极组件时，先在 第一极片222沿极片厚度方向W两侧分别贴附一个整体连续的隔膜223，再将隔膜223与粘性物质层2222进行热复合，使隔膜223与第一极片222粘结连接。在对第一极片222进行Z字型层叠时，将第一极片222与两侧的隔膜223在虚线X的位置区域进行弯折，从而使第一极片222形成弯折段2225。
图13所示的实施例中，弯折段2225包括厚度减薄部22251，厚度减薄部22251可以与弯折段2225的数量相同，当然，可以理解地，所有弯折段2225中，有部分数量的弯折段2225设置厚度减薄部22251，而其他的弯折段2225可以不设置厚度减薄部22251。
厚度减薄部22251可以是设置在第一极片222上的凹槽，该凹槽可以是去除第一极片222上的部分活性物质层形成。在一个示例中，厚度减薄部22251在垂直于极片厚度方向W的截面形状为V形，但厚度减薄部22251的截面形状并不仅限于V形，也可以是U形或矩形等。
相邻两个厚度减薄部22251的其中一个位于第一极片222沿极片厚度方向W的一个表面，另一个位于与该表面相背离的表面，从而使第一极片222能够呈Z字型往复弯折。
厚度减薄部22251用于在制作电极组件22时，引导第一极片222在厚度减薄部22251的区域发生弯折，以便于进行层叠操作，由于厚度减薄部22251具有比第一极片222更薄的厚度，因此，第一极片222更易在厚度减薄部22251处产生弯折，从而有利于提高弯折位置的可控性和准确性。
图14为本申请另一些实施例提供的电极组件22的截面图；图15为本申请另一些实施例提供的第一极片222的示意图。
如图14和图15所示，在另一些实施例中，第一极片222的弯折部2225包括切断部22252，在第一极片222展开的状态下，切断部22252将第一极片222分割为多个间隔的第一层叠段2226。在制作电极组件22时，将多个第一层叠段2226间隔贴附至一个整体的隔膜223上，多个第一层叠段2226之间间隔的距离为一个切断部22252的宽度，再在多个第一层叠段2226未贴附隔膜223一侧贴附一个整体的隔膜223，以将多个第一层叠段2226置于两层隔膜223之间，将第一极片222完全置于两侧隔膜223之间后，将隔膜223与每个第一层叠段2226上的粘性物质层2222进行热复合，使隔膜223与全部第一层叠段2226粘结，从而实现第一极片222与隔膜223的固定连接。之后再将隔膜223与多个第一层叠段2226在多个切断部22252的位置进行往复折叠，以使隔 膜223与多个第一层叠段2226共同层叠设置。
切断部22252用于在制作电极组件22时，引导隔膜223与多个第一层叠段2226在切断部22252的位置进行折叠，以便于进行层叠操作，并且由于切断部22252将第一极片222分割为多个间隔设置的第一层叠段2226，能够精确地控制第一层叠段2226的尺寸精度，从而有利于提高折叠位置的可控性和准确性。
在一些实施例中，所述第一极片222为阳极片。阳极片的集流体材料为铜或铜合金等金属材料，阳极片的集流体上涂覆有阳极活性物质层，阳极活性物质可以为碳或硅等材料。由于阳极活性物质材料特性，在电极组件22工作过程中，容易产生掉粉的情况发生。将阳极片作为第一极片222与隔膜223粘结连接，可以减小阳极活性物质材料掉粉而导致壳体23腐蚀的风险。
请继续参考图5和图14，在一些实施例中，电极组件22还包括第二极片224，与第一极片222极性相反，当第一极片222为阳极片时，第二极片224为阴极片；第二极片224包括多个第二层叠段2241，在电极组件22的层叠状态，每个第二层叠段2241设置于相邻两个第一层叠段2226之间。
图16为图5所示实施例的电极组件22在展开的状态下的第一极片222、第二极片224和隔膜223连接结构示意图。
如图16所示，在制作电极组件22时，以第一极片222为基础，在第一极片222沿极片厚度方向W方向两侧分别设置隔膜223，使得成对设置的隔膜223共同夹持第一极片222，再将两侧的隔膜223与第一极片222的粘性物质层2222进行热复合，使隔膜223与第一极片222粘结连接。在一个示例中，在第一极片222上设置好隔膜223后，将第二极片224的第二层叠段2241附接于隔膜223上。例如，第二层叠段2241和隔膜223可以通过热压、电泳或粘接方式连接。相邻的两个第二层叠段2241中，其中一个连接于成对设置的隔膜223中的其中一者，另一个连接于成对设置的隔膜223中的另一者，以使相邻的两个第二层叠段2241分别设置于第一极片222的相对两侧。沿极片厚度方向W，第一层叠段2226和第二层叠段2241彼此位置相对应设置。将第一极片222、第二极片224和隔膜223共同进行往复弯折，形成层叠的电极组件22。通过上述设置，使得成型的电极组件22能够更好的满足使用要求，优化电极组件22的电学性能。
图17为本申请一个实施例的电极组件的制作方法的流程图。
如图17所示，本申请实施例还提供一种电极组件的制作方法，该方法包括以下步骤：
步骤S1，提供第一极片222。在一些实施例中，第一极片222可以是阳极片。
步骤S2，在第一极片222沿极片厚度方向W两侧涂敷活性物质层2221和粘性物质层2222，使活性物质层2221与粘性物质层2222相邻设置。
步骤S3，提供隔膜223。隔膜223可以是连续的整体结构。
步骤S4，将隔膜223设置于第一极片222沿极片厚度方向W两侧，并与第一极片222层叠设置。
步骤S5，将隔膜222通过粘性物质层2222连接于第一极片222。
在一些实施例中，粘性物质层2222通过热复合使隔膜223与第一极片222连接。
在一些实施例中，在提供第一极片的步骤S1中包括：通过刻痕或激光清洗的方式在第一极片222上形成多个厚度减薄部22251。对第一极片222进行刻痕或激光清洗，使第一极片222去除部分材料，去除的部分材料可以是活性物质材料，也可以是集流体材料，从而使厚度减薄部22251具有比第一极片222其他部分更薄的厚度。
在一些实施例中，电极组件的制作方法还包括以下步骤：将隔膜223与第一极片222共同层叠，在多个厚度减薄部22251处弯折，使第一极片222具有多个弯折段2225和多个层叠设置的第一层叠段2226，每个弯折段2225连接两个相邻的第一层叠段2226。
在一些实施例中，电极组件的制作方法还包括提供第二极片224，将第二极片224设置于层叠设置的相邻的第一层叠段2226之间。
本申请的电极组件的制作方法，通过在集流体2224沿极片高度方向W两侧端部涂敷粘性物质层2222，使隔膜223通过粘性物质层2222粘结在第一极片222上，从而将隔膜223与第一极片222的位置固定，而无需在隔膜223上涂敷胶层，降低了成本，并提高了生产效率。
以上所述仅为本申请的优选实施例而已，并不用于限制本申请，对于本领域的技术人员来说，本申请可以有各种更改和变化。凡在本申请的精神和原则之内，所作的任何修改、等同替换、改进等，均应包含在本申请的保护范围之内。

Claims (19)

  1. 一种电极组件，其特征在于，包括：
    第一极片，所述第一极片沿极片厚度方向两侧涂敷有活性物质层和粘性物质层，每侧的所述活性物质层与所述粘性物质层沿极片高度方向并列设置；和
    隔膜，其设置于所述第一极片沿极片厚度方向两侧，并与所述第一极片层叠设置；
    在所述电极组件展开的状态下，所述第一极片每侧的所述隔膜为连续的整体结构，所述隔膜通过所述粘性物质层连接于所述第一极片。
  2. 根据权利要求1所述的电极组件，其特征在于，沿极片高度方向，所述粘性物质层涂敷于所述第一极片的两侧端部，两侧所述粘性物质层之间涂敷有所述活性物质层。
  3. 根据权利要求2所述的电极组件，其特征在于，沿极片高度方向，两侧所述粘性物质层之间还设有一个或多个间隔设置的所述粘性物质层，相邻两个所述粘性物质层之间涂覆有所述活性物质层。
  4. 根据权利要求1-3任一项所述的电极组件，其特征在于，所述粘性物质层沿极片高度方向的宽度为2～20mm。
  5. 根据权利要求1-4任一项所述的电极组件，其特征在于，所述粘性物质层沿极片厚度方向的厚度大于等于所述活性物质层的厚度。
  6. 根据权利要求1-5任一项所述的电极组件，其特征在于，所述粘性物质层沿极 片厚度方向的厚度为25～120μm。
  7. 根据权利要求1-6任一项的电极组件，其特征在于，所述粘性物质层为热熔胶层，所述热熔胶层通过热复合将所述隔膜与所述第一极片连接。
  8. 根据权利要求1-7任一项的电极组件，其特征在于，所述粘性物质层的材料为聚丙烯。
  9. 根据权利要求1-8任一项的电极组件，其特征在于，所述第一极片包括多个弯折段和多个层叠设置的第一层叠段，每个所述弯折段连接两个相邻的所述第一层叠段；沿极片的厚度方向，所述弯折段包括厚度减薄部或者切断部，以方便所述第一极片弯折。
  10. 根据权利要求1-9任一项所述的电极组件，其特征在于，所述第一极片为阳极片。
  11. 根据权利要求1-10任一项所述的电极组件，其特征在于，还包括第二极片，与所述第一极片极性相反；所述第二极片包括多个第二层叠段，在所述电极组件的层叠状态，每个所述第二层叠段设置于相邻两个所述第一层叠段之间。
  12. 一种电极组件的制作方法，其特征在于，包括以下步骤：
    提供第一极片，在所述第一极片沿厚度方向两侧涂敷活性物质层和粘性物质层，使所述活性物质层与所述粘性物质层相邻设置；
    提供隔膜，将所述隔膜设置于所述第一极片沿极片厚度方向两侧，并与所述第一 极片层叠设置；
    将所述隔膜通过所述粘性物质层连接于所述第一极片。
  13. 根据权利要求12所述的制作方法，其特征在于，所述粘性物质层通过热复合使所述隔膜与所述第一极片连接。
  14. 根据权利要求12或13所述的制作方法，其特征在于，在所述提供第一极片的步骤中包括：
    通过刻痕或激光清洗的方式在所述第一极片上形成多个厚度减薄部。
  15. 根据权利要求14所述的制作方法，其特征在于，还包括以下步骤：将所述隔膜与所述第一极片共同层叠，在所述多个厚度减薄部处弯折，使所述第一极片具有多个弯折段和多个层叠设置的第一层叠段，每个所述弯折段连接两个相邻的所述第一层叠段。
  16. 根据权利要求12-15任一项所述的制作方法，其特征在于，还包括提供第二极片，将所述第二极片设置于层叠设置的相邻的所述第一层叠段之间。
  17. 一种电池单体，其特征在于，包括如权利要求1-11任一项所述的电极组件，或包括利用权利要求12-16任一项所述的电极组件的制作方法制作的电极组件。
  18. 一种电池，其特征在于，包括至少一个如权利要求17所述的电池单体。
  19. 一种用电装置，其特征在于，包括如权利要求18所述的电池，所述电池用于提供电能。
PCT/CN2021/130772 2021-11-15 2021-11-15 电极组件及其制作方法、电池单体、电池和用电装置 WO2023082290A1 (zh)

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CN213340434U (zh) * 2020-09-22 2021-06-01 宁德时代新能源科技股份有限公司 电极组件、电池单体、电池以及用电装置
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CN111293315A (zh) * 2020-02-25 2020-06-16 东莞塔菲尔新能源科技有限公司 一种防止极耳倒插降低电芯失效的方法
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