WO2023206192A1 - 电池单体、电池、用电设备、电极组件及其制造方法 - Google Patents

电池单体、电池、用电设备、电极组件及其制造方法 Download PDF

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Publication number
WO2023206192A1
WO2023206192A1 PCT/CN2022/089733 CN2022089733W WO2023206192A1 WO 2023206192 A1 WO2023206192 A1 WO 2023206192A1 CN 2022089733 W CN2022089733 W CN 2022089733W WO 2023206192 A1 WO2023206192 A1 WO 2023206192A1
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WIPO (PCT)
Prior art keywords
negative electrode
positive electrode
tabs
tab
winding
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Ceased
Application number
PCT/CN2022/089733
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English (en)
French (fr)
Inventor
柴志生
许虎
谷慧
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Contemporary Amperex Technology Co Ltd
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Contemporary Amperex Technology Co Ltd
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Filing date
Publication date
Application filed by Contemporary Amperex Technology Co Ltd filed Critical Contemporary Amperex Technology Co Ltd
Priority to PCT/CN2022/089733 priority Critical patent/WO2023206192A1/zh
Priority to CN202280034760.7A priority patent/CN117280539A/zh
Priority to EP22939044.8A priority patent/EP4468508A4/en
Priority to CN202311785795.7A priority patent/CN117712635B/zh
Publication of WO2023206192A1 publication Critical patent/WO2023206192A1/zh
Priority to US18/774,373 priority patent/US20240372153A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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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
    • H01M50/50—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
    • 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
    • H01M10/0431—Cells with wound or folded 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
    • H01M10/058—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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • 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
    • 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
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/249—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders specially adapted for aircraft or vehicles, e.g. cars or trains
    • 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
    • H01M50/536—Electrode connections inside a battery casing characterised by the method of fixing the leads to the electrodes, e.g. by welding
    • 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
    • H01M50/572—Means for preventing undesired use or discharge
    • H01M50/584—Means for preventing undesired use or discharge for preventing incorrect connections inside or outside the batteries
    • H01M50/59—Means for preventing undesired use or discharge for preventing incorrect connections inside or outside the batteries characterised by the protection means
    • H01M50/593—Spacers; Insulating plates
    • 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
    • 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
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • 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
    • H01M50/543—Terminals
    • H01M50/547—Terminals characterised by the disposition of the terminals on the cells
    • H01M50/55—Terminals characterised by the disposition of the terminals on the cells on the same side of the cell
    • 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 disclosure relates to the field of battery technology, and in particular to a battery cell, a battery, an electrical device, an electrode assembly and a manufacturing method thereof.
  • 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 or safety issues related to the tabs during its formation process.
  • an electrode assembly comprising:
  • the main body part includes a positive electrode piece, a negative electrode piece and a separator arranged between the positive electrode piece and the negative electrode piece.
  • the positive electrode piece, the separator and the negative electrode piece are rolled along the winding direction. Winding into a coiled structure;
  • a plurality of positive electrode tabs are respectively connected to at least two positive electrode sheet winding layers in the winding structure, and are arranged at intervals along the winding direction;
  • a plurality of negative electrode tabs are respectively connected to at least two negative electrode tab winding layers in the winding structure, and are arranged at intervals along the winding direction;
  • the plurality of positive electrode tabs and the plurality of negative electrode tabs are located at the end of the same side of the main body in a direction perpendicular to the winding direction, and are respectively connected to each positive electrode sheet winding layer.
  • the length of the positive electrode tab in the winding direction increases along the winding direction
  • the length of the negative electrode tab connected to each negative electrode tab winding layer in the winding direction increases along the winding direction.
  • each positive pole tab after the pole piece is wound can be bent and smoothed according to the corresponding pole
  • the wound structure is a cylindrical wound structure wound about a winding axis.
  • the positive electrode tab and the negative electrode tab are located on the same side of the cylindrical winding structure. , can effectively reduce the internal resistance of the battery and improve the heat dissipation of the battery.
  • the circumference of the pole piece winding layer of the cylindrical winding structure gradually decreases from the outside to the inside, the length of the tab corresponding to each layer also decreases. , so that each layer of tabs will be more aligned after being smoothed toward the center of the circle, which facilitates separation of the positive and negative electrodes and facilitates subsequent tab welding.
  • the spacing between the pole tabs connected by each pole piece winding layer can enable the winding of the positive pole tab and the negative pole tab to be partitioned, reducing the inefficiency of the two pole piece groups with opposite polarity after smoothing. Risk of short circuit due to separation.
  • the angular range of the plurality of positive electrode tabs at the end of the main body part relative to the winding axis is the same as the angle range of the plurality of negative electrode tabs at the end of the main body part relative to the winding axis.
  • the angle ranges of the above winding axes do not coincide.
  • At least one positive electrode tab among the plurality of positive electrode tabs has at least one first notch on a side away from the positive electrode tab, and the at least one first notch connects the positive electrode tab to the side of the positive electrode tab.
  • the tabs are divided into a plurality of positive electrode tab segments along the winding direction; and/or at least one negative electrode tab among the plurality of negative electrode tabs has at least one first negative electrode tab on the side away from the negative electrode tab. Two notches, the at least one second notch separates the negative electrode tab into a plurality of negative electrode tab segments along the winding direction.
  • the positive electrode tab By setting a first notch on the side of the positive electrode tab to obtain multiple separated positive electrode tab segments, the positive electrode tab is less likely to wrinkle when smoothed, and the risk of tab breakage and wrinkles caused by wrinkles is reduced. Risk of short circuit caused by partial insertion between pole pieces.
  • the negative electrode tab By setting a second notch on the side of the negative electrode tab to obtain multiple separated negative electrode tab segments, the negative electrode tab is less likely to wrinkle when smoothed, and reduces the risk of tab breakage caused by wrinkles. And the wrinkled part is inserted between the pole pieces, causing the risk of short circuit.
  • the width of each positive electrode tab segment in the winding direction is the same, and the number of positive electrode tab segments in the positive electrode tabs respectively connected to each positive electrode tab winding layer is along the winding direction.
  • the direction increases; the width of each negative electrode tab segment in the winding direction is the same, and the number of negative electrode tab segments in the negative electrode tabs respectively connected to each negative electrode tab winding layer increases along the winding direction.
  • positive electrode tab segments with the same width can reduce the processing difficulty of the positive electrode tab and make the smoothed positive electrode tab group more tidy.
  • the number of positive electrode tab segments connected through each positive electrode sheet winding layer Changes to achieve corresponding changes in the length of the positive electrode tab.
  • using negative electrode tab segments with the same width can reduce the processing difficulty of the negative electrode tab and make the smoothed negative electrode tab group more tidy.
  • the negative electrode tabs connected through each negative electrode sheet winding layer The change in the number of segments realizes the corresponding change in the length of the negative electrode tab.
  • the plurality of positive electrode tabs and the plurality of negative electrode tabs satisfy at least one of the following:
  • the upstream end positions of the positive electrode tabs connected to each positive electrode sheet winding layer in the winding direction are all located on the same plane;
  • the positive electrode tabs connected to each positive electrode sheet winding layer are all located on the same plane at the most downstream end positions in the winding direction;
  • the upstream end positions of the negative electrode tabs connected to each negative electrode tab winding layer in the winding direction are all located on the same plane;
  • the most downstream end positions of the negative electrode tabs connected to each negative electrode tab winding layer in the winding direction are all located on the same plane.
  • the upstream end position and the most downstream end position of the positive electrode tabs connected to each positive electrode sheet winding layer in the winding direction are both located on the same plane; and/or each The upstream end position and the most downstream end position of the negative electrode tabs respectively connected to the negative electrode tab winding layer in the winding direction are located on the same plane.
  • an overall arcuate positive electrode tab group By aligning the upstream end position and the most downstream end position of the positive electrode tabs connected to each positive electrode sheet winding layer to the same plane in the winding direction, an overall arcuate positive electrode tab group can be formed. , this bow-shaped positive electrode tab group can keep both ends neat after being smoothed inward, thereby effectively separating it from the negative electrode tab group, and also facilitating the welding of itself to the current collecting plate. Similarly, by aligning the upstream end position and the most downstream end position of the negative electrode tabs connected to each negative electrode tab winding layer in the winding direction to the same plane, an overall arcuate negative electrode can be formed. The bow-shaped negative electrode tab group can keep both ends neat after being smoothed inward, thereby effectively separating it from the negative electrode tab group and making it easier to weld itself to the current collecting plate.
  • the positive electrode tabs respectively connected to each positive electrode sheet winding layer are located at the most upstream end position in the winding direction, and the negative electrode tabs respectively connected to each negative electrode sheet winding layer are located at the said winding direction.
  • the most upstream end positions in the winding direction are all located on the same plane;
  • the positive electrode tabs respectively connected to each positive electrode sheet winding layer are located at the most downstream end position in the winding direction, and the negative electrode tabs respectively connected to each negative electrode sheet winding layer are located at the most downstream end position in the winding direction.
  • the downstream end positions are all on the same plane.
  • the winding structure is a cylindrical winding structure wound around a winding axis, and the plurality of positive electrode tabs and the plurality of negative electrode tabs are symmetrical with respect to the winding axis, or Symmetrical relative to a plane passing through the winding axis.
  • multiple positive electrode tabs and multiple negative electrode tabs can be made symmetrical with respect to the winding axis, or multiple positive electrode tabs and multiple negative electrode tabs can be made Symmetry relative to the plane passing through the winding axis improves the uniformity of the welding effect through the consistency in form of the smoothed positive electrode tab group and negative electrode tab group.
  • the electrode assembly further includes: an insulator disposed at an end of the main body connecting the plurality of positive electrode tabs and the plurality of negative electrode tabs, and located on the plurality of negative electrode tabs. between the positive electrode tab and the plurality of negative electrode tabs.
  • insulators are provided between multiple positive electrode tabs and multiple negative electrode tabs to achieve effective separation between the two and reduce the occurrence of short circuits. risks of.
  • the insulating member includes an insulating plastic block.
  • the positive electrode tab and the negative electrode tab are isolated by an insulating plastic block with a certain volume.
  • the insulation between the positive electrode tab and the negative electrode tab can be effectively achieved to avoid short circuit between the two.
  • the positive electrode tab and the negative electrode tab can be effectively separated from each other.
  • the end forms a certain supporting effect, so that it can withstand a certain extrusion force when the end of the battery is pressed, reducing the risk of decarburization of the edge of the pole piece caused by pressure on the main body.
  • the winding structure is a cylindrical winding structure wound around a winding axis, the cylindrical winding structure has a first central hole penetrating along the axial direction, and the insulating member has a The first central hole is connected to a second central hole along the winding axis.
  • the perfusion of electrolyte in the battery cell can be achieved.
  • both the first central hole and the second central hole are circular holes, and the diameter D1 of the first central hole is greater than or equal to the diameter D2 of the second central hole.
  • the upstream end positions of the positive electrode tabs connected to each positive electrode sheet winding layer are all located on the first plane in the winding direction, and the positive electrode tabs connected to each positive electrode sheet winding layer are respectively connected.
  • the upstream end positions of the negative electrode tabs respectively connected to each negative electrode sheet winding layer in the winding direction are all located on the third plane, and the negative electrode tabs respectively connected to each negative electrode sheet winding layer are located in the winding direction.
  • C is the capacity of the battery using the electrode assembly
  • L is the total length of the negative electrode piece
  • K1 is the first proportional parameter
  • K2 is the second proportional parameter
  • the value of the aforementioned angle range should not be greater than 180 degrees. If it exceeds 180 degrees, it is easy for the negative pole tab or the positive pole tab to come into contact with the tab of the other polarity after it is smoothed, resulting in the risk of short circuit.
  • the angle range corresponding to the tab group, the total length of the negative electrode piece, and the battery capacity are all related to the current density flowing through the tab. When the battery capacity is constant, the longer the total length of the negative electrode piece, the corresponding to the circumference of the circle.
  • a tab group with a smaller included angle range can be used; and when the total length of the negative electrode piece is constant, the greater the battery capacity, corresponding to the circumference of the circumference The greater the unit charge, in order to prevent the current density flowing through the tabs from being too high, resulting in overcurrent and heating, a tab set with a larger included angle range can be used.
  • the unit of the capacity C of the electrode assembly is ampere-hour
  • the unit of the total length L of the negative electrode piece is millimeters
  • the first proportional parameter K1 is greater than or equal to
  • the second proportional parameter K2 is greater than or equal to
  • the temperature of the tabs can be maintained within the allowable range during charging to avoid overheating and affecting the performance of chemical substances in batteries using electrode assemblies.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode active material film layer covering the surface of the positive electrode current collector, and the plurality of positive electrode tabs are connected to the positive electrode current collector along the roll.
  • the positive active material film layer continuously extends from the surface of the positive electrode current collector to part of the surface of the plurality of positive electrode tabs, and the negative electrode tab includes a negative electrode current collector, The negative electrode active material film layer covering the surface of the negative electrode current collector and the insulating film layer covering the surface of the negative electrode current collector, the plurality of negative electrode tabs are connected to the negative electrode current collector extending along the winding direction.
  • the insulating film layer is located on the front side of the negative active material film layer in the first direction, and continuously extends from the surface of the negative electrode current collector to part of the surface of the plurality of negative electrode tabs,
  • the first direction is an extension direction of the plurality of positive electrode tabs relative to the positive electrode tab or an extension direction of the plurality of negative electrode tabs relative to the negative electrode tab, and the first direction is consistent with the extension direction of the plurality of positive electrode tabs relative to the negative electrode tab.
  • the winding direction is vertical.
  • the edge part of the positive active material film is thinner, and the thinner positive active material film may cause an excessive gap between the electrode plates, making it difficult to retain the electrolyte, resulting in poor local electrolyte infiltration effect. , the problem of lithium precipitation is prone to occur.
  • the positive electrode tab is cut out of the positive electrode piece by die cutting or other methods, by cutting off the side of the positive electrode piece with the positive active material film layer, the positive active material film layer can be formed to continuously extend from the surface of the positive electrode current collector to the positive electrode. The state of part of the surface of the positive electrode tab.
  • the thickness of the positive electrode active material film layer covered on the side of the positive electrode tab adjacent to the positive electrode tab is more consistent with other positions of the positive electrode tab, making it easier to retain electrolyte. solution to obtain better electrolyte infiltration effect and reduce the risk of lithium precipitation.
  • the edge part of the insulating film layer is thinner, and the thinner insulating film layer may cause an excessive gap between the pole pieces, which makes it difficult to retain the electrolyte, resulting in poor local electrolyte infiltration effect and prone to lithium precipitation.
  • the problem When the negative electrode tab is cut out of the negative electrode tab by die-cutting or other methods, by cutting off the side of the negative electrode tab with the insulating film layer, an insulating film layer can be formed that extends continuously from the surface of the negative electrode current collector to part of the surface of the negative electrode tab. state.
  • the thickness of the insulating film layer covered on the side of this negative electrode piece adjacent to the negative electrode tab is more consistent with other positions of the negative electrode piece, making it easier to retain the electrolyte and obtain better results.
  • the electrolyte infiltration effect reduces the risk of lithium precipitation.
  • the cathode active material film layer is located on the front side of the first side at the frontmost ends of the extended portions of the plurality of cathode tabs.
  • the first side is equivalent to the die-cut edge of the positive electrode, and the front end of the extended portion of the positive active material film layer on the positive electrode tab is equivalent to the coating film of the positive electrode. side. If the opposite side of the first side in the opposite direction to the first direction is used as a reference, the height of the coating side of the positive electrode is greater than the die-cut side of the positive electrode, so that the side outside the positive electrode tab and outside the positive electrode can be cut during die-cutting.
  • the positive electrode piece is partially cut off at a certain height below the coating edge of the positive electrode, thereby cutting off the part of the positive electrode piece corresponding to the thinned part of the edge of the positive active material film layer, which can reduce the possible electrolyte shortage problem in this part. , reduce the risk of local lithium precipitation.
  • the first side is located behind the second side in the first direction.
  • the first side is equivalent to the die-cut edge of the positive electrode
  • the second side is equivalent to the die-cut edge of the negative electrode.
  • the height of the die-cut side of the positive electrode is smaller than the height of the die-cut side of the negative electrode. In this way, when the negative electrode tab is smoothed, if the tab wrinkles are inserted in the direction of the electrode piece, the negative electrode piece will first overlap with the insulating coating on the negative electrode piece, and will not easily connect with the positive electrode piece first.
  • the positive active material film layers are overlapped to reduce the risk of short circuit.
  • the cathode active material film layer is located at the front end of the extended portion of the plurality of cathode tabs and the insulating film layer is at the front end of the extending portion of the plurality of cathode tabs. The rear side of the frontmost end of the extension.
  • the height of the coating side of the positive active material film layer on the positive electrode tab is smaller than the height of the coating side of the insulating layer on the negative electrode tab. the height of. In this way, when the end of the electrode assembly is pressurized, the insulating layer will be pressurized before the cathode active material film layer, which can reduce the risk of decarburization of the cathode active material film layer when it is pressurized, thereby causing a short circuit.
  • At least one positive electrode tab among the plurality of positive electrode tabs has at least one first notch on a side away from the positive electrode tab, and the at least one first notch connects the positive electrode tab to the side of the positive electrode tab.
  • the pole tab is divided into a plurality of positive pole tab segments along the winding direction, and the root of the at least one first notch is located on the front side of the separator in the first direction;
  • At least one negative electrode tab among the plurality of negative electrode tabs has at least one second notch on a side away from the negative electrode tab.
  • the at least one second notch connects the negative electrode tab along the roll.
  • the circumferential direction is divided into a plurality of negative electrode tab segments, and the root of the at least one second notch is located on the front side of the separator in the first direction.
  • the heights of the roots of the first notch and the roots of the second notch are greater than the height of the diaphragm. Since the root of the first notch and the root of the second notch are usually the bending and smoothing positions of the tab segment, when the tab segment is smoothed and then welded to the current collecting plate, the heated tab segment can be welded with the current collecting plate.
  • the diaphragm is kept at a certain distance, thereby reducing the possibility of the diaphragm being burned during welding, thereby preventing a short circuit caused by the diaphragm being burned.
  • the electrode assembly further includes:
  • the positive current collecting plate is located on the side of the plurality of positive electrode tabs away from the main body part, and is fixedly connected to the smoothed plurality of positive electrode tabs by welding;
  • the negative electrode current collecting plate is located on the side of the plurality of negative electrode tabs away from the main body part, and is fixedly connected to the smoothed plurality of negative electrode tabs by welding;
  • the plurality of positive electrode tabs are bent and smoothed at the root of the at least one first notch toward the end center of the main body, and the plurality of negative electrode tabs are formed at the root of the at least one second notch.
  • the root is bent and smoothed toward the end center of the main body, and a first distance d1 between the root of the at least one first notch and the separator in the first direction is greater than or equal to the positive electrode current collecting plate.
  • 1.5 times the thickness t1 and the second distance d2 between the root of the at least one second notch and the separator in the first direction is greater than or equal to 1.5 times the thickness t2 of the negative electrode current collecting plate.
  • the thickness of the current collecting plate is related to the heat during welding, the thicker the current collecting plate, the higher the heat during welding.
  • the first distance between the root of the first notch and the separator in the first direction is larger than the positive electrode current collecting plate. 1.5 times the thickness of the negative electrode current collecting plate, and making the second distance between the root of the second notch and the separator in the first direction greater than 1.5 times the thickness of the negative electrode current collecting plate, which can effectively reduce the possibility of the separator being burned when welding the current collecting plate. properties, thereby preventing the diaphragm from being burned and causing a short circuit.
  • the root of the first gap between adjacent positive electrode tab segments and the root of the second gap between adjacent negative electrode tab segments are located on the same plane perpendicular to the first direction.
  • the opposite side of the first side in the opposite direction to the first direction is used as a reference, by setting the root of the first notch and the root of the second notch at the same height, the positive electrode tab and the negative electrode tab can be arranged at the same height.
  • the flat back can be on the same plane as much as possible to ensure that welding is not prone to virtual welding.
  • the electrode assembly further includes:
  • An insulating member is provided at the end of the main body connecting the plurality of positive electrode tabs and the plurality of negative electrode tabs, and is located between the plurality of positive electrode tabs and the plurality of negative electrode tabs.
  • the distance between the root of the at least one first notch and the second side is a third distance d3, and the distance between the root of the at least one second notch and the second side
  • the distance is the fourth distance d4
  • the insulating member is located on the front side of the second side, and the distance between the frontmost end of the insulating member along the first direction and the second side is the fifth distance d5
  • the distance between the front end of the extended portion of the positive electrode active material film layer and the second side of the plurality of positive electrode tabs is the sixth distance d6, the third distance d3, the fourth distance d4.
  • the fifth distance d5 and the sixth distance d6 satisfy: d5 ⁇ d6, d3 ⁇ d5, d4 ⁇ d5.
  • the root of the first notch and the root of the second notch are further forward than the insulating member, so that when welding the current collecting plate, the current collecting plate will first contact and weld with the smoothed pole lug, so that Effectively avoid virtual soldering.
  • the front end of the insulating member in the first direction is further forward than the front end of the cathode active material film layer of the cathode tab. In this way, when the electrode assembly is pressurized, the insulating member will be pressurized before the cathode active material film layer. This reduces the risk of decarburization of the positive active material film layer when under pressure, resulting in short circuit.
  • a battery cell including the aforementioned electrode assembly. Battery cells using the aforementioned electrode assembly have better performance.
  • a battery including the aforementioned battery cell. Batteries using the aforementioned battery cells have better performance.
  • an electrical device including the aforementioned battery. Electrical devices using the aforementioned batteries have better performance.
  • a method of manufacturing an electrode assembly including:
  • a diaphragm a positive pole piece connected with a positive pole tab, and a negative pole piece connected with a negative pole tab;
  • the positive electrode tabs are die-cut into a plurality of positive electrode tabs arranged at intervals along the length direction of the positive electrode piece, and the negative electrode tabs are die-cut into pieces spaced apart along the length direction of the negative electrode piece. Multiple negative electrode tabs arranged;
  • the positive electrode tab, the separator and the negative electrode tab are rolled into a main body part of the electrode assembly, and the plurality of positive electrode tabs and the plurality of negative electrode tabs are located in the main body part.
  • the length of the positive electrode tab connected to each positive electrode tab winding layer of the main body part is along the direction of the winding direction.
  • the winding direction increases, and the length of the negative electrode tabs respectively connected to each negative electrode tab winding layer of the main body portion in the winding direction increases along the winding direction.
  • Multiple positive electrode tabs formed on the positive electrode tab and multiple negative electrode tabs formed on the negative electrode tab are arranged on the same side of the winding structure through a die-cutting process, so that the current collecting plate corresponding to the positive electrode tab and the corresponding negative electrode tab
  • the current collecting plates can respectively collect currents and output them from the same side.
  • this embodiment can shorten the electron path from the pole piece to the pole, so that the tabs do not need to be By guiding the current through the casing, the adverse effects of the casing resistance on the battery's internal resistance and the casing's heat on the battery's internal heat dissipation are eliminated, thereby reducing the battery's internal resistance, improving battery heat dissipation, and increasing battery power and fast charging capabilities.
  • each positive pole tab after the pole piece is wound can be bent and smoothed according to the corresponding pole
  • the manufacturing method further includes:
  • An insulator is fixed between the plurality of positive electrode tabs and the plurality of negative electrode tabs, so that a tab group formed by overlapping the plurality of positive electrode tabs and a tab group formed by overlapping the plurality of negative electrode tabs
  • the tab groups are isolated by the insulator.
  • the manufacturing method further includes:
  • the positive current collector plate is welded to the smoothed positive electrode tabs, and the negative electrode current collector pan is welded to the smoothed negative electrode tabs.
  • At least one positive electrode tab among the plurality of positive electrode tabs is die-cut out from the side of the side away from the positive electrode tab. At least one first notch to separate the positive electrode tab into a plurality of positive electrode tab segments along the winding direction through the at least one first notch;
  • At least one second notch is die-cutted on the side of at least one of the plurality of negative electrode tabs away from the negative electrode tab,
  • the negative electrode tab is divided into a plurality of negative electrode tab segments along the winding direction through the at least one second notch.
  • the positive electrode tab By die-cutting the first notch on the side of the positive electrode tab to obtain multiple separated positive electrode tab segments, the positive electrode tab is less likely to wrinkle when smoothed, and the risk of tab breakage and damage caused by wrinkles is reduced. There is a risk of short circuit due to the corrugated part being inserted between the pole pieces.
  • the second notch on the side of the negative electrode tab to obtain multiple separated negative electrode tab segments, the negative electrode tab is less likely to wrinkle when smoothed, and the tab caused by wrinkles is reduced. Risk of breakage and risk of crimped parts being inserted between pole pieces causing short circuit.
  • Figure 1 is a schematic structural diagram of some embodiments of an electrical device according to the present disclosure
  • Figure 2 is a schematic structural diagram of some embodiments of a battery according to the present disclosure.
  • Figure 3 is a schematic cross-sectional view of a wound structure formed according to some embodiments of an electrode assembly of the present disclosure
  • Figure 4 is an expanded schematic diagram of a positive electrode piece in some embodiments of an electrode assembly according to the present disclosure
  • Figure 5 is an expanded schematic diagram of a negative electrode piece in some embodiments of an 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.
  • Figures 7 and 8 are respectively a schematic view of the end of the embodiment of Figure 6 with an insulating member and a schematic view of the end without the insulating member from a bird's eye view;
  • Figure 9 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure.
  • Figure 10 is a schematic view of the end of the embodiment of Figure 9 with the insulating member removed from a bird's eye view;
  • Figures 11 and 12 are schematic views of the coverage range of the electrode tabs and the insulator at the end of the main body in the embodiment of Figure 6 and the embodiment of Figure 9 respectively;
  • Figure 13 is a schematic diagram of the arrangement of the positive electrode piece, the negative electrode piece and the separator in some embodiments of the electrode assembly according to the present disclosure
  • Figure 14 is a schematic structural diagram of further embodiments of an electrode assembly according to the present disclosure.
  • Figure 15 is a schematic diagram of the arrangement of the positive electrode piece, the negative electrode piece, the separator and the insulator in some embodiments of the electrode assembly according to the present disclosure
  • Figure 16 is a flow diagram of some embodiments of a method of manufacturing an electrode assembly according to the present disclosure.
  • 10 Battery cell; 10A: Positive electrode piece; 10B: Negative electrode piece; 10C: Separator; 100: Winding structure; 11: Positive electrode current collector; 12 Positive electrode active material film layer; 13: Negative electrode current collector; 14: Negative electrode Active material film layer; 15: Insulating film layer; 16: First side; 17: Second side; 18: Third side; 121: Positive electrode coating side; 151: Insulating film coating side; 153: negative electrode coating edge;
  • Negative electrode tab Inventional electrode tab
  • 31 Negative electrode tab section
  • 32 Second notch
  • 33 Root of the second notch
  • 51 Positive electrode current collecting plate
  • 52 Negative electrode current collecting plate
  • 53 First electrode terminal
  • 54 Second electrode terminal
  • connection should be understood in a broad sense.
  • it can be a fixed connection or a removable connection.
  • the electrode assembly in the cylindrical battery cell has tabs extending from both ends of the winding structure, in which the tabs extending from one end are electrically connected to the casing, and are guided by the casing and connected to the tabs extending from the other end.
  • the pole ear On the same side as the pole ear.
  • embodiments of the present disclosure provide a battery cell, a battery, an electrical device, an electrode assembly and a manufacturing method thereof, which can improve the 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 casing and a battery module.
  • the casing is used to provide a receiving space for the battery module.
  • the battery module is installed in the casing.
  • the shell 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 60 is disposed inside a vehicle 70 , and the battery 60 is disposed at the bottom, head, or tail of the vehicle.
  • the battery 60 provides power to the vehicle, for example, the battery 60 serves as the vehicle's operating power source.
  • the battery 60 can be used as a power source for new energy vehicles, ships, smart electrical cabinets and other devices.
  • the battery 60 can also be used as a power supply component to provide required electrical energy to various electrical components of the device.
  • FIG. 2 is a schematic structural diagram of some embodiments of a battery according to the present disclosure.
  • the battery 60 includes a case 61 , a cover 62 , and one or more battery cells 10 disposed in the case 61 .
  • Each battery cell 10 is electrically connected, such as in series, parallel or mixed connection, to achieve the required electrical performance parameters of the battery 60 .
  • a plurality of battery cells 10 are arranged in rows, and one or more rows of battery cells 10 can be arranged in the box as needed.
  • the battery cells 10 of the battery 60 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 10 can be provided according to actual needs. If necessary, one or more layers of battery cells 10 may also be provided in the height direction of the battery 60 .
  • multiple battery cells 10 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 61 . In other embodiments, all the battery cells 10 are directly connected in series or in parallel or mixed together, and then the entire battery cell 10 is accommodated in the box.
  • the battery cell 10 may include a case, an end cap, and an electrode assembly.
  • the housing has a cavity for accommodating the electrode assembly, and an end of the housing may be configured to be open for disposing an end cap assembly.
  • the electrode assembly is installed in the cavity of the housing.
  • the battery cell 10 also includes an electrolyte.
  • FIG. 3 is a schematic cross-sectional view of a rolled structure formed in accordance with some embodiments of the disclosed electrode assembly.
  • 4 is an expanded schematic diagram of a positive electrode tab in some embodiments of an electrode assembly according to the present disclosure.
  • Figure 5 is an expanded schematic diagram of a negative electrode tab in some embodiments of an 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.
  • the electrode assembly includes: a main body 100 , a plurality of positive electrode tabs 20 and a plurality of negative electrode tabs 30 .
  • the main body 100 includes a positive electrode piece 10A, a negative electrode piece 10B, and a separator 10C provided between the positive electrode piece 10A and the negative electrode piece 10B.
  • the positive electrode piece 10A, the separator 10C and the negative electrode piece 10B are wound along the winding direction r and form a winding structure, for example, forming the negative electrode piece 10B formed along the radial direction of the winding mechanism in Figure 3.
  • the winding structure can form a cylindrical winding structure after winding.
  • 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.
  • a plurality of positive electrode tabs 20 are respectively connected to at least two positive electrode sheet winding layers in the winding structure, and are arranged at intervals along the winding direction r.
  • a plurality of negative electrode tabs 30 are respectively connected to at least two negative electrode tab winding layers in the winding structure, and are arranged at intervals along the winding direction r.
  • the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs 30 are located at the same end of the main body 100 in a direction perpendicular to the winding direction r.
  • this embodiment can shorten the electron path from the pole piece to the pole, so that the tabs do not need to guide the current through the housing, eliminating the need for It eliminates the adverse effects of case resistance on battery internal resistance and case heat on battery internal heat dissipation, thereby reducing battery internal resistance, improving battery heat dissipation, and increasing battery power and fast charging capabilities.
  • the length b1 of the positive electrode tab 20 in the winding direction r that is connected to each positive electrode tab winding layer increases along the winding direction r, and is connected to each negative electrode tab winding layer respectively.
  • the length b2 of the connected negative electrode tab 30 in the winding direction r increases along the winding direction r.
  • each positive pole tab after the pole piece is wound can be bent and smoothed according to the corresponding pole
  • Figures 7 and 8 are respectively a schematic view of the end of the embodiment of Figure 6 with an insulating member and a schematic view of the end without the insulating member from a bird's eye view.
  • Figure 9 is a schematic structural diagram of another embodiment of an electrode assembly according to the present disclosure.
  • FIG. 10 is a schematic view of the end of the embodiment of FIG. 9 with the insulating member removed from a top view.
  • 11 and 12 are schematic diagrams of the coverage range of the electrode tabs and the insulator at the end of the main body in the embodiment of FIG. 6 and the embodiment of FIG. 9 respectively.
  • the winding structure is a cylindrical winding structure wound around the winding axis ax.
  • the positive electrode tab and the negative electrode tab are located on the same side of the cylindrical winding structure. , can effectively reduce the internal resistance of the battery and improve the heat dissipation of the battery.
  • the circumference of the pole piece winding layer of the cylindrical winding structure gradually decreases from the outside to the inside, the length of the tab corresponding to each layer also decreases. , so that each layer of tabs will be more aligned after being smoothed toward the center of the circle, which facilitates separation of the positive and negative electrodes and facilitates subsequent tab welding.
  • the spacing between the pole tabs connected by each pole piece winding layer can enable the winding of the positive pole tab and the negative pole tab to be partitioned, reducing the inefficiency of the two pole piece groups with opposite polarity after smoothing. Risk of short circuit due to separation.
  • the angle range of the plurality of positive electrode tabs 20 at the end of the main body part 100 relative to the winding axis ax is the same as the angle range of the plurality of negative electrode tabs 30 at the end of the main body part 100 .
  • the angular ranges of the ends 100 relative to the winding axis ax do not coincide.
  • the electrode assembly further includes an insulator 40.
  • the insulating member 40 is provided at an end of the main body 100 connecting the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs 30, and is located between the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs. Between the extreme ears 30. In this way, by arranging insulators between the plurality of positive electrode tabs and the plurality of negative electrode tabs, the two are effectively separated and the risk of short circuit is reduced.
  • the insulating member 40 includes an insulating plastic block.
  • the shape and size of the insulating plastic hole can be determined according to the coverage of the positive and negative poles.
  • the positive electrode tab and the negative electrode tab are isolated by an insulating plastic block with a certain volume.
  • the insulation between the positive electrode tab and the negative electrode tab can be effectively achieved to avoid short circuit between the two.
  • the positive electrode tab and the negative electrode tab can be effectively separated from each other.
  • the end forms a certain supporting effect, so that it can withstand a certain extrusion force when the end of the battery is pressed, reducing the risk of decarburization of the edge of the pole piece caused by pressure on the main body.
  • the cylindrical winding structure wound around the winding axis ax, referring to Figures 7 and 8, in some embodiments, the cylindrical winding structure has a first central hole 110 that passes through in the axial direction, so The insulating member 40 has a second central hole 41 connected with the first central hole 110 along the winding axis ax.
  • both the first central hole 110 and the second central hole 41 are circular holes, and the diameter D1 of the first central hole 110 is greater than or equal to the diameter D2 of the second central hole 41 .
  • the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs 30 satisfy at least one of the following: the positive electrode tabs 20 are respectively connected to each positive electrode sheet winding layer.
  • the upstream end positions in the winding direction r are all located on the same plane (for example, the first plane S1); the positive electrode tabs 20 respectively connected to each positive electrode sheet winding layer are located in the winding direction r.
  • the most downstream end positions are all located on the same plane (for example, the second plane S2); the upstream end positions of the negative electrode tabs 30 connected to each negative electrode tab winding layer in the winding direction r are all located on the same plane.
  • plane for example, the third plane S3; the most downstream end positions of the negative electrode tabs 30 connected to each negative electrode tab winding layer in the winding direction r are all located on the same plane (for example, the fourth plane S4).
  • This embodiment aligns the upstream end positions of the positive electrode tabs connected to each positive electrode sheet winding layer to the same plane in the winding direction, which is conducive to ensuring that the side ends are smoothed inward when the positive electrode tabs of each layer are smoothed inward.
  • the neatness of the parts facilitates the separation of the positive and negative electrodes and facilitates subsequent tab welding.
  • aligning the most downstream end of the positive electrode tab to the same plane, aligning the most upstream end of the negative electrode tab to the same plane, and aligning the most downstream end of the negative electrode tab to the same plane can ensure that the end of the corresponding side is aligned. Neat, easy to separate the positive and negative electrodes, and facilitate subsequent tab welding.
  • the upstream end position and the most downstream end position of the cathode tabs 20 connected to each cathode tab winding layer in the winding direction r are located at the same position. Planes, for example, the first plane S1 and the second plane S2 are coplanar.
  • an overall arcuate positive electrode tab group can be formed. , this bow-shaped positive electrode tab group can keep both ends neat after being smoothed inward, thereby effectively separating it from the negative electrode tab group, and also facilitating the welding of itself to the current collecting plate.
  • the upstream end position and the most downstream end position of the negative electrode tabs 30 connected to each negative electrode tab winding layer in the winding direction r are both located on the same plane, such as the third plane S3 Coplanar with the fourth plane S4.
  • an overall arcuate negative electrode tab group can be formed. , this bow-shaped negative electrode tab group can keep both ends neat after being smoothed inward, thereby effectively separating it from the negative electrode tab group, and also facilitating the welding of itself to the current collecting plate.
  • the positive electrode tab 20 to which each positive electrode sheet winding layer is connected is located at the most upstream end position in the winding direction r and each negative electrode sheet winding layer is connected to each other.
  • the upstream end positions of the negative electrode tab 30 in the winding direction r are all located on the same plane, for example, the first plane S1 and the third platform S3 are coplanar.
  • the positive electrode tabs 20 connected to each positive electrode tab winding layer are located at the most downstream end position in the winding direction r, and the negative electrode tabs 30 connected to each negative electrode tab winding layer are located in the winding direction r.
  • the most downstream end positions on r are all located on the same plane, for example, the second plane S2 and the fourth platform S4 are coplanar.
  • the positive electrode tabs connected to each positive electrode sheet winding layer are located at the most upstream end in the winding direction, and the negative electrode tabs connected to each negative electrode sheet winding layer are located at the most downstream end.
  • the positions are aligned to the same plane, and the positive electrode tabs connected to each positive electrode sheet winding layer are located at the most downstream end position in the winding direction, and the negative electrode tabs connected to each negative electrode sheet wound layer are located at the most upstream end.
  • the end positions are aligned to the same plane, which can form a positive electrode tab group and a negative electrode tab group that are overall fan-shaped and symmetrical to each other.
  • the tab group of this structure has good consistency, and it is easier to maintain the welding effect during welding. Uniformity.
  • the plurality of The positive electrode tab 20 and the plurality of negative electrode tabs 30 are symmetrical with respect to the winding axis ax, or symmetrical with respect to a plane passing through the winding axis ax. In this way, the uniformity of the welding effect is improved through the consistency in shape of the smoothed positive electrode tab group and the negative electrode tab group.
  • the upstream end positions of the cathode tabs 20 connected to each cathode tab winding layer in the winding direction r are located on the first plane S1
  • each The most downstream end positions of the positive electrode tabs 20 respectively connected to the positive electrode sheet winding layer in the winding direction r are located on the second plane S2, and the first plane S1 reaches the second plane in the circumferential direction
  • C is the capacity of the battery using the electrode assembly
  • L is the total length of the negative electrode piece 10B
  • K1 is the first proportional parameter.
  • the upstream end positions of the negative electrode tabs 30 connected to each negative electrode sheet winding layer are all located on the third plane S3 in the winding direction r.
  • the negative electrode tabs 30 connected to each negative electrode sheet winding layer are respectively connected.
  • the most downstream end positions in the winding direction r are all located on the fourth plane S4.
  • C is the capacity of the battery using the electrode assembly
  • L is the total length of the negative electrode piece 10B
  • K2 is the second proportion parameter.
  • the value of the aforementioned angle range should not be greater than 180 degrees. If it exceeds 180 degrees, it is easy for the negative pole tab or the positive pole tab to come into contact with the tab of the other polarity after it is smoothed, resulting in the risk of short circuit.
  • the angle range corresponding to the tab group, the total length L of the negative electrode piece, and the battery capacity C are all related to the current density flowing through the tab.
  • the capacity C of the electrode assembly is in ampere-hour
  • the total length L of the negative electrode piece 10B is in millimeters
  • the first proportional parameter K1 is greater than or equal to
  • the second proportional parameter K2 is greater than or equal to
  • the electrode assembly when the electrode assembly is used in a lithium secondary battery, since the lithium salt, solvent, positive active material, and negative active material may undergo accelerated side reactions or even decompose at high temperatures, the electrode assembly is usually in normal use. It should be controlled below 80°C, preferably below 60°C. In an experimental example, the capacity C of the battery component is 45 ampere hours, and the total length L of the negative electrode piece is 4827mm. According to Doing the calculations, ⁇ 1 and ⁇ 2 are both approximately equal to 112 degrees.
  • the actual included angle range ⁇ 1 and ⁇ 2 is 120 degrees which is greater than 112 degrees, the corresponding K1 and K2 are greater than
  • the measured pole root temperature during fast charging is 50°C, which meets the requirements for this type of battery pole temperature to be lower than 60°C and 80°C.
  • the capacity C of the battery component is 32.5 ampere hours, and the total length L of the negative electrode plate is 4585mm.
  • ⁇ 1 and ⁇ 2 are both approximately equal to 85 degrees. Therefore, when the actual included angle range ⁇ 1 and ⁇ 2 is 90 degrees greater than 85 degrees, the corresponding K1 and K2 are greater than
  • the measured tab root temperature during fast charging is 52°C, which meets the requirements for this type of battery tab temperature to be lower than 60°C and 80°C.
  • the capacity C of the battery component is 30 ampere hours, and the total length L of the negative electrode plate is 4585mm.
  • ⁇ 1 and ⁇ 2 are both approximately equal to 78 degrees. Therefore, when the actual included angle range ⁇ 1 and ⁇ 2 is 30 degrees which is less than 78 degrees, the corresponding K1 and K2 are less than
  • the measured pole root temperature during fast charging is 80°C, which does not meet the requirements for this type of battery pole temperature to be lower than 60°C and 80°C.
  • Figure 13 is a schematic diagram of the arrangement of the positive electrode piece, the negative electrode piece and the separator in some embodiments of the electrode assembly according to the present disclosure.
  • at least one positive electrode tab 20 among the plurality of positive electrode tabs 20 has at least one first notch 22 on the side away from the side of the positive electrode tab 10A, The at least one first notch 22 divides the positive electrode tab 20 into a plurality of positive electrode tab segments 21 along the winding direction r.
  • the positive electrode tab is less likely to wrinkle when smoothed, and the risk of tab breakage and wrinkles caused by wrinkles is reduced. Risk of short circuit caused by partial insertion between pole pieces.
  • At least one negative electrode tab 30 among the plurality of negative electrode tabs 30 may have at least one second notch 32 on a side away from the negative electrode tab 10B.
  • the at least one second notch 32 connects the negative electrode to the side of the negative electrode tab 10B.
  • the tab 30 is divided into a plurality of negative electrode tab segments 31 along the winding direction r. By setting a second notch on the side of the negative electrode tab to obtain multiple separated negative electrode tab segments, the negative electrode tab is less likely to wrinkle when smoothed, reducing the risk of tab breakage and wrinkles caused by wrinkles. Risk of short circuit caused by partial insertion between pole pieces.
  • the positive electrode tab may not have a first notch, and may be continuous in the winding direction r without being divided into multiple positive electrode tab segments; the negative electrode tab may also not have a second notch, and may be continuous in the winding direction r. Continuous without being divided into multiple negative electrode tab segments.
  • the width of each positive electrode tab segment 21 in the winding direction r is the same, and the number of positive electrode tab segments 21 in the positive electrode tab 20 connected to each positive electrode tab winding layer can be increases along the winding direction r.
  • the number of positive electrode tab segments 21 corresponding to the inner positive electrode sheet winding layer is less than the number of positive electrode tab segments 21 corresponding to the outer positive electrode sheet winding layer, and the change in this number may be continuous. , it can also change according to stages.
  • Using positive electrode tab segments 21 with the same width can reduce the processing difficulty of the positive electrode tab and make the smoothed positive electrode tab group more neat.
  • the positive electrode tab segments 21 are connected through each positive electrode sheet winding layer. The change in the number will realize the corresponding change in the length b1 of the positive electrode tab.
  • Each negative electrode tab segment 31 has the same width in the winding direction r, and the number of negative electrode tab segments 31 in the negative electrode tab 30 respectively connected to each negative electrode tab winding layer is along the winding direction r. Increase. For example, the number of negative electrode tab segments 31 corresponding to the inner negative electrode sheet winding layer is less than the number of negative electrode tab segments 31 corresponding to the outer negative electrode sheet winding layer. This change in number may be continuous. , it can also change according to stages. Using negative electrode tab segments 31 with the same width can reduce the processing difficulty of the negative electrode tab and make the smoothed negative electrode tab group more neat. Correspondingly, the negative electrode tab segments 31 are connected through each negative electrode sheet winding layer. The change in quantity realizes the corresponding change in the length b2 of the negative electrode tab.
  • the positive electrode sheet 10A includes a positive current collector 11 and a positive active material film layer 12 covering the surface of the positive current collector 11 .
  • the plurality of positive electrode tabs 20 are connected to the first side 16 of the positive electrode current collector 11 extending along the winding direction r.
  • the positive active material film layer 12 continuously extends from the surface of the positive current collector 11 to part of the surfaces of the plurality of positive tabs 20 .
  • the material of the cathode current collector 11 can be aluminum, and the cathode active material film layer 12 can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganate.
  • a plurality of positive electrode tabs 20 may be welded to the first side of the positive electrode current collector 11 .
  • the plurality of positive electrode tabs 20 may also be formed by die-cutting the positive electrode current collector 11 .
  • the edge part of the positive active material film is thinner, and the thinner positive active material film may cause an excessive gap between the electrode plates, making it difficult to retain the electrolyte, resulting in poor local electrolyte infiltration effect. , the problem of lithium precipitation is prone to occur.
  • the positive electrode tab is cut out of the positive electrode piece by die cutting or other methods, by cutting off the side of the positive electrode piece with the positive active material film layer, the positive active material film layer can be formed to continuously extend from the surface of the positive electrode current collector to the positive electrode. The state of part of the surface of the positive electrode tab.
  • the thickness of the positive electrode active material film layer covered on the side of the positive electrode tab adjacent to the positive electrode tab is more consistent with other positions of the positive electrode tab, making it easier to retain electrolyte. solution to obtain better electrolyte infiltration effect and reduce the risk of lithium precipitation.
  • the negative electrode sheet 10B includes a negative electrode current collector 13 , a negative electrode active material film layer 14 covering the surface of the negative electrode current collector 13 , and an insulating film layer 15 covering the surface of the negative electrode current collector 13 .
  • the plurality of negative electrode tabs 30 are connected to the second side 17 of the negative electrode current collector 13 extending along the winding direction r.
  • the insulating film layer 15 (such as a ceramic insulating layer, etc.) is located on the front side of the negative active material film layer 14 in the first direction a, and continuously extends from the surface of the negative electrode current collector 13 to the plurality of negative electrodes. part of the surface of the ear 30.
  • the insulating layer 15 can prevent burrs on the cut edge of the anode pole from piercing the separator and causing a short circuit with the cathode pole.
  • the negative electrode current collector 13 may be made of copper, and the negative electrode active material film layer 14 may be made of carbon or silicon.
  • a plurality of negative electrode tabs 30 may be welded to the second side 17 of the negative electrode current collector 13 .
  • the plurality of negative electrode tabs 30 may also be formed by die-cutting the negative electrode current collector 13 .
  • the first direction a is the extension direction of the plurality of positive electrode tabs 20 relative to the positive electrode tab 10A or the extension direction of the plurality of negative electrode tabs 30 relative to the negative electrode tab 10B, and
  • the first direction is perpendicular to the winding direction r.
  • the edge part of the insulating film layer is also thinner, and the thinner insulating film layer may cause an excessive gap between the electrode plates, making it difficult to deposit Retention of electrolyte results in poor local electrolyte infiltration effect and prone to lithium precipitation.
  • an insulating film layer can be formed that extends continuously from the surface of the negative electrode current collector to part of the surface of the negative electrode tab. state.
  • the thickness of the insulating film layer covered on the side of this negative electrode piece adjacent to the negative electrode tab is more consistent with other positions of the negative electrode piece, making it easier to retain the electrolyte and obtain better results.
  • the electrolyte infiltration effect reduces the risk of lithium precipitation.
  • the cathode active material film layer 12 is located on the front side of the first side 16 at the frontmost ends of the extended portions of the cathode tabs 20 .
  • the first side 16 is equivalent to the die-cut edge of the positive electrode tab 10A, and the front end of the extension portion of the positive electrode active material film layer 12 on the positive electrode tab 20 It is defined as the positive electrode coating edge 121.
  • the height of the positive electrode coating edge 121 is greater than the die-cut edge of the positive electrode piece 10A, so that it can be connected with the positive electrode during die-cutting.
  • the portion of the positive electrode piece outside the pole lug and below a certain height of the positive electrode coating edge 121 is cut off, thereby cutting off the portion of the positive electrode piece corresponding to the thinned portion of the edge of the positive electrode active material film layer, which can reduce the possible risk of this part Solve the problem of electrolyte shortage and reduce the risk of local lithium precipitation.
  • the first side 16 in the first direction a, is located behind the second side 17 .
  • the first side 16 is equivalent to the die-cut edge of the positive electrode tab 10A
  • the second side 17 is equivalent to the die-cut edge of the negative electrode tab 10B.
  • the height of the die-cut edge of the positive electrode piece is smaller than the height of the die-cut side of the negative electrode piece.
  • the negative electrode tab when the negative electrode tab is smoothed, if the tab wrinkles are inserted in the direction of the electrode piece, the negative electrode piece will first overlap with the insulating coating on the negative electrode piece, and will not easily connect with the positive electrode piece first.
  • the positive active material film layers are overlapped to reduce the risk of short circuit.
  • the positive electrode active material film layer 12 is located at the front end of the extended portion of the plurality of positive electrode tabs 20 and the insulating film layer 15 is located at the front end of the extended portion of the plurality of negative electrode tabs 20 .
  • the rear side of the frontmost end of the extended portion of the pole lug 30 is defined as the positive electrode coating edge 121, and the front end of the extended portion of the insulating film layer 15 on the negative electrode tab 30 is defined as the insulating film layer coating edge. 151.
  • the height of the positive electrode coating side 121 is smaller than the height of the insulation film coating side 151 . In this way, when the end of the electrode assembly is pressurized, the insulating layer will be pressurized before the cathode active material film layer, which can reduce the risk of decarburization of the cathode active material film layer when it is pressurized, thereby causing a short circuit.
  • At least one positive electrode tab 20 among the plurality of positive electrode tabs 20 has at least one first notch 22 on a side away from the side of the positive electrode tab 10A, and the at least one first notch 22 divides the positive electrode tab 20 into a plurality of positive electrode tab segments 21 along the winding direction r, and the root 23 of the at least one first notch 22 is located in front of the separator 10C in the first direction. side.
  • At least one negative electrode tab 30 among the plurality of negative electrode tabs 30 has at least one second notch 32 on the side away from the negative electrode tab 10B. The at least one second notch 32 connects the negative electrode tab 30 to the negative electrode tab 10B.
  • the ear 30 is divided into a plurality of negative electrode ear segments 31 along the winding direction r, and the root 33 of the at least one second notch 32 is located on the front side of the separator 10C in the first direction.
  • the height of the root of the first notch and the root of the second notch is greater than the height of the diaphragm. Since the root of the first notch and the root of the second notch are usually the bending and smoothing positions of the tab segment, when the tab segment is smoothed and then welded to the current collecting plate, the heated tab segment can be welded with the current collecting plate.
  • the diaphragm is kept at a certain distance, thereby reducing the possibility of the diaphragm being burned during welding, thereby preventing a short circuit caused by the diaphragm being burned.
  • FIG. 14 is a schematic structural diagram of further embodiments of an electrode assembly according to the present disclosure.
  • the electrode assembly further includes: a positive electrode current collecting plate 51 and a negative electrode current collecting plate 52 .
  • the positive current collecting plate 51 is located on the side of the positive electrode tabs 20 away from the main body 100 , and is fixedly connected to the smoothed positive electrode tabs 20 by welding.
  • the negative electrode current collecting plate 52 is located on the side of the plurality of negative electrode tabs 30 away from the main body 100 , and is fixedly connected to the smoothed plurality of negative electrode tabs 30 by welding.
  • FIG. 14 the electrode assembly further includes: a positive electrode current collecting plate 51 and a negative electrode current collecting plate 52 .
  • the positive current collecting plate 51 is located on the side of the positive electrode tabs 20 away from the main body 100 , and is fixedly connected to the smoothed positive electrode tabs 20 by welding.
  • the negative electrode current collecting plate 52 is located on the side of the plurality of negative electrode tabs 30 away from the main body
  • the positive current collecting plate 51 may be electrically connected to any one of the first electrode terminal 53 and the second electrode terminal 54
  • the negative electrode current collecting plate 52 may be electrically connected to either of the first electrode terminal 53 and the second electrode terminal 54 . of another electrical connection.
  • the plurality of positive electrode tabs 20 are bent and smoothed at the root 23 of the at least one first notch 22 toward the end center of the main body 100 , and the plurality of negative electrode tabs 30 are located there.
  • the root 33 of the at least one second notch 32 is bent and smoothed toward the end center of the main body 100 .
  • the first distance d1 in the first direction a between the root 23 of the at least one first notch 22 and the separator 10C is greater than or equal to the positive electrode current collecting plate 51 1.5 times the thickness of t1, that is, d1 ⁇ 1.5*t1.
  • the second distance d2 in the first direction a between the root 33 of the at least one second notch 32 and the separator 10C is greater than or equal to the negative electrode current collecting plate 52 1.5 times the thickness t2, that is, d2 ⁇ 1.5*t2.
  • the thickness of the current collecting plate is related to the heat during welding, the thicker the current collecting plate, the higher the heat during welding.
  • the first distance between the root of the first notch and the separator in the first direction is larger than the positive electrode current collecting plate. 1.5 times the thickness, and making the second distance between the root of the second notch and the separator in the first direction greater than 1.5 times the thickness of the negative electrode current collecting plate, which can effectively reduce the possibility of the separator being burned when welding the current collecting plate. , thereby preventing the diaphragm from being burned and causing a short circuit.
  • the root of the first gap 22 between adjacent positive electrode tab segments 21 and the root of the second gap 32 between adjacent negative electrode tab segments 31 are located on the same plane perpendicular to the first direction. If the opposite side of the first side 16 in the opposite direction to the first direction a is used as a reference, by arranging the root 23 of the first notch 22 and the root 33 of the second notch 32 at the same height, the positive electrode tab can be The negative electrode tab and the negative electrode tab should be in the same plane as possible when welding after smoothing, so as to ensure that welding is not prone to virtual welding.
  • Figure 15 is a schematic diagram of the arrangement of the positive electrode piece, the negative electrode piece, the separator and the insulator in some embodiments of the electrode assembly according to the present disclosure.
  • Figure 15 schematically depicts the position of the insulating member 40 relative to the unfolded positive electrode tab 10A, negative electrode tab 10B and separator 10C. It can be seen that the insulating member 40 is located between the positive electrode tab 20 and the negative electrode tab 30. And in the first direction a, the distance between the root 23 of the at least one first notch 22 and the second side 17 is a third distance d3, and the distance between the root 33 of the at least one second notch 32 and the second side 17 is a third distance d3. The distance between the second side 17 is the fourth distance d4.
  • the insulating member 40 is located on the front side of the second side 17 , and the distance between the frontmost end 42 of the insulating member 40 and the second side 17 is the fifth distance d5.
  • the distance between the front end of the extended portion of the positive electrode tabs 20 (that is, the positive electrode coating edge 121 ) of the positive active material film layer 12 and the second side 17 is a sixth distance d6 .
  • the third distance d3, the fourth distance d4, the fifth distance d5 and the sixth distance d6 satisfy: d5 ⁇ d6, d3 ⁇ d5, d4 ⁇ d5.
  • the root of the first notch and the root of the second notch are further forward than the insulating member, so that when welding the current collecting plate, the current collecting plate will first contact and weld with the smoothed pole lug, so that Effectively avoid virtual soldering.
  • the front end of the insulating member in the first direction is further forward than the front end of the cathode active material film layer of the cathode tab. In this way, when the electrode assembly is pressurized, the insulating member will be pressurized before the cathode active material film layer. This reduces the risk of decarburization of the positive active material film layer when under pressure, resulting in short circuit.
  • FIG. 16 is a flow diagram of some embodiments of a method of manufacturing an electrode assembly according to the present disclosure.
  • the aforementioned embodiment of the electrode assembly can be obtained by the manufacturing method shown in FIG. 16 .
  • the manufacturing method of the electrode assembly includes: step S1, step S2, step S3 and step S4.
  • step S1 a separator 10C, a positive electrode tab 10A connected with all positive tabs, and a negative tab 10B connected with all negative tabs are provided.
  • the positive electrode piece 10A and the negative electrode piece 10B can be obtained by processes such as pulping, coating, rolling and slitting.
  • step S2 the positive electrode tabs are die-cut into a plurality of positive electrode tabs 20 arranged at intervals along the length direction of the positive electrode piece 10A, and the negative electrode tabs are die-cut into a plurality of cathode tabs 20 arranged along the length direction of the positive electrode piece 10A.
  • a plurality of negative electrode tabs 30 are arranged at intervals in the length direction of the negative electrode piece 10B. The die-cutting of positive all-pole tabs and negative all-pole tabs can be carried out using tab die-cutting equipment.
  • the length b1 of the positive electrode tab 20 connected to each positive electrode tab winding layer of the main body 100 in the winding direction r is determined. Increase along the winding direction r, and make the length b2 of the negative electrode tab 30 respectively connected to each negative electrode tab winding layer of the main body 100 in the winding direction r increase along the winding direction r. .
  • step S3 the positive electrode tab 10A, the separator 10C and the negative electrode tab 10B are wound into the main body part 100 of the electrode assembly, and the plurality of positive electrode tabs 20 and the plurality of positive electrode tabs 20 are The negative electrode tabs 30 are located at the same end of the main body 100 in a direction perpendicular to the winding direction r of the main body 100 .
  • the positive electrode tab 20 and the negative electrode tab 30 are staggered from each other so that they are located in different areas at the end of the main body 100 .
  • step S4 the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs 30 are bent and smoothed so that the plurality of positive electrode tabs 20 overlap each other and the plurality of negative electrode tabs 30 overlap each other. Stack.
  • a plurality of positive electrode tabs formed on the positive electrode tab and a plurality of negative electrode tabs formed on the negative electrode tab are arranged on the same side of the winding structure through a die-cutting process, so that the current collecting plates corresponding to the positive electrode tabs
  • the current collecting plates corresponding to the negative electrode tabs can respectively collect currents and output them from the same side.
  • this embodiment can shorten the electron flow from the pole piece to the pole.
  • each positive pole tab after the pole piece is wound can be bent and smoothed according to the corresponding pole
  • the manufacturing method further includes: step S5.
  • Step S5 may be performed after step S4.
  • the positive electrode current collecting plate 51 is welded to the smoothed plurality of positive electrode tabs 20
  • the negative electrode current collecting tray 52 is welded to the smoothed plurality of negative electrode tabs 30 .
  • Component structure is provided in step S4.
  • the manufacturing method further includes: fixing the insulator 40 between the plurality of positive electrode tabs 20 and the plurality of negative electrode tabs 30 so that the plurality of positive electrode tabs 20 overlap to form The tab group formed by overlapping the plurality of negative electrode tabs 30 is isolated by the insulator 40 .
  • the insulator 40 by arranging insulators between the plurality of positive electrode tabs and the plurality of negative electrode tabs located on the same side of the main body, effective separation between the two can be achieved, further reducing the risk of short circuits.
  • the step of arranging the insulator may be performed before step S4 to prevent the smoothed positive electrode piece and the smoothed negative electrode piece from contacting each other and causing a short circuit.
  • At least one of the plurality of positive electrode tabs 20 is moved away from the side of the positive electrode piece 10A.
  • At least one first notch 22 is cut by the side die, so that the positive electrode tab 20 is divided into a plurality of positive electrode tab segments 21 along the winding direction r through the at least one first notch 22 .
  • At least one negative electrode tab 30 of the plurality of negative electrode tabs 30 is moved away from the side of the negative electrode tab 10B.
  • At least one second notch 32 is cut by the side die, so that the negative electrode tab 30 is divided into a plurality of negative electrode tab segments 31 along the winding direction r through the at least one second notch 32 .
  • embodiments of the present disclosure also provide a battery cell, including the aforementioned electrode assembly.
  • Battery cells using the aforementioned electrode components have better performance, such as lower internal resistance, better heat dissipation, and better cycle performance.
  • a battery including the aforementioned battery cell.
  • Batteries using the aforementioned battery cells have better performance, such as lower internal resistance, better heat dissipation, and better cycle performance.
  • an electrical device including the aforementioned battery. Electrical devices using the aforementioned batteries have better performance.

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Abstract

一种电池单体、电池、用电设备、电极组件及其制造方法。电极组件包括：主体部(100)，包括正极极片(10A)、负极极片(10B)和隔膜(10C)，正极极片(10A)、隔膜(10C)和负极极片(10B)沿卷绕方向(r)卷绕为卷绕结构；多个正极极耳(20)，分别与至少两个正极极片卷绕层连接，并沿卷绕方向(r)间隔排布；多个负极极耳(30)，分别与至少两个负极极片卷绕层连接，并沿卷绕方向(r)间隔排布。多个正极极耳(20)和多个负极极耳(30)位于主体部(100)在与卷绕方向(r)垂直的方向上的同一侧端部，与各个正极极片卷绕层分别连接的正极极耳(20)和与各个负极极片卷绕层分别连接的负极极耳(30)在卷绕方向(r)的长度均沿卷绕方向(r)增加。

Description

电池单体、电池、用电设备、电极组件及其制造方法 技术领域
本公开涉及电池技术领域，特别是涉及一种电池单体、电池、用电设备、电极组件及其制造方法。
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或安全问题。
发明内容
在本公开的一个方面，提供一种电极组件，包括：
主体部，包括正极极片、负极极片和设置在所述正极极片和所述负极极片之间的隔膜，所述正极极片、所述隔膜和所述负极极片沿卷绕方向卷绕为卷绕结构；
多个正极极耳，分别与所述卷绕结构中的至少两个正极极片卷绕层连接，并沿所述卷绕方向间隔排布；和
多个负极极耳，分别与所述卷绕结构中的至少两个负极极片卷绕层连接，并沿所述卷绕方向间隔排布；
其中，所述多个正极极耳和所述多个负极极耳位于所述主体部在与所述卷绕方向垂直的方向上的同一侧端部，与各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向的长度沿所述卷绕方向增加，与各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向的长度沿所述卷绕方向增加。
将正极极片连接的多个正极极耳和负极极片连接的多个负极极耳设置在卷绕结构的同侧，这样正极极耳对应的集流盘和负极极耳对应的集流盘可分别汇集电流从同侧输出，相比于相关技术中在卷绕结构两端伸出极耳的结构，本实施例可以缩短通过极片到极柱的电子路径，使极耳无需经壳体引导电流，省去了壳体电阻对电池内阻的 不利影响和壳体发热对电池内部散热的不利影响，从而降低电池内阻，改善电池散热，提升电池功率和快充能力。
通过使各层极片卷绕层所连接的正极极耳和负极极耳的长度沿卷绕方向增加，可使得极片卷绕后的各个正极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，以及使极片卷绕后的各个负极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，从而分别形成更齐整的正极极耳组和负极极耳组，便于分隔正负极，并有利于后续的极耳焊接，并且相互隔开的正极极耳以及相互隔开的负极极耳在弯折抚平时不容易产生皱褶，从而降低极耳破碎或皱褶插入极片带来短路的风险。
在一些实施例中，所述卷绕结构为绕卷绕轴线卷绕的圆柱形卷绕结构。
相比于相关技术中圆柱电池所采用的圆柱形卷绕结构在两端分别伸出正极极耳和负极极耳，本实施例中正极极耳和负极极耳位于圆柱形卷绕结构的同侧，可以有效地降低电池内阻，改善电池散热，而且随着圆柱形卷绕结构从外到内的极片卷绕层的周长逐渐减小，各层对应的极耳长度也随之减小，这样各层极耳在向圆心方向抚平后会更加齐整，便于分隔正负极，并有利于后续的极耳焊接。另外，通过各个极片卷绕层分别连接的极耳之间的间隔可以使卷绕后的正极极耳和负极极耳能够实现分区，降低抚平后极性相反的两个极片组未有效分隔而导致短路的风险。
在一些实施例中，所述多个正极极耳在所述主体部的端部相对于所述卷绕轴线的角度范围与所述多个负极极耳在所述主体部的端部相对于所述卷绕轴线的角度范围不重合。
通过使圆柱形卷绕结构同侧的多个正极极耳和多个负极极耳的角度范围不相重合，可有效地降低抚平后极性相反的两个极片组未有效分隔而导致短路的风险。
在一些实施例中，所述多个正极极耳中的至少一个正极极耳在远离所述正极极片一侧的侧边具有至少一个第一缺口，所述至少一个第一缺口将所述正极极耳沿所述卷绕方向分隔为多个正极极耳段；和/或所述多个负极极耳中的至少一个负极极耳在远离所述负极极片一侧的侧边具有至少一个第二缺口，所述至少一个第二缺口将所述负极极耳沿所述卷绕方向分隔为多个负极极耳段。
通过将正极极耳的侧边设置第一缺口来获得分隔的多个正极极耳段可以使正极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。同样的，通过将负极极耳的侧边设置第二缺口来获得分隔的多个 负极极耳段可以使负极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
在一些实施例中，各个正极极耳段在所述卷绕方向上的宽度均相同，与各个正极极片卷绕层分别连接的正极极耳中的正极极耳段的数量沿所述卷绕方向增加；各个负极极耳段在所述卷绕方向上的宽度均相同，与各个负极极片卷绕层分别连接的负极极耳中的负极极耳段的数量沿所述卷绕方向增加。
采用宽度相同的正极极耳段，可降低正极极耳的加工难度，并使抚平后的正极极耳组更齐整，相应地还通过各个正极极片卷绕层连接的正极极耳段的数量的变化来实现对应的正极极耳的长度的变化。同样的，采用宽度相同的负极极耳段，可降低负极极耳的加工难度，并使抚平后的负极极耳组更齐整，相应地还通过各个负极极片卷绕层连接的负极极耳段的数量的变化来实现对应的负极极耳的长度的变化。
在一些实施例中，所述多个正极极耳和所述多个负极极耳满足以下至少一种：
各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最上游的端部位置均位于同一平面；
各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最下游的端部位置均位于同一平面；
各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最上游的端部位置均位于同一平面；
各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最下游的端部位置均位于同一平面。
使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端部位置对齐到同一平面，有利于向内抚平各层正极极耳时确保该侧端部的齐整，便于分隔正负极，并有利于后续的极耳焊接。同理，正极极耳的最下游端部对齐到同一平面、负极极耳的最上游端部对齐到同一平面以及负极极耳的最下游端部对齐到同一平面均可确保对应侧的端部的齐整，便于分隔正负极，并有利于后续的极耳焊接。
在一些实施例中，各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最上游的端部位置和位于最下游的端部位置均位于同一平面；和/或各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最上游的端部位置和位于最下游的端部位置均位于同一平面。
通过使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端 部位置和位于最下游的端部位置对齐到同一平面，可形成整体呈弓形的正极极耳组，这种弓形的正极极耳组在向内抚平后可以保持两端齐整，从而有效地与负极极耳组隔开，也方便自身与集流盘的焊接。同样的，通过使各个负极极片卷绕层分别连接的负极极耳在卷绕方向上位于最上游的端部位置和位于最下游的端部位置对齐到同一平面，可形成整体呈弓形的负极极耳组，这种弓形的负极极耳组在向内抚平后可以保持两端齐整，从而有效地与负极极耳组隔开，也方便自身与集流盘的焊接。
在一些实施例中，各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最上游的端部位置和各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最上游的端部位置均位于同一平面；
各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最下游的端部位置和各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最下游的端部位置均位于同一平面。
通过使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端部位置和各个负极极片卷绕层分别连接的负极极耳位于最下游的端部位置对齐到同一平面，以及使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最下游的端部位置和各个负极极片卷绕层分别连接的负极极耳位于最上游的端部位置对齐到同一平面，可形成整体上呈扇形且相互对称的正极极耳组和负极极耳组，这种结构种的极耳组一致性好，在焊接时更容易保持焊接效果的均匀性。
在一些实施例中，所述卷绕结构为绕卷绕轴线卷绕的圆柱形卷绕结构，所述多个正极极耳与所述多个负极极耳相对于所述卷绕轴线对称，或相对于通过所述卷绕轴线的平面对称。
为了提高正负极耳分别焊接集流盘时的一致性，可使多个正极极耳和多个负极极耳相对于卷绕轴线对称，也可使多个正极极耳和多个负极极耳相对于通过卷绕轴线的平面对称，这样通过抚平后的正极极耳组和负极极耳组在形态上的一致性来提高焊接效果的均匀性。
在一些实施例中，所述电极组件还包括：绝缘件，设置在所述主体部连接所述多个正极极耳和所述多个负极极耳一侧的端部，并位于所述多个正极极耳和所述多个负极极耳之间。
为了使位于主体部同侧的正极极耳和负极极耳更有效地分隔开，在多个正极极耳和多个负极极耳之间设置绝缘件来实现两者的有效分隔，降低发生短路的风险。
在一些实施例中，所述绝缘件包括绝缘塑胶块。
通过具有一定体积的绝缘塑胶块来隔离正极极耳和负极极耳，一方面可以有效地实现正极极耳和负极极耳之间的绝缘，避免两者发生短路，另一方面可以在主体部的端部形成一定的支撑作用，从而在电池端部受压时能够承受一定的挤压力，降低主体部受压带来的极片边缘脱碳的风险。
在一些实施例中，所述卷绕结构为绕卷绕轴线卷绕的圆柱形卷绕结构，所述圆柱形卷绕结构具有沿轴向贯通的第一中心孔，所述绝缘件具有与所述第一中心孔沿所述卷绕轴线连通的第二中心孔。
通过在绝缘件和圆柱形卷绕结构上分别设置第一中心孔和第二中心孔，可以实现电池单体中电解液的灌注。
在一些实施例中，所述第一中心孔和所述第二中心孔均为圆孔，且所述第一中心孔的直径D1大于等于所述第二中心孔的直径D2。
在采用直径不大于第一中心孔直径的第二中心孔时，极耳在被抚平后即便从绝缘件的上表面进入或穿过第二中心孔，也不容易进一步接触到第一中心孔径向外侧的极片，从而有效地降低发生短路的风险。
在一些实施例中，各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最上游的端部位置均位于第一平面，各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向上位于最下游的端部位置均位于第二平面，所述第一平面在周向上到所述第二平面的夹角范围θ1满足：θ1＝K1*(C/L)，且θ1≤180度；和/或
各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最上游的端部位置均位于第三平面，各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向上位于最下游的端部位置均位于第四平面，所述第三平面在周向上到所述第四平面的夹角范围θ2满足：θ2＝K2*(C/L)，且θ2≤180度；
其中，C为采用所述电极组件的电池的容量，L为所述负极极片的总长度，K1为第一比例参数，K2为第二比例参数。
前述夹角范围的取值不大于180度，如果超过180度，则容易在负极极耳或正极极耳抚平后接触到另一种极性的极耳，从而导致短路风险。极耳组对应的夹角范围、负极极片的总长度和电池容量均与流经极耳的电流密度存在关联，在电池容量一定时，负极极片总长度越长，对应到圆周周长的单位电荷量越少，因此在满足允许的电流密度的情况下，可采用夹角范围较小的极耳组；而在负极极片总长度一定时，电池容量 越大，对应到圆周周长的单位电荷量越多，为了避免流经极耳的电流密度过高，导致过流发热，则可采用夹角范围较大的极耳组。
在一些实施例中，所述电极组件的容量C的单位为安时，所述负极极片的总长度L的单位为毫米，所述第一比例参数K1大于等于
Figure PCTCN2022089733-appb-000001
所述第二比例参数K2大于等于
Figure PCTCN2022089733-appb-000002
通过限定第一比例参数K1和第二比例参数K2的适合取值范围，可使得极耳在充电时温度保持在允许范围内，避免过热而影响采用用电极组件的电池中化学物质的性能。
在一些实施例中，所述正极极片包括正极集流体和在所述正极集流体表面上覆盖的正极活性物质膜层，所述多个正极极耳连接在所述正极集流体沿所述卷绕方向延伸的第一侧边上，所述正极活性物质膜层从所述正极集流体表面连续延伸到所述多个正极极耳的部分表面，所述负极极片包括负极集流体、在所述负极集流体表面上覆盖的负极活性物质膜层和在所述负极集流体表面上覆盖的绝缘膜层，所述多个负极极耳连接在所述负极集流体沿所述卷绕方向延伸的第二侧边上，所述绝缘膜层位于所述负极活性物质膜层在第一方向上的前侧，且从所述负极集流体表面连续延伸到所述多个负极极耳的部分表面，所述第一方向为所述多个正极极耳相对于所述正极极片的延伸方向或所述多个负极极耳相对于所述负极极片的延伸方向，且所述第一方向与所述卷绕方向垂直。
通常来说，正极活性物质膜层的边缘部分更薄，而较薄的正极活性物质膜层可能造成极片间过大的间隙，从而不容易存留住电解液，造成局部电解液浸润效果差，容易发生析锂的问题。而采用模切等方式在正极极片上切出正极极耳时，通过切除设有正极活性物质膜层的正极极片侧边，可形成正极活性物质膜层从正极集流体表面连续延伸到正极极耳的部分表面的状态，相应地，这种正极极片邻近正极极耳一侧的侧边被覆盖的正极活性物质膜层的厚度与正极极片其他位置更加一致，从而更容易存留住电解液，获得更好的电解液浸润效果，降低析锂风险。
同样的，绝缘膜层的边缘部分更薄，而较薄的绝缘膜层可能造成极片间过大的间隙，从而不容易存留住电解液，造成局部电解液浸润效果差，容易发生析锂的问题。而采用模切等方式在负极极片上切出负极极耳时，通过切除设有绝缘膜层的负极极片侧边，可形成绝缘膜层从负极集流体表面连续延伸到负极极耳的部分表面的状态，相 应地，这种负极极片邻近负极极耳一侧的侧边被覆盖的绝缘膜层的厚度与负极极片其他位置更加一致，从而更容易存留住电解液，获得更好的电解液浸润效果，降低析锂风险。
在一些实施例中，在所述第一方向上，所述正极活性物质膜层在所述多个正极极耳的延伸部分的最前端均位于所述第一侧边的前侧。
对于采用模切方式形成正极极耳的制备方式来说，第一侧边相当于正极的模切边，而正极活性物质膜层在正极极耳上的延伸部分的最前端相当于正极的涂膜边。如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，则正极的涂膜边的高度大于正极的模切边，这样可以在模切时将与正极极耳之外且低于正极的涂膜边的一定高度的正极极片部分切除，从而切掉正极极片对应于正极活性物质膜层边缘的减薄部分的部分，这样可以降低该部分可能存在的电解液缺失问题，降低发生局部析锂的风险。
在一些实施例中，在所述第一方向上，所述第一侧边位于所述第二侧边的后侧。对于采用模切方式形成正极极耳和负极极耳的制备方式来说，第一侧边相当于正极的模切边，第二侧边相当于负极的模切边。
如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，则正极的模切边的高度小于负极的模切边的高度。这样当负极极耳被抚平时，如果发生极耳皱褶朝极片的方向插入，则负极极片会先与负极极片上的绝缘涂层先发生搭接，而不容易先与正极极片上的正极活性物质膜层搭接，从而降低短路风险。
在一些实施例中，在所述第一方向上，所述正极活性物质膜层在所述多个正极极耳的延伸部分的最前端位于所述绝缘膜层在所述多个负极极耳的延伸部分的最前端的后侧。
如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，则正极活性物质膜层在正极极耳上的涂膜边的高度小于绝缘层在负极极耳上的涂膜边的高度。这样当电极组件端部受压时，绝缘层会先于正极活性物质膜层受压，这样可以降低正极活性物质膜层在受压时发生脱碳，从而造成短路的风险。
在一些实施例中，所述多个正极极耳中的至少一个正极极耳在远离所述正极极片一侧的侧边具有至少一个第一缺口，所述至少一个第一缺口将所述正极极耳沿所述卷绕方向分隔为多个正极极耳段，所述至少一个第一缺口的根部在所述第一方向上位于所述隔膜的前侧；
所述多个负极极耳中的至少一个负极极耳在远离所述负极极片一侧的侧边具有 至少一个第二缺口，所述至少一个第二缺口将所述负极极耳沿所述卷绕方向分隔为多个负极极耳段，所述至少一个第二缺口的根部在所述第一方向上位于所述隔膜的前侧。
如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，则第一缺口的根部和第二缺口的根部的高度大于隔膜的高度。由于第一缺口的根部和第二缺口的根部通常为极耳段折弯抚平的位置，因此当将极耳段抚平后与集流盘进行焊接时，焊接时受热的极耳段可与隔膜保持一定距离，从而降低焊接时隔膜被烫伤的可能性，进而防止因隔膜被烫伤而导致短路。
在一些实施例中，所述电极组件还包括：
正极集流盘，位于所述多个正极极耳远离所述主体部的一侧，并与已抚平的所述多个正极极耳通过焊接方式固定连接；和
负极集流盘，位于所述多个负极极耳远离所述主体部的一侧，并与已抚平的所述多个负极极耳通过焊接方式固定连接；
其中，所述多个正极极耳在所述至少一个第一缺口的根部朝向所述主体部的端部中心折弯并抚平，所述多个负极极耳在所述至少一个第二缺口的根部朝向所述主体部的端部中心折弯并抚平，所述至少一个第一缺口的根部与所述隔膜在所述第一方向上的第一距离d1大于等于所述正极集流盘的厚度t1的1.5倍，所述至少一个第二缺口的根部与所述隔膜在所述第一方向上的第二距离d2大于等于所述负极集流盘的厚度t2的1.5倍。
由于集流盘的厚度与焊接时的热量相关，越厚的集流盘焊接时热量更高，相应地，使第一缺口的根部与隔膜在第一方向上的第一距离大于正极集流盘的厚度的1.5倍，以及使第二缺口的根部与隔膜在第一方向上的第二距离均大于负极集流盘的厚度的1.5倍，可以有效地降低焊接集流盘时隔膜被烫伤的可能性，进而防止因隔膜被烫伤而导致短路。
在一些实施例中，相邻正极极耳段之间第一缺口的根部和相邻负极极耳段之间第二缺口的根部位于与所述第一方向垂直的同一平面。
如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，通过将第一缺口的根部和第二缺口的根部设置在同一高度，可使得正极极耳和负极极耳在抚平后焊接时能够尽量处于同一平面，从而确保焊接不容易出现虚焊现象。
在一些实施例中，所述电极组件还包括：
绝缘件，设置在所述主体部连接所述多个正极极耳和所述多个负极极耳一侧的端 部，并位于所述多个正极极耳和所述多个负极极耳之间，
其中，在所述第一方向上，所述至少一个第一缺口的根部与所述第二侧边的距离为第三距离d3，所述至少一个第二缺口的根部与所述第二侧边的距离为第四距离d4，所述绝缘件位于所述第二侧边的前侧，且所述绝缘件沿所述第一方向的最前端与所述第二侧边的距离为第五距离d5，所述正极活性物质膜层在所述多个正极极耳的延伸部分的最前端与所述第二侧边的距离为第六距离d6，所述第三距离d3、所述第四距离d4、所述第五距离d5和所述第六距离d6满足：d5<d6，d3<d5，d4<d5。
在第一方向上，第一缺口的根部和第二缺口的根部相比于绝缘件更靠前，这样在焊接集流盘时，集流盘会先与抚平的极耳接触并焊接，从而有效地避免虚焊现象。另外，绝缘件在第一方向上的最前端比正极活性物质膜层在正极极耳的最前端更靠前，这样在电极组件受压时，绝缘件会先于正极活性物质膜层受压，从而降低正极活性物质膜层在受压时发生脱碳，从而造成短路的风险。
在本公开的一个方面，提供一种电池单体，包括前述的电极组件。采用前述的电极组件的电池单体具有更好的性能。
在本公开的一个方面，提供一种电池，包括前述的电池单体。采用前述的电池单体的电池具有更好的性能。
在本公开的一个方面，提供一种用电装置，包括前述的电池。采用前述的电池的用电装置具有更好的性能。
在本公开的一个方面，提供一种电极组件的制造方法，包括：
提供隔膜、连接有正极全极耳的正极极片和连接有负极全极耳的负极极片；
将所述正极全极耳模切成沿所述正极极片的长度方向间隔排布的多个正极极耳，以及将所述负极全极耳模切成沿所述负极极片的长度方向间隔排布的多个负极极耳；
将所述正极极片、所述隔膜和所述负极极片卷绕成所述电极组件的主体部，并使所述多个正极极耳和所述多个负极极耳位于所述主体部在与所述主体部的卷绕方向垂直的方向上的同一侧端部；
将所述多个正极极耳和所述多个负极极耳折弯抚平；
其中，在模切所述正极全极耳和所述负极全极耳时，使与所述主体部的各个正极极片卷绕层分别连接的正极极耳在所述卷绕方向的长度沿所述卷绕方向增加，并使与所述主体部的各个负极极片卷绕层分别连接的负极极耳在所述卷绕方向的长度沿所述卷绕方向增加。
通过模切工艺将正极极片上形成的多个正极极耳和负极极片上形成的多个负极极耳设置在卷绕结构的同侧，这样正极极耳对应的集流盘和负极极耳对应的集流盘可分别汇集电流从同侧输出，相比于相关技术中在卷绕结构两端伸出极耳的结构，本实施例可以缩短通过极片到极柱的电子路径，使极耳无需经壳体引导电流，省去了壳体电阻对电池内阻的不利影响和壳体发热对电池内部散热的不利影响，从而降低电池内阻，改善电池散热，提升电池功率和快充能力。
通过使各层极片卷绕层所连接的正极极耳和负极极耳的长度沿卷绕方向增加，可使得极片卷绕后的各个正极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，以及使极片卷绕后的各个负极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，从而分别形成更齐整的正极极耳组和负极极耳组，便于分隔正负极，并有利于后续的极耳焊接，并且相互隔开的正极极耳以及相互隔开的负极极耳在弯折抚平时不容易产生皱褶，从而降低极耳破碎或皱褶插入极片带来短路的风险。
在一些实施例中，所述制造方法还包括：
在所述多个正极极耳和所述多个负极极耳之间固定绝缘件，以使所述多个正极极耳交叠形成的极耳组与所述多个负极极耳交叠形成的极耳组通过所述绝缘件隔离。
通过在位于主体部同侧的多个正极极耳和多个负极极耳之间设置绝缘件，可实现两者之间的有效分隔，进一步降低发生短路的风险。
在一些实施例中，所述制造方法还包括：
将正极集流盘焊接在已抚平的所述多个正极极耳上，并将负极集流盘焊接在已抚平的所述多个负极极耳上。
对已抚平的多个正极极耳和已抚平的多个负极极耳分别焊接正极集流盘和负极集流盘，可获得主体部同侧具有正极集流盘和负极集流盘的电极组件结构。
在一些实施例中，在模切出所述多个正极极耳的过程中，将所述多个正极极耳中的至少一个正极极耳远离所述正极极片一侧的侧边模切出至少一个第一缺口，以通过所述至少一个第一缺口将所述正极极耳沿所述卷绕方向分隔为多个正极极耳段；和/或
在模切出所述多个负极极耳的过程中，将所述多个负极极耳中的至少一个负极极耳远离所述负极极片一侧的侧边模切出至少一个第二缺口，以通过所述至少一个第二缺口将所述负极极耳沿所述卷绕方向分隔为多个负极极耳段。
通过将正极极耳的侧边模切出第一缺口来获得分隔的多个正极极耳段可以使正 极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。同样的，通过将负极极耳的侧边模切出第二缺口来获得分隔的多个负极极耳段可以使负极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
附图说明
为了更清楚地说明本公开实施例的技术方案，下面将对本公开实施例中所需要使用的附图作简单地介绍，显而易见地，下面所描述的附图仅仅是本公开的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
参照附图，根据下面的详细描述，可以更加清楚地理解本公开，其中：
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2是根据本公开电池的一些实施例的结构示意图；
图3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4是根据本公开电极组件的一些实施例中正极极片的展开示意图；
图5是根据本公开电极组件的一些实施例中负极极片的展开示意图；
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和图8分别是图6实施例在俯视角度下设有绝缘件的端部示意图和去掉绝缘件的端部示意图；
图9是根据本公开电极组件的另一些实施例的结构示意图；
图10是图9实施例在俯视角度下设去掉绝缘件的端部示意图；
图11和图12分别是图6实施例和图9实施例中电极极耳和绝缘件在主体部的端部的覆盖范围的示意图；
图13是根据本公开电极组件的一些实施例中正极极片、负极极片和隔膜的设置示意图；
图14根据本公开电极组件的又一些实施例的结构示意图；
图15是根据本公开电极组件的一些实施例中正极极片、负极极片、隔膜和绝缘件的设置示意图；
图16是根据本公开电极组件的制造方法的一些实施例的流程示意图。
应当明白，附图中所示出的各个部分的尺寸并不是按照实际的比例关系绘制的。 此外，相同或类似的参考标号表示相同或类似的构件。
附图标记说明：
10：电池单体；10A：正极极片；10B：负极极片；10C：隔膜；100：卷绕结构；11：正极集流体；12正极活性物质膜层；13：负极集流体；14：负极活性物质膜层；15：绝缘膜层；16：第一侧边；17：第二侧边；18：第三侧边；121：正极涂膜边；151：绝缘膜层涂膜边；153：负极涂膜边；
20：正极极耳；21：正极极耳段；22：第一缺口；23：第一缺口的根部；
30：负极极耳；31：负极极耳段；32：第二缺口；33：第二缺口的根部；
40：绝缘件；41：第二中心孔；42：绝缘件的最前端；
51：正极集流盘；52：负极集流盘；53：第一电极端子；54：第二电极端子；
60：电池；61：箱体；62：封盖；
70：车辆。
具体实施方式
下面结合附图和实施例对本公开的实施方式作进一步详细描述。以下实施例的详细描述和附图用于示例性地说明本公开的原理，但不能用来限制本公开的范围，即本公开不限于所描述的实施例。
在本公开的描述中，需要说明的是，除非另有说明，“多个”的含义是两个以上；术语“上”、“下”、“左”、“右”、“内”、“外”等指示的方位或位置关系仅是为了便于描述本公开和简化描述，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公开的限制。此外，术语“第一”、“第二”、“第三”等仅用于描述目的，而不能理解为指示或暗示相对重要性。“垂直”并不是严格意义上的垂直，而是在误差允许范围之内。“平行”并不是严格意义上的平行，而是在误差允许范围之内。
下述描述中出现的方位词均为图中示出的方向，并不是对本公开的具体结构进行限定。在本公开的描述中，还需要说明的是，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是直接相连，也可以通过中间媒介间接相连。对于本领域的普通技术人员而言，可视具体情况理解上述术语在本公开中的具体含义。
下面结合附图，对本发明的一些实施方式作详细说明。在不冲突的情况下，下述 的实施例中的特征可以相互组合。
在一些相关技术中，圆柱形电池单体中的电极组件具有在卷绕结构两端伸出的极耳，其中一端伸出的极耳与壳体电连接，并通过壳体导向与另一端伸出的极耳的同一侧。经研究发现，这种圆柱形电池单体会因壳体电阻耳导致整个电池的内阻增加，而壳体过流会产生热量，影响电池内的热量散出，从而影响电池的性能。
有鉴于此，本公开实施例提供一种电池单体、电池、用电设备、电极组件及其制造方法，能够提升电池的性能。
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。电池可包括壳体和电池模组，壳体用于为电池模组提供容纳空间，电池模组安装在壳体内。壳体可采用金属材质。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70的内部设置有电池60，电池60设置于车辆的底部或头部或尾部。电池60为车辆供电，例如，电池60作为车辆的操作电源。该电池60可作为新能源汽车、船舶、智能电器柜等装置的电源。电池60也可作为电源供给部件，给装置的各种电器元件提供所需要的电能。
图2是根据本公开电池的一些实施例的结构示意图。参考图2，在一些实施例中， 电池60包括箱体61、封盖62以及设置于箱体61中的一个或者多个电池单体10。为了便于观察箱体61内的多个电池单体10，图2只显示了一部分封盖62。各个电池单体10之间电连接，比如串联、并联或者混联，以实现所需要的电池60的电性能参数。多个电池单体10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10。
在一些实施例中，电池60的各电池单体10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10。根据需要，还可以在电池60的高度方向，也可设置一层或者多层电池单体10。
在一些实施例中，多个电池单体10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61内。在另一些实施例中，所有电池单体10直接串联或并联或混联在一起，再将所有电池单体10构成的整体容纳于箱体内。
电池单体10可包括壳体、端盖和电极组件。壳体具有空腔，用于容纳所述电极组件，且所述壳体的端部可被构造为敞口的，用于设置端盖组件。电极组件则被装在壳体的空腔中。电池单体10除了包括电极组件、端盖和壳体，还包括电解液。
图3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4是根据本公开电极组件的一些实施例中正极极片的展开示意图。图5是根据本公开电极组件的一些实施例中负极极片的展开示意图。图6是根据本公开电极组件的一些实施例的结构示意图。
参考图3，在一些实施例中，电极组件包括：主体部100、多个正极极耳20和多个负极极耳30。主体部100包括：正极极片10A、负极极片10B和设于所述正极极片10A和所述负极极片10B之间的隔膜10C。所述正极极片10A、所述隔膜10C和所述负极极片10B沿卷绕方向r卷绕并形成卷绕结构，例如形成图3中沿卷绕机构的径向形成的负极极片10B、隔膜10C、正极极片10A、隔膜10C……的层叠结构。卷绕结构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。
参考图4和图6，多个正极极耳20分别与所述卷绕结构中的至少两个正极极片卷绕层连接，并沿所述卷绕方向r间隔排布。参考图5和图6，多个负极极耳30分别与所述卷绕结构中的至少两个负极极片卷绕层连接，并沿所述卷绕方向r间隔排布。所 述多个正极极耳20和所述多个负极极耳30位于所述主体部100在与所述卷绕方向r垂直的方向上的同一侧端部。
将正极极片连接的多个正极极耳和负极极片连接的多个负极极耳设置在卷绕结构的同侧，这样正极极片的集流体和负极极片的集流体可分别汇集电流从同侧输出，相比于相关技术中在卷绕结构两端伸出极耳的结构，本实施例可以缩短通过极片到极柱的电子路径，使极耳无需经壳体引导电流，省去了壳体电阻对电池内阻的不利影响和壳体发热对电池内部散热的不利影响，从而降低电池内阻，改善电池散热，提升电池功率和快充能力。
参考图4-图6，与各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r的长度b1沿所述卷绕方向r增加，与各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r的长度b2沿所述卷绕方向r增加。
通过使各层极片卷绕层所连接的正极极耳和负极极耳的长度沿卷绕方向增加，可使得极片卷绕后的各个正极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，以及使极片卷绕后的各个负极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，从而分别形成更齐整的正极极耳组和负极极耳组，便于分隔正负极，并有利于后续的极耳焊接，并且相互隔开的正极极耳以及相互隔开的负极极耳在弯折抚平时不容易产生皱褶，从而降低极耳破碎或皱褶插入极片带来短路的风险。
图7和图8分别是图6实施例在俯视角度下设有绝缘件的端部示意图和去掉绝缘件的端部示意图。图9是根据本公开电极组件的另一些实施例的结构示意图。图10是图9实施例在俯视角度下设去掉绝缘件的端部示意图。图11和图12分别是图6实施例和图9实施例中电极极耳和绝缘件在主体部的端部的覆盖范围的示意图。
参考图6和图9，在一些实施例中，所述卷绕结构为绕卷绕轴线ax卷绕的圆柱形卷绕结构。相比于相关技术中圆柱电池所采用的圆柱形卷绕结构在两端分别伸出正极极耳和负极极耳，本实施例中正极极耳和负极极耳位于圆柱形卷绕结构的同侧，可以有效地降低电池内阻，改善电池散热，而且随着圆柱形卷绕结构从外到内的极片卷绕层的周长逐渐减小，各层对应的极耳长度也随之减小，这样各层极耳在向圆心方向抚平后会更加齐整，便于分隔正负极，并有利于后续的极耳焊接。
另外，通过各个极片卷绕层分别连接的极耳之间的间隔可以使卷绕后的正极极耳和负极极耳能够实现分区，降低抚平后极性相反的两个极片组未有效分隔而导致短路 的风险。
在图6-图12中，所述多个正极极耳20在所述主体部100的端部相对于所述卷绕轴线ax的角度范围与所述多个负极极耳30在所述主体部100的端部相对于所述卷绕轴线ax的角度范围不重合。通过使圆柱形卷绕结构同侧的多个正极极耳和多个负极极耳的角度范围不相重合，可有效地降低抚平后极性相反的两个极片组未有效分隔而导致短路的风险。
为了使位于主体部同侧的正极极耳和负极极耳更有效地分隔开，参考图6、图7、图11和图12，在一些实施例中，电极组件还包括：绝缘件40。绝缘件40设置在所述主体部100连接所述多个正极极耳20和所述多个负极极耳30一侧的端部，并位于所述多个正极极耳20和所述多个负极极耳30之间。这样通过在多个正极极耳和多个负极极耳之间设置绝缘件来实现两者的有效分隔，降低发生短路的风险。
在一些实施例中，所述绝缘件40包括绝缘塑胶块。绝缘塑胶孔的形状和大小可根据正极极耳和负极极耳的覆盖范围确定。通过具有一定体积的绝缘塑胶块来隔离正极极耳和负极极耳，一方面可以有效地实现正极极耳和负极极耳之间的绝缘，避免两者发生短路，另一方面可以在主体部的端部形成一定的支撑作用，从而在电池端部受压时能够承受一定的挤压力，降低主体部受压带来的极片边缘脱碳的风险。
对于绕卷绕轴线ax卷绕的圆柱形卷绕结构来说，参考图7和图8，在一些实施例中，所述圆柱形卷绕结构具有沿轴向贯通的第一中心孔110，所述绝缘件40具有与所述第一中心孔110沿所述卷绕轴线ax连通的第二中心孔41。通过在绝缘件和圆柱形卷绕结构上分别设置第一中心孔和第二中心孔，可以实现电池单体中电解液的灌注。
在一些实施例中，所述第一中心孔110和所述第二中心孔41均为圆孔，且所述第一中心孔110的直径D1大于等于所述第二中心孔41的直径D2。在采用直径不大于第一中心孔直径的第二中心孔时，极耳在被抚平后即便从绝缘件的上表面进入或穿过第二中心孔，也不容易进一步接触到第一中心孔径向外侧的极片，从而有效地降低发生短路的风险。
参考图11和图12，在一些实施例中，所述多个正极极耳20和所述多个负极极耳30满足以下至少一种：各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最上游的端部位置均位于同一平面(例如第一平面S1)；各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最下游的端部位置均位于同一平面(例如第二平面S2)；各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方 向r上位于最上游的端部位置均位于同一平面(例如第三平面S3)；各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最下游的端部位置均位于同一平面(例如第四平面S4)。
本实施例使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端部位置对齐到同一平面，有利于向内抚平各层正极极耳时确保该侧端部的齐整，便于分隔正负极，并有利于后续的极耳焊接。同理，正极极耳的最下游端部对齐到同一平面、负极极耳的最上游端部对齐到同一平面以及负极极耳的最下游端部对齐到同一平面均可确保对应侧的端部的齐整，便于分隔正负极，并有利于后续的极耳焊接。
参考图11，在一些实施例中，各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最上游的端部位置和位于最下游的端部位置均位于同一平面，例如第一平面S1和第二平面S2共面。通过使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端部位置和位于最下游的端部位置对齐到同一平面，可形成整体呈弓形的正极极耳组，这种弓形的正极极耳组在向内抚平后可以保持两端齐整，从而有效地与负极极耳组隔开，也方便自身与集流盘的焊接。
同样的，各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最上游的端部位置和位于最下游的端部位置均位于同一平面，例如第三平面S3和第四平面S4共面。通过使各个负极极片卷绕层分别连接的负极极耳在卷绕方向上位于最上游的端部位置和位于最下游的端部位置对齐到同一平面，可形成整体呈弓形的负极极耳组，这种弓形的负极极耳组在向内抚平后可以保持两端齐整，从而有效地与负极极耳组隔开，也方便自身与集流盘的焊接。
参考图12，在一些实施例中，各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最上游的端部位置和各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最上游的端部位置均位于同一平面，例如第一平面S1和第三平台S3共面。各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最下游的端部位置和各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最下游的端部位置均位于同一平面，例如第二平面S2和第四平台S4共面。
本实施例通过使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最上游的端部位置和各个负极极片卷绕层分别连接的负极极耳位于最下游的端部位置对齐到同一平面，以及使各个正极极片卷绕层分别连接的正极极耳在卷绕方向上位于最下游的端部位置和各个负极极片卷绕层分别连接的负极极耳位于最上游的端部位 置对齐到同一平面，可形成整体上呈扇形且相互对称的正极极耳组和负极极耳组，这种结构种的极耳组一致性好，在焊接时更容易保持焊接效果的均匀性。
对于绕卷绕轴线ax卷绕的圆柱形卷绕结构来说，为了提高正负极耳分别焊接集流盘时的一致性，参考图6-图12，在一些实施例中，所述多个正极极耳20与所述多个负极极耳30相对于所述卷绕轴线ax对称，或相对于通过所述卷绕轴线ax的平面对称。这样通过抚平后的正极极耳组和负极极耳组在形态上的一致性来提高焊接效果的均匀性。
参考图11和图12，在一些实施例中，各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最上游的端部位置均位于第一平面S1，各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r上位于最下游的端部位置均位于第二平面S2，所述第一平面S1在周向上到所述第二平面S2的夹角范围θ1可满足：θ1＝K1*(C/L)，且θ1≤180度。C为采用所述电极组件的电池的容量，L为所述负极极片10B的总长度，K1为第一比例参数。
各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最上游的端部位置均位于第三平面S3，各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r上位于最下游的端部位置均位于第四平面S4，所述第三平面S3在周向上到所述第四平面S4的夹角范围θ2可满足：θ2＝K2*(C/L)，且θ2≤180度。C为采用所述电极组件的电池的容量，L为所述负极极片10B的总长度，K2为第二比例参数。
前述夹角范围的取值不大于180度，如果超过180度，则容易在负极极耳或正极极耳抚平后接触到另一种极性的极耳，从而导致短路风险。极耳组对应的夹角范围、负极极片的总长度L和电池容量C均与流经极耳的电流密度存在关联，在电池容量C一定时，负极极片总长度L越长，对应到圆周周长的单位电荷量越少，因此在满足允许的电流密度的情况下，可采用夹角范围较小的极耳组；而在负极极片总长度L一定时，电池容量C越大，对应到圆周周长的单位电荷量越多，为了避免流经极耳的电流密度过高，导致过流发热，则可采用夹角范围较大的极耳组。
在一些实施例中，所述电极组件的容量C的单位为安时，所述负极极片10B的总长度L的单位为毫米，所述第一比例参数K1大于等于
Figure PCTCN2022089733-appb-000003
所述第二比例参数K2大于等于
Figure PCTCN2022089733-appb-000004
通过限定第一比例参数K1和第二比例参数K2的适合取值范围，可使得极耳在充电时温度保持在允许范围内，避免过热而影响采用用电极 组件的电池中化学物质的性能。
参考前述实施例，当电极组件用于锂二次电池时，由于锂盐、溶剂、正极活性材料和负极活性物质在高温情况下会出现加速的副反应甚至分解，因此通常在电极组件正常使用时应控制在低于80℃，优选的，在60℃以下。在一个实验例中，电池组件的容量C为45安时，负极极片的总长L为4827mm，按照
Figure PCTCN2022089733-appb-000005
Figure PCTCN2022089733-appb-000006
进行计算，θ1和θ2均约等于112度。故实际夹角范围θ1和θ2采用大于112度的120度时，对应的K1和K2大于
Figure PCTCN2022089733-appb-000007
而测量快充时的极耳根部温度为50℃，满足此种电池极耳温度低于60℃和80℃的要求。
参考前述实施例，在另一个实验例中，电池组件的容量C为32.5安时，负极极片的总长L为4585mm，按照
Figure PCTCN2022089733-appb-000008
进行计算，θ1和θ2均约等于85度。故实际夹角范围θ1和θ2采用大于85度的90度时，对应的K1和K2大于
Figure PCTCN2022089733-appb-000009
而测量快充时的极耳根部温度为52℃，满足此种电池极耳温度低于60℃和80℃的要求。
参考前述实施例，在一个对比实验例中，电池组件的容量C为30安时，负极极片的总长L为4585mm，按照
Figure PCTCN2022089733-appb-000010
进行计算，θ1和θ2均约等于78度。故实际夹角范围θ1和θ2采用小于78度的30度时，对应的K1和K2小于
Figure PCTCN2022089733-appb-000011
而测量快充时的极耳根部温度为80℃，不满足此种电池极耳温度低于60℃和80℃的要求。
通过上述实验例和对比实验例可知，通过选取合适的夹角范围θ1和θ2，可降低快充时的极耳温度，避免因极耳温度过高影响电池内的化学物质性能，降低电池寿命，导致电池失效。
图13是根据本公开电极组件的一些实施例中正极极片、负极极片和隔膜的设置示意图。参考图4和图13，在一些实施例中，所述多个正极极耳20中的至少一个正极极耳20在远离所述正极极片10A一侧的侧边具有至少一个第一缺口22，所述至少一个第一缺口22将所述正极极耳20沿所述卷绕方向r分隔为多个正极极耳段21。
通过将正极极耳的侧边设置第一缺口来获得分隔的多个正极极耳段可以使正极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
所述多个负极极耳30中的至少一个负极极耳30在远离所述负极极片10B一侧的侧边可具有至少一个第二缺口32，所述至少一个第二缺口32将所述负极极耳30沿所述卷绕方向r分隔为多个负极极耳段31。通过将负极极耳的侧边设置第二缺口来获得分隔的多个负极极耳段可以使负极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
在另一些实施例中，正极极耳可不具有第一缺口，在卷绕方向r上连续而不划分为多个正极极耳段；负极极耳也可不具有第二缺口，在卷绕方向r上连续而不划分为多个负极极耳段。
在一些实施例中，各个正极极耳段21在所述卷绕方向r上的宽度均相同，与各个正极极片卷绕层分别连接的正极极耳20中的正极极耳段21的数量可沿所述卷绕方向r增加。例如对应于靠内的正极极片卷绕层的正极极耳段21的数量少于对应于靠外的正极极片卷绕层的正极极耳段21的数量，这种数量的变化可以是连续的，也可以是按阶段变化的。采用宽度相同的正极极耳段21，可降低正极极耳的加工难度，并使抚平后的正极极耳组更齐整，相应地还通过各个正极极片卷绕层连接的正极极耳段21的数量的变化来实现对应的正极极耳的长度b1的变化。
各个负极极耳段31在所述卷绕方向r上的宽度均相同，与各个负极极片卷绕层分别连接的负极极耳30中的负极极耳段31的数量沿所述卷绕方向r增加。例如对应于靠内的负极极片卷绕层的负极极耳段31的数量少于对应于靠外的负极极片卷绕层的负极极耳段31的数量，这种数量的变化可以是连续的，也可以是按阶段变化的。采用宽度相同的负极极耳段31，可降低负极极耳的加工难度，并使抚平后的负极极耳组更齐整，相应地还通过各个负极极片卷绕层连接的负极极耳段31的数量的变化来实现对应的负极极耳的长度b2的变化。
参考图13，在一些实施例中，所述正极极片10A包括正极集流体11和在所述正极集流体11表面上覆盖的正极活性物质膜层12。所述多个正极极耳20连接在所述正极集流体11沿所述卷绕方向r延伸的第一侧边16上。所述正极活性物质膜层12从所述正极集流体11表面连续延伸到所述多个正极极耳20的部分表面。
以锂离子电池为例，正极集流体11的材料可以为铝，正极活性物质膜层12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，多个正极极耳20可以焊接在正极集流体11的第一侧边。多个正极极耳20也可以通过对正极集流体11的模切来形成。
通常来说，正极活性物质膜层的边缘部分更薄，而较薄的正极活性物质膜层可能造成极片间过大的间隙，从而不容易存留住电解液，造成局部电解液浸润效果差，容易发生析锂的问题。而采用模切等方式在正极极片上切出正极极耳时，通过切除设有正极活性物质膜层的正极极片侧边，可形成正极活性物质膜层从正极集流体表面连续延伸到正极极耳的部分表面的状态，相应地，这种正极极片邻近正极极耳一侧的侧边被覆盖的正极活性物质膜层的厚度与正极极片其他位置更加一致，从而更容易存留住电解液，获得更好的电解液浸润效果，降低析锂风险。
所述负极极片10B包括负极集流体13、在所述负极集流体13表面上覆盖的负极活性物质膜层14和在所述负极集流体13表面上覆盖的绝缘膜层15。所述多个负极极耳30连接在所述负极集流体13沿所述卷绕方向r延伸的第二侧边17上。所述绝缘膜层15(例如陶瓷绝缘层等)位于所述负极活性物质膜层14在第一方向a上的前侧，且从所述负极集流体13表面连续延伸到所述多个负极极耳30的部分表面。绝缘层15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。
负极集流体13的材料可以为铜，负极活性物质膜层14可以为碳或硅等。在一些实施例中，多个负极极耳30可以焊接在负极集流体13的第二侧边17。多个负极极耳30也可以通过对负极集流体13的模切来形成。
参见图13，第一方向a为所述多个正极极耳20相对于所述正极极片10A的延伸方向或所述多个负极极耳30相对于所述负极极片10B的延伸方向，且所述第一方向与所述卷绕方向r垂直。
类似于正极极片上的正极活性物质膜层在边缘部分较薄的结构，绝缘膜层的边缘部分也较薄，而较薄的绝缘膜层可能造成极片间过大的间隙，从而不容易存留住电解液，造成局部电解液浸润效果差，容易发生析锂的问题。而采用模切等方式在负极极片上切出负极极耳时，通过切除设有绝缘膜层的负极极片侧边，可形成绝缘膜层从负极集流体表面连续延伸到负极极耳的部分表面的状态，相应地，这种负极极片邻近负极极耳一侧的侧边被覆盖的绝缘膜层的厚度与负极极片其他位置更加一致，从而更容易存留住电解液，获得更好的电解液浸润效果，降低析锂风险。
在图13中，在所述第一方向a上，所述正极活性物质膜层12在所述多个正极极耳20的延伸部分的最前端均位于所述第一侧边16的前侧。对于采用模切方式形成正极极耳的制备方式来说，第一侧边16相当于正极极片10A的模切边，而正极活性物质膜层12在正极极耳20上的延伸部分的最前端定义为正极涂膜边121。
如果以第一侧边16在第一方向a的反方向上的对侧侧边作为基准，则正极涂膜边121的高度大于正极极片10A的模切边，这样可以在模切时将与正极极耳之外且低于正极涂膜边121一定高度的正极极片部分切除，从而切掉正极极片对应于正极活性物质膜层边缘的减薄部分的部分，这样可以降低该部分可能存在的电解液缺失问题，降低发生局部析锂的风险。
在图13中，在所述第一方向a上，所述第一侧边16位于所述第二侧边17的后侧。对于采用模切方式形成正极极耳和负极极耳的制备方式来说，第一侧边16相当于正极极片10A的模切边，第二侧边17相当于负极极片10B的模切边。如果以第一侧边16在第一方向a的反方向上的对侧侧边作为基准，则正极极片的模切边的高度小于负极极片的模切边的高度。这样当负极极耳被抚平时，如果发生极耳皱褶朝极片的方向插入，则负极极片会先与负极极片上的绝缘涂层先发生搭接，而不容易先与正极极片上的正极活性物质膜层搭接，从而降低短路风险。
在图13中，在所述第一方向a上，所述正极活性物质膜层12在所述多个正极极耳20的延伸部分的最前端位于所述绝缘膜层15在所述多个负极极耳30的延伸部分的最前端的后侧。正极活性物质膜层12在正极极耳20上的延伸部分的最前端定义为正极涂膜边121，绝缘膜层15在负极极耳30上的延伸部分的最前端定义为绝缘膜层涂膜边151。
如果以第一侧边16在第一方向a的反方向上的对侧侧边作为基准，则正极涂膜边121的高度小于绝缘膜层涂膜边151的高度。这样当电极组件端部受压时，绝缘层会先于正极活性物质膜层受压，这样可以降低正极活性物质膜层在受压时发生脱碳，从而造成短路的风险。
在一些实施例中，所述多个正极极耳20中的至少一个正极极耳20在远离所述正极极片10A一侧的侧边具有至少一个第一缺口22，所述至少一个第一缺口22将所述正极极耳20沿所述卷绕方向r分隔为多个正极极耳段21，所述至少一个第一缺口22的根部23在所述第一方向上位于所述隔膜10C的前侧。所述多个负极极耳30中的至少一个负极极耳30在远离所述负极极片10B一侧的侧边具有至少一个第二缺口32，所述至少一个第二缺口32将所述负极极耳30沿所述卷绕方向r分隔为多个负极极耳段31，所述至少一个第二缺口32的根部33在所述第一方向上位于所述隔膜10C的前侧。
如果以第一侧边在第一方向的反方向上的对侧侧边作为基准，则第一缺口的根部 和第二缺口的根部的高度大于隔膜的高度。由于第一缺口的根部和第二缺口的根部通常为极耳段折弯抚平的位置，因此当将极耳段抚平后与集流盘进行焊接时，焊接时受热的极耳段可与隔膜保持一定距离，从而降低焊接时隔膜被烫伤的可能性，进而防止因隔膜被烫伤而导致短路。
图14根据本公开电极组件的又一些实施例的结构示意图。参考图14，在一些实施例中，电极组件还包括：正极集流盘51和负极集流盘52。正极集流盘51位于所述多个正极极耳20远离所述主体部100的一侧，并与已抚平的所述多个正极极耳20通过焊接方式固定连接。负极集流盘52位于所述多个负极极耳30远离所述主体部100的一侧，并与已抚平的所述多个负极极耳30通过焊接方式固定连接。在图14中，正极集流盘51可以与第一电极端子53和第二电极端子54中的任一个电连接，而负极集流盘52可以与第一电极端子53和第二电极端子54中的另一个电连接。
参考13和图14，多个正极极耳20在所述至少一个第一缺口22的根部23朝向所述主体部100的端部中心折弯并抚平，所述多个负极极耳30在所述至少一个第二缺口32的根部33朝向所述主体部100的端部中心折弯并抚平。
所述至少一个第一缺口22的根部23与所述隔膜10C(即与隔膜10C的第三侧边18)在所述第一方向a上的第一距离d1大于等于所述正极集流盘51的厚度t1的1.5倍，即d1≥1.5*t1。所述至少一个第二缺口32的根部33与所述隔膜10C(即与隔膜10C的第三侧边18)在所述第一方向上a的第二距离d2大于等于所述负极集流盘52的厚度t2的1.5倍，即d2≥1.5*t2。
由于集流盘的厚度与焊接时的热量相关，越厚的集流盘焊接时热量更高，相应地，使第一缺口的根部与隔膜在第一方向上的第一距离大于正极集流盘的厚度的1.5倍，以及使第二缺口的根部与隔膜在第一方向上的第二距离大于负极集流盘的厚度的1.5倍，可以有效地降低焊接集流盘时隔膜被烫伤的可能性，进而防止因隔膜被烫伤而导致短路。
在一些实施例中，相邻正极极耳段21之间第一缺口22的根部和相邻负极极耳段31之间第二缺口32的根部位于与所述第一方向垂直的同一平面。如果以第一侧边16在第一方向a的反方向上的对侧侧边作为基准，通过将第一缺口22的根部23和第二缺口32的根部33设置在同一高度，可使得正极极耳和负极极耳在抚平后焊接时能够尽量处于同一平面，从而确保焊接不容易出现虚焊现象。
图15是根据本公开电极组件的一些实施例中正极极片、负极极片、隔膜和绝缘件 的设置示意图。图15中示意性地绘制了绝缘件40相对于展开的正极极片10A、负极极片10B和隔膜10C的设置位置，可以看到绝缘件40位于正极极耳20与负极极耳30之间，且在所述第一方向a上，所述至少一个第一缺口22的根部23与所述第二侧边17的距离为第三距离d3，所述至少一个第二缺口32的根部33与所述第二侧边17的距离为第四距离d4。
在第一方向a上，所述绝缘件40位于所述第二侧边17的前侧，且所述绝缘件40的最前端42与所述第二侧边17的距离为第五距离d5。所述正极活性物质膜层12在所述多个正极极耳20的延伸部分的最前端(即正极涂膜边121)与所述第二侧边17的距离为第六距离d6。所述第三距离d3、所述第四距离d4、所述第五距离d5和所述第六距离d6满足：d5<d6，d3<d5，d4<d5。
在第一方向上，第一缺口的根部和第二缺口的根部相比于绝缘件更靠前，这样在焊接集流盘时，集流盘会先与抚平的极耳接触并焊接，从而有效地避免虚焊现象。另外，绝缘件在第一方向上的最前端比正极活性物质膜层在正极极耳的最前端更靠前，这样在电极组件受压时，绝缘件会先于正极活性物质膜层受压，从而降低正极活性物质膜层在受压时发生脱碳，从而造成短路的风险。
图16是根据本公开电极组件的制造方法的一些实施例的流程示意图。前述电极组件的实施例可通过图16所示的制造方法获得。参考图16，在一些实施例中，电极组件的制造方法包括：步骤S1、步骤S2、步骤S3和步骤S4。在步骤S1中，提供隔膜10C、连接有正极全极耳的正极极片10A和连接有负极全极耳的负极极片10B。正极极片10A和负极极片10B可以采用制浆、涂敷、轧制和分切等工艺获得。
在步骤S2中，将所述正极全极耳模切成沿所述正极极片10A的长度方向间隔排布的多个正极极耳20，以及将所述负极全极耳模切成沿所述负极极片10B的长度方向间隔排布的多个负极极耳30。对正极全极耳和负极全极耳的模切可采用极耳模切设备进行。
在模切所述正极全极耳和所述负极全极耳时，使与所述主体部100的各个正极极片卷绕层分别连接的正极极耳20在所述卷绕方向r的长度b1沿所述卷绕方向r增加，并使与所述主体部100的各个负极极片卷绕层分别连接的负极极耳30在所述卷绕方向r的长度b2沿所述卷绕方向r增加。
在步骤S3中，将所述正极极片10A、所述隔膜10C和所述负极极片10B卷绕成所述电极组件的主体部100，并使所述多个正极极耳20和所述多个负极极耳30位于 所述主体部100在与所述主体部100的卷绕方向r垂直的方向上的同一侧端部。在卷绕时，使正极极耳20和负极极耳30相互错开，使两者分别位于主体部100端部的不同区域。
在步骤S4中，将所述多个正极极耳20和所述多个负极极耳30折弯抚平，以便使多个正极极耳20相互交叠，以及使多个负极极耳30相互交叠。
在本实施例中，通过模切工艺将正极极片上形成的多个正极极耳和负极极片上形成的多个负极极耳设置在卷绕结构的同侧，这样正极极耳对应的集流盘和负极极耳对应的集流盘可分别汇集电流从同侧输出，相比于相关技术中在卷绕结构两端伸出极耳的结构，本实施例可以缩短通过极片到极柱的电子路径，使极耳无需经壳体引导电流，省去了壳体电阻对电池内阻的不利影响和壳体发热对电池内部散热的不利影响，从而降低电池内阻，改善电池散热，提升电池功率和快充能力。
通过使各层极片卷绕层所连接的正极极耳和负极极耳的长度沿卷绕方向增加，可使得极片卷绕后的各个正极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，以及使极片卷绕后的各个负极极耳在弯折抚平时能够根据对应的极片卷绕层的曲率向内交叠并相互靠拢，从而分别形成更齐整的正极极耳组和负极极耳组，便于分隔正负极，并有利于后续的极耳焊接，并且相互隔开的正极极耳以及相互隔开的负极极耳在弯折抚平时不容易产生皱褶，从而降低极耳破碎或皱褶插入极片带来短路的风险。
参考图16，在一些实施例中，所述制造方法还包括：步骤S5。步骤S5可以在步骤S4之后执行。在步骤S5中，将正极集流盘51焊接在已抚平的所述多个正极极耳20上，并将负极集流盘52焊接在已抚平的所述多个负极极耳30上。对已抚平的多个正极极耳和已抚平的多个负极极耳分别焊接正极集流盘和负极集流盘，可获得主体部同侧具有正极集流盘和负极集流盘的电极组件结构。
在上述各实施例中，制造方法还包括：在所述多个正极极耳20和所述多个负极极耳30之间固定绝缘件40，以使所述多个正极极耳20交叠形成的极耳组与所述多个负极极耳30交叠形成的极耳组通过所述绝缘件40隔离。本实施例通过在位于主体部同侧的多个正极极耳和多个负极极耳之间设置绝缘件，可实现两者之间的有效分隔，进一步降低发生短路的风险。设置绝缘件的步骤可以在步骤S4之前执行，以免抚平后的正极极片与抚平后的负极极片相互接触而发生短路。
在一些实施例中，在模切出所述多个正极极耳20的过程中，将所述多个正极极耳 20中的至少一个正极极耳20远离所述正极极片10A一侧的侧边模切出至少一个第一缺口22，以通过所述至少一个第一缺口22将所述正极极耳20沿所述卷绕方向r分隔为多个正极极耳段21。通过将正极极耳的侧边模切出第一缺口来获得分隔的多个正极极耳段可以使正极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
在一些实施例中，在模切出所述多个负极极耳30的过程中，将所述多个负极极耳30中的至少一个负极极耳30远离所述负极极片10B一侧的侧边模切出至少一个第二缺口32，以通过所述至少一个第二缺口32将所述负极极耳30沿所述卷绕方向r分隔为多个负极极耳段31。通过将负极极耳的侧边模切出第二缺口来获得分隔的多个负极极耳段可以使负极极耳在抚平时不容易发生皱褶，降低皱褶带来的极耳破碎风险和皱褶部分插入极片之间导致短路的风险。
基于本公开上述电极组件的各个实施例，本公开实施例还提供了电池单体，包括前述的电极组件。采用前述电极组件的电池单体具有更优的性能，例如更低内阻、更好散热，具有更优的循环性能等。
在本公开的一个方面，提供一种电池，包括前述的电池单体。采用前述电池单体的电池具有更优的性能，例如更低内阻、更好散热，具有更优的循环性能等。
在本公开的一个方面，提供一种用电装置，包括前述的电池。采用前述电池的用电装置具有更优的性能。
虽然已经参考优选实施例对本公开进行了描述，但在不脱离本公开的范围的情况下，可以对其进行各种改进并且可以用等效物替换其中的部件。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。本公开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 (30)

  1. 一种电极组件，包括：
    主体部(100)，包括正极极片(10A)、负极极片(10B)和设置在所述正极极片(10A)和所述负极极片(10B)之间的隔膜(10C)，所述正极极片(10A)、所述隔膜(10C)和所述负极极片(10B)沿卷绕方向(r)卷绕为卷绕结构；
    多个正极极耳(20)，分别与所述卷绕结构中的至少两个正极极片卷绕层连接，并沿所述卷绕方向(r)间隔排布；
    多个负极极耳(30)，分别与所述卷绕结构中的至少两个负极极片卷绕层连接，并沿所述卷绕方向(r)间隔排布；
    其中，所述多个正极极耳(20)和所述多个负极极耳(30)位于所述主体部(100)在与所述卷绕方向(r)垂直的方向上的同一侧端部，与各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)的长度沿所述卷绕方向(r)增加，与各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)的长度沿所述卷绕方向(r)增加。
  2. 根据权利要求1所述的电极组件，其中，所述卷绕结构为绕卷绕轴线(ax)卷绕的圆柱形卷绕结构。
  3. 根据前述任一项权利要求所述的电极组件，其中，所述多个正极极耳(20)在所述主体部(100)的端部相对于所述卷绕轴线(ax)的角度范围与所述多个负极极耳(30)在所述主体部(100)的端部相对于所述卷绕轴线(ax)的角度范围不重合。
  4. 根据前述任一项权利要求所述的电极组件，其中，所述多个正极极耳(20)中的至少一个正极极耳(20)在远离所述正极极片(10A)一侧的侧边具有至少一个第一缺口(22)，所述至少一个第一缺口(22)将所述正极极耳(20)沿所述卷绕方向(r)分隔为多个正极极耳段(21)；和/或
    所述多个负极极耳(30)中的至少一个负极极耳(30)在远离所述负极极片(10B)一侧的侧边具有至少一个第二缺口(32)，所述至少一个第二缺口(32)将所述负极极耳(30)沿所述卷绕方向(r)分隔为多个负极极耳段(31)。
  5. 根据前述任一项权利要求所述的电极组件，其中，各个正极极耳段(21)在所述卷绕方向(r)上的宽度均相同，与各个正极极片卷绕层分别连接的正极极耳(20)中的正极极耳段(21)的数量沿所述卷绕方向(r)增加；各个负极极耳段(31)在所 述卷绕方向(r)上的宽度均相同，与各个负极极片卷绕层分别连接的负极极耳(30)中的负极极耳段(31)的数量沿所述卷绕方向(r)增加。
  6. 根据前述任一项权利要求所述的电极组件，其中，所述多个正极极耳(20)和所述多个负极极耳(30)满足以下至少一种：
    各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最上游的端部位置均位于同一平面；
    各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最下游的端部位置均位于同一平面；
    各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最上游的端部位置均位于同一平面；
    各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最下游的端部位置均位于同一平面。
  7. 根据前述任一项权利要求所述的电极组件，其中，各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最上游的端部位置和位于最下游的端部位置均位于同一平面；和/或
    各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最上游的端部位置和位于最下游的端部位置均位于同一平面。
  8. 根据前述任一项权利要求所述的电极组件，其中，各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最上游的端部位置和各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最上游的端部位置均位于同一平面；
    各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最下游的端部位置和各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最下游的端部位置均位于同一平面。
  9. 根据前述任一项权利要求所述的电极组件，其中，所述卷绕结构为绕卷绕轴线(ax)卷绕的圆柱形卷绕结构，所述多个正极极耳(20)与所述多个负极极耳(30)相对于所述卷绕轴线(ax)对称，或相对于通过所述卷绕轴线(ax)的平面对称。
  10. 根据前述任一项权利要求所述的电极组件，还包括：
    绝缘件(40)，设置在所述主体部(100)连接所述多个正极极耳(20)和所述多个负极极耳(30)一侧的端部，并位于所述多个正极极耳(20)和所述多个负极极耳 (30)之间。
  11. 根据前述任一项权利要求所述的电极组件，其中，所述绝缘件(40)包括绝缘塑胶块。
  12. 根据前述任一项权利要求所述的电极组件，其中，所述卷绕结构为绕卷绕轴线(ax)卷绕的圆柱形卷绕结构，所述圆柱形卷绕结构具有沿轴向贯通的第一中心孔(110)，所述绝缘件(40)具有与所述第一中心孔(110)沿所述卷绕轴线(ax)连通的第二中心孔(41)。
  13. 根据前述任一项权利要求所述的电极组件，其中，所述第一中心孔(110)和所述第二中心孔(41)均为圆孔，且所述第一中心孔(110)的直径D1大于等于所述第二中心孔(41)的直径D2。
  14. 根据前述任一项权利要求所述的电极组件，其中，各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最上游的端部位置均位于第一平面(S1)，各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)上位于最下游的端部位置均位于第二平面(S2)，所述第一平面(S1)在周向上到所述第二平面(S2)的夹角范围θ1满足：
    θ1＝K1*(C/L)，且θ1≤180度；和/或
    各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最上游的端部位置均位于第三平面(S3)，各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)上位于最下游的端部位置均位于第四平面(S4)，所述第三平面(S3)在周向上到所述第四平面(S4)的夹角范围θ2满足：
    θ2＝K2*(C/L)，且θ2≤180度；
    其中，C为采用所述电极组件的电池的容量，L为所述负极极片(10B)的总长度，K1为第一比例参数，K2为第二比例参数。
  15. 根据前述任一项权利要求所述的电极组件，其中，所述电极组件的容量C的单位为安时，所述负极极片(10B)的总长度L的单位为毫米，所述第一比例参数K1大于等于
    Figure PCTCN2022089733-appb-100001
    所述第二比例参数K2大于等于
    Figure PCTCN2022089733-appb-100002
  16. 根据前述任一项权利要求所述的电极组件，其中，所述正极极片(10A)包括正极集流体(11)和在所述正极集流体(11)表面上覆盖的正极活性物质膜层(12)，所述多个正极极耳(20)连接在所述正极集流体(11)沿所述卷绕方向(r)延伸的第 一侧边(16)上，所述正极活性物质膜层(12)从所述正极集流体(11)表面连续延伸到所述多个正极极耳(20)的部分表面，所述负极极片(10B)包括负极集流体(13)、在所述负极集流体(13)表面上覆盖的负极活性物质膜层(14)和在所述负极集流体(13)表面上覆盖的绝缘膜层(15)，所述多个负极极耳(30)连接在所述负极集流体(13)沿所述卷绕方向(r)延伸的第二侧边(17)上，所述绝缘膜层(15)位于所述负极活性物质膜层(14)在第一方向上的前侧，且从所述负极集流体(13)表面连续延伸到所述多个负极极耳(30)的部分表面，所述第一方向为所述多个正极极耳(20)相对于所述正极极片(10A)的延伸方向或所述多个负极极耳(30)相对于所述负极极片(10B)的延伸方向，且所述第一方向与所述卷绕方向(r)垂直。
  17. 根据前述任一项权利要求所述的电极组件，其中，在所述第一方向上，所述正极活性物质膜层(12)在所述多个正极极耳(20)的延伸部分的最前端均位于所述第一侧边(16)的前侧。
  18. 根据前述任一项权利要求所述的电极组件，其中，在所述第一方向上，所述第一侧边(16)位于所述第二侧边(17)的后侧。
  19. 根据前述任一项权利要求所述的电极组件，其中，在所述第一方向上，所述正极活性物质膜层(12)在所述多个正极极耳(20)的延伸部分的最前端位于所述绝缘膜层(15)在所述多个负极极耳(30)的延伸部分的最前端的后侧。
  20. 根据前述任一项权利要求所述的电极组件，其中，所述多个正极极耳(20)中的至少一个正极极耳(20)在远离所述正极极片(10A)一侧的侧边具有至少一个第一缺口(22)，所述至少一个第一缺口(22)将所述正极极耳(20)沿所述卷绕方向(r)分隔为多个正极极耳段(21)，所述至少一个第一缺口(22)的根部在所述第一方向上位于所述隔膜(10C)的前侧；
    所述多个负极极耳(30)中的至少一个负极极耳(30)在远离所述负极极片(10B)一侧的侧边具有至少一个第二缺口(32)，所述至少一个第二缺口(32)将所述负极极耳(30)沿所述卷绕方向(r)分隔为多个负极极耳段(31)，所述至少一个第二缺口(32)的根部在所述第一方向上位于所述隔膜(10C)的前侧。
  21. 根据前述任一项权利要求所述的电极组件，还包括：
    正极集流盘(51)，位于所述多个正极极耳(20)远离所述主体部(100)的一侧，并与已抚平的所述多个正极极耳(20)通过焊接方式固定连接；
    负极集流盘(52)，位于所述多个负极极耳(30)远离所述主体部(100)的一侧， 并与已抚平的所述多个负极极耳(30)通过焊接方式固定连接；
    其中，所述多个正极极耳(20)在所述至少一个第一缺口(22)的根部朝向所述主体部(100)的端部中心折弯并抚平，所述多个负极极耳(30)在所述至少一个第二缺口(32)的根部朝向所述主体部(100)的端部中心折弯并抚平，所述至少一个第一缺口(22)的根部与所述隔膜(10C)在所述第一方向上的第一距离d1大于等于所述正极集流盘(51)的厚度t1的1.5倍，所述至少一个第二缺口(32)的根部与所述隔膜(10C)在所述第一方向上的第二距离d2大于等于所述负极集流盘(52)的厚度t2的1.5倍。
  22. 根据前述任一项权利要求所述的电极组件，其中，相邻正极极耳段(21)之间第一缺口(22)的根部和相邻负极极耳段(31)之间第二缺口(32)的根部位于与所述第一方向垂直的同一平面。
  23. 根据前述任一项权利要求所述的电极组件，还包括：
    绝缘件(40)，设置在所述主体部(100)连接所述多个正极极耳(20)和所述多个负极极耳(30)一侧的端部，并位于所述多个正极极耳(20)和所述多个负极极耳(30)之间，
    其中，在所述第一方向上，所述至少一个第一缺口(22)的根部与所述第二侧边(17)的距离为第三距离d3，所述至少一个第二缺口(32)的根部与所述第二侧边(17)的距离为第四距离d4，所述绝缘件(40)位于所述第二侧边(17)的前侧，且所述绝缘件(40)沿所述第一方向的最前端与所述第二侧边(17)的距离为第五距离d5，所述正极活性物质膜层(12)在所述多个正极极耳(20)的延伸部分的最前端与所述第二侧边(17)的距离为第六距离d6，所述第三距离d3、所述第四距离d4、所述第五距离d5和所述第六距离d6满足：d5<d6，d3<d5，d4<d5。
  24. 一种电池单体，包括：前述任一项权利要求所述的电极组件。
  25. 一种电池，包括权利要求24所述的电池单体。
  26. 一种用电装置，包括权利要求25所述的电池。
  27. 一种电极组件的制造方法，包括：
    提供隔膜(10C)、连接有正极全极耳的正极极片(10A)和连接有负极全极耳的负极极片(10B)；
    将所述正极全极耳模切成沿所述正极极片(10A)的长度方向间隔排布的多个正极极耳(20)，以及将所述负极全极耳模切成沿所述负极极片(10B)的长度方向间隔 排布的多个负极极耳(30)；
    将所述正极极片(10A)、所述隔膜(10C)和所述负极极片(10B)卷绕成所述电极组件的主体部(100)，并使所述多个正极极耳(20)和所述多个负极极耳(30)位于所述主体部(100)在与所述主体部(100)的卷绕方向(r)垂直的方向上的同一侧端部；
    将所述多个正极极耳(20)和所述多个负极极耳(30)折弯抚平；
    其中，在模切所述正极全极耳和所述负极全极耳时，使与所述主体部(100)的各个正极极片卷绕层分别连接的正极极耳(20)在所述卷绕方向(r)的长度沿所述卷绕方向(r)增加，并使与所述主体部(100)的各个负极极片卷绕层分别连接的负极极耳(30)在所述卷绕方向(r)的长度沿所述卷绕方向(r)增加。
  28. 根据权利要求27所述的制造方法，还包括：
    在所述多个正极极耳(20)和所述多个负极极耳(30)之间固定绝缘件(40)，以使所述多个正极极耳(20)交叠形成的极耳组与所述多个负极极耳(30)交叠形成的极耳组通过所述绝缘件(40)隔离。
  29. 根据前述任一项权利要求所述的制造方法，还包括：
    将正极集流盘(51)焊接在已抚平的所述多个正极极耳(20)上，并将负极集流盘(52)焊接在已抚平的所述多个负极极耳(30)上。
  30. 根据前述任一项权利要求所述的制造方法，其中，在模切出所述多个正极极耳(20)的过程中，将所述多个正极极耳(20)中的至少一个正极极耳(20)远离所述正极极片(10A)一侧的侧边模切出至少一个第一缺口(22)，以通过所述至少一个第一缺口(22)将所述正极极耳(20)沿所述卷绕方向(r)分隔为多个正极极耳段(21)；和/或
    在模切出所述多个负极极耳(30)的过程中，将所述多个负极极耳(30)中的至少一个负极极耳(30)远离所述负极极片(10B)一侧的侧边模切出至少一个第二缺口(32)，以通过所述至少一个第二缺口(32)将所述负极极耳(30)沿所述卷绕方向(r)分隔为多个负极极耳段(31)。
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