WO2023088434A1 - 极片和电池 - Google Patents

极片和电池 Download PDF

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Publication number
WO2023088434A1
WO2023088434A1 PCT/CN2022/132908 CN2022132908W WO2023088434A1 WO 2023088434 A1 WO2023088434 A1 WO 2023088434A1 CN 2022132908 W CN2022132908 W CN 2022132908W WO 2023088434 A1 WO2023088434 A1 WO 2023088434A1
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WO
WIPO (PCT)
Prior art keywords
extension section
pole piece
tab
current collector
groove
Prior art date
Application number
PCT/CN2022/132908
Other languages
English (en)
French (fr)
Inventor
彭宁
Original Assignee
珠海冠宇电池股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 珠海冠宇电池股份有限公司 filed Critical 珠海冠宇电池股份有限公司
Publication of WO2023088434A1 publication Critical patent/WO2023088434A1/zh

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • 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
    • 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
    • H01M50/531—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
    • 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

Definitions

  • the present application relates to the technical field of batteries, in particular to a pole piece and a battery.
  • Lithium-ion batteries have the advantages of large capacity, small size, light weight and environmental protection, and have been widely used in digital electronic products and electric vehicles and other industries.
  • a pole piece may include a pole piece body and a pole lug, and the pole piece is welded on the pole piece body.
  • the embodiments of the present application provide a pole piece and a battery, which can reduce the internal resistance of the tab and improve the overcurrent performance of the battery.
  • the first aspect of the embodiment of the present application provides a pole piece, including: a pole piece body and a pole piece body, a part of the pole piece body and a part of the pole piece body are stacked, and the pole piece and the pole piece body are electrically connected to each other at the stacked position ;
  • the tab includes a connected first extension section and a second extension section, at least part of the first extension section is located in an overlapping position, and the projection of the second extension section on the plane where the pole piece body is located does not overlap with the pole piece body;
  • the thickness of the first extension is smaller than the thickness of the second extension.
  • the pole piece body is electrically connected with the external circuit by the pole piece.
  • Part of the tab and part of the pole piece body are stacked and welded, and the tab and the pole piece body are electrically connected to each other at the stacked position.
  • the tab includes a connected first extension section and a second extension section, at least part of the first extension section is located at a stacked position, and the first extension section is used for electrical connection with the pole piece body.
  • the projection of the second extension section on the plane where the pole piece body is located does not overlap with the pole piece body, and the second extension section is used for electrical connection with an external circuit.
  • the pole piece body and part of the tabs overlapped with the pole piece body affect the thickness of the cell, that is, the first extension section at the overlapping position affects the thickness of the cell.
  • the second extension section does not overlap with the pole piece body in the thickness direction, that is, does not overlap with the battery cell in the thickness direction, and has no influence on the thickness of the battery cell. Therefore, by setting the thickness of the first extension section to be smaller than the thickness of the second extension section. In this way, the first extension section is relatively thin, which can reduce the influence of the tab on the thickness of the battery cell and ensure the energy density of the battery.
  • the second extension section can be set thicker, so that the overall resistance of the tab is smaller, thereby improving the overcurrent capability of the battery and further improving the performance of the battery.
  • an adapter is provided between the first extension section and the second extension section, the first extension section and the second extension section are connected through the adapter section, and the adapter section is located at the pole piece body.
  • the projection on the plane does not overlap with the pole piece body.
  • the first end of the first extension section and the first end of the second extension section are overlapped in the thickness direction of the lug, and the overlapping portion of the first extension section and the second extension section forms a transition department.
  • the end surface of the first end of the first extension section is opposite to the end surface of the first end of the second extension section, and are respectively connected to opposite ends of the transition portion;
  • the thickness of the transfer portion gradually increases from the first extension section to the second extension section.
  • the outer surface of the adapter part is an arc surface, and the arc surface is curved toward the center of the adapter part in the thickness direction;
  • the curved angle of the arc surface is a rounded corner, and the radius of the rounded corner is 0.1mm-2mm.
  • the pole piece body includes: a current collector and an active material layer, the current collector includes two functional surfaces oppositely arranged, and the active material layers are respectively arranged on the two functional surfaces;
  • the active material layer on one of the functional surfaces of the pole piece body has a groove, and the bottom wall of the groove is the functional surface of the current collector;
  • the projection of the groove on the current collector, the active material layer on the side of the current collector facing away from the groove is within the projection of the current collector
  • the tab is welded to the current collector in the groove to form a weld mark, at least part of the weld mark is located on the side of the tab away from the current collector, and protrudes toward the side away from the current collector to form a first protrusion.
  • the solder print runs through the tab, and the solder print is located in a partial area close to the tab in the thickness direction of the current collector;
  • the welding mark runs through the tab and the current collector, and the welding mark on the side of the current collector away from the tab protrudes toward the side away from the tab to form a second protrusion, and the side of the current collector away from the tab protrudes to form a second protrusion.
  • the active material layer on one side of the groove covers the second protrusion;
  • the welding print includes an outer edge part and a middle part, and the outer edge part is set outside the middle part;
  • the middle part runs through the tab, and the middle part is located in a part of the area close to the tab in the thickness direction of the current collector;
  • the outer edge part runs through the tab and the current collector.
  • the outer edge of the current collector on the side away from the tab protrudes toward the side away from the tab to form a second protrusion.
  • the active material layer on one side of the groove covers the second protrusion.
  • the surface of the tab away from the current collector is covered with a protective layer, and the protective layer completely covers the groove;
  • the depth of the groove ranges from 0.01mm to 0.2mm;
  • the length of the groove along the width direction of the pole piece ranges from 1mm to 40mm;
  • the length of the groove along the length direction of the pole piece ranges from 1mm to 30mm;
  • the distance between the center of the weld mark and the outer edge of the weld mark ranges from 0.05mm to 2.5mm;
  • the protrusion height of the first protrusion is less than or equal to 0.1mm.
  • the width of the first extension section is equal to the width of the second extension section
  • the width of the first extension section is greater than the width of the second extension section.
  • the width of the tab gradually decreases from the first extension section to the second extension section.
  • the shape of the tab is trapezoidal or triangular.
  • a notch is provided on the edge of the pole piece body, and the notch is located on the edge of the groove;
  • At least part of the transition portion is located in the notch.
  • the thickness range of the first extension section is 0.005mm-0.1mm;
  • the width range of the first extension section is 1mm-30mm;
  • the length range of the first extension section is 5mm-30mm;
  • the thickness range of the second extension section is 0.01mm-0.5mm;
  • the width range of the second extension section is 1mm-20mm;
  • the length of the second extension section is in the range of 2mm-20mm.
  • the length of the transition part ranges from 0.1 mm to 10 mm;
  • the width range of the transition part is 1mm-20mm.
  • it also includes an auxiliary adhesive layer, the tabs are inserted into the auxiliary adhesive layer, and the projection of the auxiliary adhesive layer on the plane where the pole piece body is located does not overlap with the pole piece body;
  • the thickness range of the auxiliary adhesive layer is 0.1mm-3mm;
  • the width range of the auxiliary adhesive layer is 2mm-40mm;
  • the length of the auxiliary adhesive layer ranges from 2 mm to 40 mm.
  • a second aspect of the embodiments of the present application provides a battery, including the pole piece in the above first aspect.
  • the pole piece body is electrically connected with the external circuit by the pole piece.
  • Part of the tab and part of the pole piece body are stacked and welded, and the tab and the pole piece body are electrically connected to each other at the stacked position.
  • the tab includes a connected first extension section and a second extension section, at least part of the first extension section is located at a stacked position, and the first extension section is used for electrical connection with the pole piece body.
  • the projection of the second extension section on the plane where the pole piece body is located does not overlap with the pole piece body, and the second extension section is used for electrical connection with an external circuit.
  • the pole piece body and part of the tabs overlapped with the pole piece body affect the thickness of the cell, that is, the first extension section at the overlapping position affects the thickness of the cell.
  • the second extension section does not overlap with the pole piece body in the thickness direction, that is, does not overlap with the battery cell in the thickness direction, and has no influence on the thickness of the battery cell. Therefore, by setting the thickness of the first extension section to be smaller than the thickness of the second extension section. In this way, the first extension section is relatively thin, which can reduce the influence of the tab on the thickness of the battery cell and ensure the energy density of the battery.
  • the second extension section can be set thicker, so that the overall resistance of the tab is smaller, thereby improving the overcurrent capability of the battery and further improving the performance of the battery.
  • Figure 1 is a cross-sectional view of a pole piece provided by an embodiment of the present application.
  • Fig. 2 is a top view of a pole piece provided by the embodiment of the present application.
  • Fig. 3 is a front view of a tab provided in the embodiment of the present application.
  • Fig. 4 is the top view junction diagram of Fig. 3;
  • Fig. 5 is a front view of another tab provided in the embodiment of the present application.
  • Figure 6 is a top view of Figure 5;
  • Fig. 7 is a top view of a tab provided in the embodiment of the present application.
  • Fig. 8 is a top view of another tab provided by the embodiment of the present application.
  • Fig. 9 is a top view of the auxiliary adhesive layer provided by the embodiment of the present application on the side of the transition part close to the first extension section;
  • Fig. 10 is a top view of the auxiliary adhesive layer provided in the embodiment of the present application on the side of the transition part away from the first extension section;
  • Fig. 11 is a top view of the transition part located in the gap provided by the embodiment of the present application.
  • Fig. 12 is a top view of the transition part located outside the gap provided by the embodiment of the present application.
  • Fig. 13 is a top view of the partial overlapping of the protective layer and the auxiliary adhesive layer provided by the embodiment of the present application.
  • a pole piece may include a pole piece body and a pole lug, and the pole piece is welded on the pole piece body.
  • the pole piece is used to form the cell of the battery. If the thickness of the tab is larger, the thickness of the cell will be increased, resulting in a lower energy density of the cell. In order to avoid the low energy density of the cell due to too thick tabs, the tabs can be set thinner, so that the tabs have less influence on the thickness of the cell. However, when the tab is thinner, the resistance of the tab is larger, the tab generates more heat when energized, and the overcurrent capability of the tab is poor, which will also affect the performance of the battery.
  • the embodiment of the present application provides a pole piece and a battery.
  • the tab electrically connects the pole piece body with an external circuit.
  • Part of the tab and part of the pole piece body are stacked and welded, and the tab and the pole piece body are electrically connected to each other at the stacked position.
  • the tab includes a connected first extension section and a second extension section, at least part of the first extension section is located at a stacked position, and the first extension section is used for electrical connection with the pole piece body.
  • the projection of the second extension section on the plane where the pole piece body is located does not overlap with the pole piece body, and the second extension section is used for electrical connection with an external circuit.
  • the pole piece body and part of the tabs overlapped with the pole piece body affect the thickness of the cell, that is, the first extension section at the overlapping position affects the thickness of the cell.
  • the second extension section does not overlap with the pole piece body in the thickness direction, that is, does not overlap with the battery cell in the thickness direction, and has no influence on the thickness of the battery cell. Therefore, by setting the thickness of the first extension section to be smaller than the thickness of the second extension section. In this way, the first extension section is relatively thin, which can reduce the influence of the tab on the thickness of the battery cell and ensure the energy density of the battery.
  • the second extension section can be set thicker, so that the overall resistance of the tab is smaller, thereby improving the overcurrent capability of the battery and further improving the performance of the battery.
  • An embodiment of the present application provides a battery, and the battery includes a cell, which refers to an electrochemical cell installed inside the battery and includes a positive electrode and a negative electrode. Batteries are generally not used directly, and batteries for charging/discharging can be formed by installing the batteries inside the battery case. Since the cell is the power storage part of the battery, the quality of the cell directly determines the quality of the battery.
  • the cell may include a first pole piece, a diaphragm and a second pole piece, the diaphragm is located between the adjacent first pole piece and the second pole piece, and the diaphragm is used to electrically insulate the first pole piece and the second pole piece.
  • one of the first pole piece and the second pole piece can be a negative pole piece; the other of the first pole piece and the second pole piece can be a positive pole piece.
  • the battery cell may be a wound-type battery cell.
  • both the first pole piece and the second pole piece are one, and the first pole piece, the diaphragm and the second pole piece stacked in sequence are wound around the winding center to form a winding structure.
  • the battery cell may be a laminated battery cell.
  • there are multiple first pole pieces and multiple second pole pieces and the multiple first pole pieces and the multiple second pole pieces are sequentially stacked along the same direction, and every adjacent first pole piece and second pole piece A diaphragm is arranged between the two pole pieces to electrically insulate the first pole piece and the second pole piece.
  • the embodiment of the present application provides a pole piece 100, which can be used for the battery in the above embodiment, and the pole piece 100 can be the first pole piece of the above embodiment, or can be the above pole piece The second pole piece of the embodiment.
  • the pole piece 100 includes a pole piece body 10 and a pole lug 20 , and the pole piece body 10 is used to electrically connect the pole piece body 10 with an external circuit.
  • Part of the tab 20 and part of the pole piece body 10 are stacked on each other, so as to facilitate the electrical connection between the tab 20 and the pole piece body 10 through the overlapping position.
  • the material of the tab 20 may be copper, nickel, aluminum or other composite metal materials, which is not limited in this embodiment.
  • the tab 20 may include a connected first extension section 21 and a second extension section 22, at least part of the first extension section 21 is located in an overlapping position, and the first extension section 21 is used to connect with the pole piece.
  • the body 10 is electrically connected.
  • the first extension section 21 may be partly located at the overlapping position, or the first extension section 21 may also be entirely located at the overlapping position, which is not limited in this embodiment.
  • the projection of the second extension section 22 on the plane where the pole piece body 10 is located does not overlap with the pole piece body 10 .
  • the second extension section 22 does not overlap with the battery cell in the thickness direction, and the second extension section 22 will not affect the thickness of the battery cell and will not affect the energy density of the battery.
  • the pole piece body 10 is electrically connected to an external circuit through the first extension section 21 and the second extension section 22 .
  • the materials of the first extension section 21 and the second extension section 22 can be the same or different.
  • the thickness of the first extension section 21 is H1
  • the thickness of the second extension section 22 is H2, wherein H1 is smaller than H2.
  • the thickness H1 of the first extension section 21 may range from 0.005 mm to 0.1 mm.
  • the thickness H1 of the first extension section 21 may be 0.005mm, 0.01mm, 0.03mm, 0.05mm, 0.07mm or 0.1mm, etc. Therefore, it can be avoided that the first extension section 21 is too thin, and the strength of the first extension section 21 is low. It can also prevent the first extension section 21 from being too thick, which will affect the thickness of the battery cell.
  • the width of the first extension section 21 is W1 , and the width W1 of the first extension section 21 may range from 1 mm to 30 mm.
  • the width W1 of the first extension section 21 may be 1mm, 5mm, 15mm, 20mm, 25mm or 30mm and so on. Therefore, it can be avoided that the first extension section 21 is too narrow, the connection area between the first extension section 21 and the pole piece body 10 is small, and the connection strength between the first extension section 21 and the pole piece body 10 is low. It can also prevent the first extension section 21 from being too wide and occupying more internal space of the battery.
  • the length of the first extension section 21 is L1, and the length L1 of the first extension section 21 may range from 5 mm to 30 mm.
  • the length L1 of the first extension section 21 may be 5mm, 15mm, 20mm, 25mm or 30mm and so on.
  • the principle is similar to the width W1 of the first extension section 21 , and will not be repeated here.
  • the thickness H2 of the second extension section 22 may range from 0.01 mm to 0.5 mm.
  • the thickness H2 of the second extension segment 22 can be 0.01 mm, 0.05 mm, 0.1 mm, 0.2 mm, 0.3 mm or 0.5 mm, etc. Therefore, it can avoid that the second extension section 22 is too thin, its resistance is relatively large, and its overcurrent capability is poor. It can also prevent the second extension section 22 from being too thick and occupying more internal space of the battery.
  • the width of the second extension section 22 is W2 , and the width W2 of the second extension section 22 may range from 1 mm to 20 mm.
  • the width W2 of the second extension section 22 may be 1 mm, 5 mm, 15 mm or 20 mm. Therefore, it can avoid that the second extension section 22 is narrow, its resistance is large, and its overcurrent capability is poor. It can also prevent the second extension section 22 from being too wide and occupying more internal space of the battery.
  • the length of the second extension section 22 is L2, and the length L2 of the second extension section 22 may range from 2 mm to 20 mm.
  • the length L2 of the second extension section 22 may be 2mm, 5mm, 15mm or 20mm. Therefore, it can be avoided that the length L2 of the second extension section 22 is too short, and the area that can be connected with the external circuit is small, resulting in a low connection strength with the external circuit. It can also prevent the length L2 of the second extension section 22 from being too long and occupying more internal space of the battery.
  • a transfer portion 23 is provided between the first extension segment 21 and the second extension segment 22 , and the transfer portion 23 is shown in a dashed box in FIG. 3 .
  • the first extension section 21 and the second extension section 22 are connected by a transition portion 23 , and the transition portion 23 is a transition area between the first extension section 21 and the second extension section 22 .
  • the projection of the transfer portion 23 on the plane where the pole piece body 10 is located does not overlap with the pole piece body 10, so that after the pole piece 100 forms a cell, the transfer portion 23 and the cell do not overlap in the thickness direction. Overlapping, the transfer portion 23 will not affect the thickness of the battery core, and will not cause the battery core to be uneven.
  • the first end of the first extension section 21 and the first end of the second extension section 22 are overlapped in the thickness direction of the tab 20 .
  • the first end of the first extension section 21 is an end close to the second extension section 22
  • the first end of the second extension section 22 is an end close to the first extension section 21 .
  • the overlapping portion of the first extension section 21 and the second extension section 22 forms a transition portion 23 .
  • the transition portion 23 is used to connect the first extension section 21 and the second extension section 22 together. Since the transition section 23 makes the contact area between the first extension section 21 and the second extension section 22 larger, the first extension section 21
  • the connection strength with the second extension section 22 is relatively high.
  • the first extension section 21 and the second extension section 22 can be connected by integral molding, riveting, ultrasonic welding, resistance welding or laser welding.
  • the first extension section 21 and the second extension section 22 are connected by welding, there may be multiple welding marks formed on the transfer portion 23 , and the plurality of welding marks are arranged at intervals.
  • the individual soldering marks are small, so that the input energy required for each soldering mark is small, avoiding the phenomenon of over-welding or welding-through of the first extension section 21 or the second extension section 22 caused by excessive heat, and ensuring the tab 20 performance.
  • the width W1 of the first extension section 21 may be greater than or equal to the width W2 of the second extension section 22 . Wherein, when the width W1 of the first extension section 21 is equal to the width W2 of the second extension section 22 , the tab 20 is more beautiful. When the width W1 of the first extension section 21 is greater than the width W2 of the second extension section 22, the contact area between the first extension section 21 and the pole piece body 10 is larger, and the distance between the first extension section 21 and the pole piece body 10 can be increased. the connection strength between them.
  • the end surface of the first end of the first extension section 21 is opposite to the end surface of the first end of the second extension section 22 .
  • the first end of the first extension section 21 is an end close to the second extension section 22
  • the first end of the second extension section 22 is an end close to the first extension section 21 .
  • a first end of the first extension section 21 is connected to one end of the transition part 23
  • a first end of the second extension section 22 is connected to the opposite end of the transition part 23 .
  • the first extension section 21 and the second extension section 22 do not overlap in the thickness direction, the transfer portion 23 can be set thinner, and the transfer portion 23 occupies less internal space of the battery.
  • the first extension section 21 and the second extension section 22 can be connected by integral molding, ultrasonic welding, resistance welding or laser welding.
  • first extension section 21 and the second extension section 22 are connected by integral molding.
  • the first extension section 21, the transition part 23 and the second extension section 22 can be integrally formed, and one end can be rolled on the thicker tab 20 to form the first extension section 21, and the other end can directly form the second extension section.
  • Section 22, the transition area between the two forms the transition part 23, and the process is relatively simple.
  • the connection strength between the first extension section 21 , the transition portion 23 and the second extension section 22 is relatively high. Since the first extension section 21 is formed by rolling, the first extension section 21 becomes thinner and wider after rolling, and the width W1 of the first extension section 21 is greater than the width W2 of the second extension section 22 . After the area of the first extension section 21 becomes larger, the contact area with the pole piece body 10 increases, which can increase the connection strength between the first extension section 21 and the pole piece body 10 . Of course, the first extension section 21 can also be cut so that the width W1 of the first extension section 21 is the same as the width W2 of the second extension section 22, so that the tab 20 as a whole is more beautiful, which is not done in this embodiment. limit.
  • the width of the tab 20 gradually decreases from the first extension section 21 to the second extension section 22 .
  • the shape of the tab 20 may be triangular, trapezoidal or other shapes, which is not limited in this embodiment.
  • the thickness of the transition portion 23 increases gradually from the first extension section 21 to the second extension section 22 .
  • the transition between the first extension section 21 and the second extension section 22 is relatively gentle, which can avoid stress concentration at the transition portion 23 .
  • the two outer surfaces of the transfer portion 23 spaced along the thickness direction may be arc surfaces, and the arc surfaces are curved toward the center of the transfer portion 23 in the thickness direction.
  • the curved angle of the arc surface may be a rounded corner, and the radius of the rounded corner may range from 0.1 mm to 2 mm.
  • the radius of the fillet can be 0.1mm, 0.3mm, 0.5mm, 1mm, 1.5mm or 2mm, etc.
  • the radius of the fillet is too small, which will lead to a large degree of curvature of the arc surface, and cannot form a smooth transition. It can also avoid excessive fillet radius, resulting in too long transition portion 23, occupying a large volume, and affecting other structural layouts inside the battery.
  • the length of the transition portion 23 is L3, and the length L3 of the transition portion 23 may range from 0.1 mm to 10 mm.
  • the length L3 of the transition portion 23 may be 0.1 mm, 1 mm, 3 mm, 5 mm, or 10 mm. Therefore, it can be avoided that the transition portion 23 is too short, and the connection strength between the first extension section 21 and the second extension section 22 is low. It can also prevent the transition part 23 from being too long, which will affect other structural layouts inside the battery.
  • the width of the transition portion 23 is W3, and the width W3 of the transition portion 23 may range from 1 mm to 20 mm.
  • the width W3 of the transition portion 23 may be 1 mm, 5 mm, 10 mm, 15 mm, or 20 mm. Its principle is similar to the length L3 of the transfer portion 23 and will not be repeated here.
  • the pole piece body 10 includes a current collector 11 and an active material layer 12.
  • the pole piece 100 can be a negative pole piece or a positive pole piece, and it can be specified according to the current collector 11 and each active material layer.
  • the specific choice of material for layer 12 is determined.
  • the pole sheet 100 is a positive electrode sheet; when the current collector 11 is copper foil, the material of the active material layer 12 When it is a negative electrode active material such as graphite or silicon base, the pole piece 100 is a negative pole piece.
  • the current collector 11 includes two opposite functional surfaces, and the active material layer 12 is respectively disposed on the two functional surfaces.
  • the functional surfaces of the current collector 11 refer to the largest and opposite surfaces of the current collector 11 for coating the active material layer 12 .
  • the active material layer 12 in the pole piece 100 of the present application may be coated on only one functional surface of the current collector 11 , or coated on both functional surfaces of the current collector 11 at the same time.
  • the active material layer 12 on one of the functional surfaces is provided with a groove 121 , and the groove 121 exposes part of the functional surface of the current collector 11 .
  • the groove 121 can be formed by cleaning and removing the corresponding part of the active material layer 12 to expose the current collector 11 . Since the active material layer 12 at the groove 121 is removed, the thickness of the battery cell can be reduced.
  • the cleaning method may be laser cleaning, mechanical cleaning, or styrofoam cleaning, and the application does not limit the cleaning method.
  • the tab 20 is electrically connected to the exposed functional surface in the groove 121 .
  • At least part of the first extension section 21 is located in the groove 121 .
  • part of the first extension section 21 may be located in the groove 121 , or all of the first extension section 21 may be located in the groove 121 .
  • a surface of the tab 20 away from the current collector 11 is covered with a protective layer 40 , and the protective layer 40 completely covers the groove 121 .
  • the protective layer 40 can prevent the welding burr formed by the tab 20 and the current collector 11 from piercing the separator and causing a short circuit between adjacent positive and negative electrodes in the battery.
  • the protective layer 40 has a fixing effect on the tab 20 and further fixes the tab 20 on the pole piece 100 .
  • the groove 121 can be close to the edge of the pole piece 100 in the width direction, and the side of the groove 121 close to the edge is open. That is, there is no active material layer 12 on the outer side of the groove 121 close to the edge, and the active material layer 12 is disposed on the outer side of the groove 121 away from the edge.
  • the length of the groove 121 is smaller than the length of the current collector 11 .
  • the tab 20 and the current collector 11 can be connected by laser welding, wherein the laser welding can be irradiated from the side of the tab 20 away from the current collector 11 to the tab 20 for welding, and the tab 20 and the current collector in the groove 121 11 is welded to form a welding mark, at least part of the welding mark is located on the side of the tab 20 away from the current collector 11 , and protrudes toward the side away from the current collector 11 to form a first protrusion.
  • the height of the first protrusion is less than or equal to 0.1 mm.
  • the protrusion height of the first protrusion may be 0.01 mm, 0.03 mm, 0.05 mm, 0.07 mm, 0.09 mm or 0.1 mm, etc., which is not limited in this embodiment. Therefore, it can be avoided that the first protrusion is too high, and it is easy to pierce the adjacent diaphragm in the battery, resulting in a short circuit between the positive and negative electrodes of the battery.
  • solder marks there may be multiple solder marks, and the multiple solder marks are arranged at intervals and jointly form the welding area 30 .
  • the input energy for forming a single soldering mark is small, which can reduce the impact on the active material layer 12 near the soldering area 30 .
  • the distance between the center of the weld mark and the outer edge of the weld mark may range from 0.05 mm to 2.5 mm.
  • the distance may be 0.05 mm, 0.25 mm, 0.5 mm, 1 mm, 1.5 mm or 2.5 mm, etc., which is not limited in this embodiment.
  • the active material layer 12 located on the side of the current collector 11 away from the groove 121 is within the projection of the current collector 11 . That is, the active material layer 12 on the back of the groove 121 is not removed, the exposed area of the current collector 11 is small, and the activity of the pole piece 100 is high.
  • the depth of the groove 121 ranges from 0.01 mm to 0.2 mm.
  • the depth of the groove 121 may be 0.01mm, 0.03mm, 0.04mm, 0.05mm, 0.07mm, 0.1mm or 0.2mm. Therefore, the active material layer 12 can be avoided from being too thin, and the energy density of the battery is low. It can also avoid that the active material layer 12 is too thick, the active material layer 12 close to the surface of the current collector 11 cannot be utilized, and the utilization rate of the active material in the active material layer 12 is low.
  • the length of the groove 121 along the width direction of the pole piece 100 may range from 1 mm to 40 mm.
  • the length can be 1mm, 2mm, 5mm, 10mm, 15mm, 20mm, 30mm or 40mm, etc. Therefore, it can be avoided that the length is too small, resulting in a small connectable area between the tab 20 and the current collector 11 . It can also avoid that the length is too large, and the active material layer 12 will be removed more, which will greatly affect the energy density of the battery.
  • the length of the groove 121 along the length direction of the pole piece 100 may range from 1 mm to 30 mm.
  • the length can be 1 mm, 2 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm or 30 mm and so on.
  • the principle is similar to that of the length value along the width direction, and will not be repeated here.
  • the welding print runs through the tab 20, and the welding print is located in a part of the area close to the tab 20 in the thickness direction of the current collector 11 .
  • the welding mark is formed on the side of the tab 20 away from the current collector 11, but no welding mark is formed on the side of the current collector 11 away from the tab 20, and the side of the current collector 11 away from the side of the tab 20 is a plane . In this way, the solder print has less influence on the active material layer 12 on the side of the current collector 11 away from the tab 20 .
  • the welding print runs through the tab 20 and the current collector 11 .
  • welding marks can be observed on the side of the tab 20 facing away from the current collector 11 and the side of the current collector 11 facing away from the tab 20 .
  • the solder mark on the side of the current collector 11 away from the tab 20 protrudes toward the side away from the tab 20 , thereby forming a second protrusion.
  • the active material layer 12 on the side of the current collector 11 facing away from the groove 121 covers the second protrusion, which can reduce the impact of soldering on the separator on this side.
  • the solder print includes an outer edge portion and a middle portion, and the outer edge portion is arranged around the outer side of the middle portion.
  • the outer edge passes through the tab 20 and the current collector 11 , and the outer edge of the current collector 11 on the side away from the tab 20 protrudes toward the side away from the tab 20 .
  • the outer edge of the solder mark can be observed on the surface of the current collector 11 facing away from the tab 20 .
  • the outer edge of the current collector 11 on the side away from the tab 20 protrudes toward the side away from the tab 20 to form a second protrusion.
  • the active material layer 12 on the side of the current collector 11 away from the groove 121 covers the second protrusion, which can reduce the influence of the outer edge on the diaphragm on this side.
  • the middle portion passes through the tab 20 , and the middle portion is located in a partial area of the current collector 11 close to the tab 20 in the thickness direction. At this time, the middle portion cannot be observed on the surface of the current collector 11 facing away from the tab 20 .
  • a notch 13 is provided on the edge of the pole piece body 10 , and the notch 13 is shown in a dashed box in FIG. 11 .
  • the notch 13 is located at the edge of the groove 121 , and the notch 13 runs through the pole piece body 10 along the thickness direction, that is, the current collector 11 and the active material layer 12 at the notch 13 are removed.
  • An accommodating space is formed at the notch 13 , and at least part of the transfer portion 23 is located in the notch 13 , so that the transfer portion 23 is located in the accommodating space formed by the notch 13 . In this way, after the cell is formed, the transfer portion 23 in the notch 13 will be located inside the cell, and the cell has a protective effect on this part of the transfer portion 23 .
  • the transfer portion 23 at the notch 13 will not affect the thickness of the battery cell.
  • the transition portion 23 can be partially located in the notch 13, so as to protect part of the transition portion 23.
  • the transfer portion 23 may be completely located in the notch 13 to form protection for the entire transfer portion 23 , which is not limited in this embodiment.
  • an auxiliary adhesive layer 50 may also be provided on the pole piece 100 , and part of the tabs 20 are inserted into the auxiliary adhesive layer 50 .
  • the exterior of the battery core can be wrapped with a plastic casing to insulate the battery core from the outside.
  • the auxiliary adhesive layer 50 can be used to seal (using hot-melt sealing) the gap between the tab 20 and the plastic package.
  • the projection of the auxiliary glue layer 50 on the plane where the pole piece body 10 is located does not overlap with the pole piece body 10 . In this way, after the pole piece 100 is formed into a cell, the auxiliary adhesive layer 50 does not overlap with the cell in the thickness direction, and the auxiliary adhesive layer 50 will not affect the thickness of the cell.
  • the auxiliary adhesive layer 50 and the protective layer 40 can partially overlap in the thickness direction of the pole piece 100, so that there is no tab 20 leaking between the auxiliary adhesive layer 50 and the protective layer 40, and the gap between the two can be adjusted.
  • the tabs 20 play a protective role.
  • there may be a partial gap between the auxiliary adhesive layer 50 and the protective layer 40 so that the setting position of the auxiliary adhesive layer 50 is more free.
  • the auxiliary adhesive layer 50 may be located on a side of the transition portion 23 away from the first extension section 21 , that is, on the second extension section 22 . In this way, the transfer portion 23 is located outside the plastic package, and the volume of the plastic package is small.
  • the auxiliary adhesive layer 50 may be located on the side of the transition portion 23 away from the second extension section 22 , that is, on the first extension section 21 . In this way, the adapter portion 23 can be disposed in the plastic casing to protect the adapter portion 23 .
  • the auxiliary adhesive layer 50 may cover at least part of the transition portion 23 .
  • the auxiliary adhesive layer 50 has a protective effect on the covered part of the transfer portion 23 .
  • the auxiliary adhesive layer 50 may cover part of the transition portion 23 , or the auxiliary adhesive layer 50 may cover the entire transition portion 23 .
  • the thickness of the auxiliary adhesive layer 50 is H4, and the thickness H4 of the auxiliary adhesive layer 50 ranges from 0.1 mm to 3 mm.
  • the thickness H4 of the auxiliary adhesive layer 50 may be 0.1 mm, 1 mm, 1.5 mm, 2 mm or 3 mm and so on. Therefore, it can avoid that the auxiliary adhesive layer 50 is too thin, which is easy to wear and fail. It can also prevent the auxiliary adhesive layer 50 from being too thick, resulting in poor flatness of the joint between the auxiliary adhesive layer 50 and the plastic package, which will affect the sealing performance.
  • the width of the auxiliary adhesive layer 50 is W4, and the width W4 of the auxiliary adhesive layer 50 ranges from 2 mm to 40 mm.
  • the width W4 of the auxiliary adhesive layer 50 may be 2mm, 10mm, 15mm, 20mm, 30mm, or 40mm.
  • the length of the auxiliary adhesive layer 50 is L4, and the length L4 of the auxiliary adhesive layer 50 ranges from 2 mm to 40 mm.
  • the length L4 of the auxiliary adhesive layer 50 may be 2mm, 10mm, 15mm, 20mm, 30mm, or 40mm.
  • the principle is similar to the width W4 of the auxiliary adhesive layer 50 , and will not be repeated here.
  • the width direction of the pole piece 100 is the direction shown by Y in FIG. 2 ; the length direction of the pole piece 100 is the direction shown by X in FIG. 2 .
  • the lengths of the first extension section 21 , the second extension section 22 , the transition portion 23 , the auxiliary adhesive layer 50 and the tab 20 are consistent with the width direction of the pole piece 100 .
  • the widths of the first extension section 21 , the second extension section 22 , the transition portion 23 , the auxiliary adhesive layer 50 and the tab 20 are consistent with the length direction of the pole piece 100 .
  • the width and length in the embodiments of the present application are only for the convenience of description, and do not imply any limitation to any size. For example, width may be greater than, less than, or equal to length.

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  • Manufacturing & Machinery (AREA)
  • Connection Of Batteries Or Terminals (AREA)

Abstract

本申请提供一种极片和电池，极片包括极片本体和极耳，部分极耳与部分极片本体相互叠设，且极耳和极片本体在叠设位置相互电性连接；极耳包括连接的第一延伸段和第二延伸段，至少部分第一延伸段位于叠设位置，第二延伸段在极片本体所在的平面上的投影，与极片本体互不重叠；第一延伸段的厚度小于第二延伸段的厚度。这样，第一延伸段可以设置得较薄，降低极耳对电芯厚度的影响，保证电池的能量密度。而第二延伸段可以设置得较厚，极耳的整体电阻较小，从而提高了电池的过流能力，提升了电池的性能。因此，本申请提供的极片和电池，能够降低极耳的内阻，提升电池的过流性能。

Description

极片和电池
本申请要求于2021年11月18日提交中国专利局、申请号为202111372459.0、申请名称为“极片和电池”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请涉及电池技术领域，尤其涉及一种极片和电池。
背景技术
锂离子电池具有容量大、体积小、重量轻和绿色环保等优点，已广泛应用于数码电子产品和电动汽车等行业中。
相关技术中，极片可以包括极片本体和极耳，极耳焊接在极片本体上。
然而，现有的极耳的内阻较大，导致电池的过流性能较差。
发明内容
鉴于上述问题，本申请实施例提供一种极片和电池，能够降低极耳的内阻，提升电池的过流性能。
为了实现上述目的，本申请实施例提供如下技术方案：
本申请实施例的第一方面提供一种极片，包括：极片本体和极耳，部分极耳与部分极片本体相互叠设，且极耳和极片本体在叠设位置相互电性连接；
极耳包括连接的第一延伸段和第二延伸段，至少部分第一延伸段位于叠设位置，第二延伸段在极片本体所在的平面上的投影，与极片本体互不重叠；
第一延伸段的厚度小于第二延伸段的厚度。
通过设置极片本体和极耳，极耳将极片本体与外部的电路进行电性连接。部分极耳与部分极片本体相互叠设且焊接，且极耳和极片本体在叠设位置相互电性连接。极耳包括连接的第一延伸段和第二延伸段，至少部分第一延伸段位于叠设位置，第一延伸段用于与极片本体电性连接。第二延伸段在极片本体所在的平面上的投影，与极片本体互不重叠，第二延伸段用于与外部的 电路电性连接。在形成电芯时，极片本体，以及与极片本体叠设的部分极耳对电芯的厚度造成影响，即位于叠设位置的第一延伸段对电芯的厚度造成影响。而第二延伸段与极片本体在厚度方向不相重叠，也就与电芯在厚度方向不相重叠，其对电芯的厚度没有影响。因此，通过将第一延伸段的厚度设置成小于第二延伸段的厚度。这样，第一延伸段较薄，可以降低极耳对电芯厚度的影响，保证电池的能量密度。而第二延伸段可以设置得较厚，这样，极耳的整体电阻较小，从而提高了电池的过流能力，进一步提升电池的性能。
在一种可能的实现方式中，第一延伸段和第二延伸段之间设置有转接部，第一延伸段和第二延伸段通过转接部连接，转接部在极片本体所在的平面上的投影，与极片本体互不重叠。
在一种可能的实现方式中，第一延伸段的第一端和第二延伸段的第一端在极耳厚度方向上重叠设置，第一延伸段和第二延伸段的重叠部分形成转接部。
在一种可能的实现方式中，第一延伸段的第一端的端面和第二延伸段的第一端的端面相对设置，且分别与转接部的相对两端连接；
转接部的厚度在第一延伸段至第二延伸段的方向上逐渐增大。
在一种可能的实现方式中，转接部的外表面为弧面，弧面朝转接部的厚度方向的中心弯曲；
弧面弯曲的角度为圆角，圆角的半径范围为0.1mm-2mm。
在一种可能的实现方式中，极片本体包括：集流体和活性物质层，集流体包括相对设置的两个功能表面，活性物质层分别设置在两个功能表面上；
极片本体的其中一个功能表面的活性物质层具有凹槽，凹槽的槽底壁为集流体的功能表面；
凹槽在集流体上的投影，位于集流体的背离凹槽一侧的活性物质层在集流体的投影内
极耳与凹槽中的集流体焊接并形成焊印，至少部分焊印位于极耳的背离集流体一侧的面上，且朝向背离集流体的一侧凸起形成第一凸起。
在一种可能的实现方式中，沿集流体的厚度方向，焊印贯穿极耳，且焊印位于集流体的厚度方向上靠近极耳的部分区域内；
或，沿集流体的厚度方向，焊印贯穿极耳和集流体，位于集流体的远离 极耳一侧的焊印朝向背离极耳的一侧凸起形成第二凸起，集流体的背离凹槽一侧的活性物质层覆盖第二凸起；
或，焊印包括外缘部和中间部，外缘部环设在中间部的外侧；
沿集流体的厚度方向，中间部贯穿极耳，且中间部位于集流体的厚度方向上靠近极耳的部分区域内；
沿集流体的厚度方向，外缘部贯穿极耳和集流体，位于集流体的远离极耳一侧的外缘部朝向背离极耳的一侧凸起形成第二凸起，集流体的背离凹槽一侧的活性物质层覆盖第二凸起。
在一种可能的实现方式中，极耳的远离集流体一侧的面上覆盖有保护层，且保护层完全覆盖凹槽；
和/或，凹槽的槽深范围为0.01mm-0.2mm；
和/或，凹槽沿极片的宽度方向的长度范围为1mm-40mm；
和/或，凹槽沿极片的长度方向的长度范围为1mm-30mm；
和/或，焊印的中心至焊印的外边缘之间的距离范围为0.05mm-2.5mm；
和/或，第一凸起的凸起高度为小于等于0.1mm。
在一种可能的实现方式中，第一延伸段的宽度，与第二延伸段的宽度相等；
或，第一延伸段的宽度，大于第二延伸段的宽度。
在一种可能的实现方式中，极耳的宽度从第一延伸段至第二延伸段的方向上逐渐减小。
在一种可能的实现方式中，极耳的形状为梯形或三角形。
在一种可能的实现方式中，极片本体的边缘设置有缺口，缺口位于凹槽的边缘；
至少部分转接部位于缺口中。
在一种可能的实现方式中，第一延伸段的厚度范围为0.005mm-0.1mm；
和/或，第一延伸段的宽度范围为1mm-30mm；
和/或，第一延伸段的长度范围为5mm-30mm；
和/或，第二延伸段的厚度范围为0.01mm-0.5mm；
和/或，第二延伸段的宽度范围为1mm-20mm；
和/或，第二延伸段的长度范围为2mm-20mm。
在一种可能的实现方式中，转接部的长度范围为0.1mm-10mm；
和/或，转接部的宽度范围为1mm-20mm。
在一种可能的实现方式中，还包括辅助胶层，极耳插装在辅助胶层中，辅助胶层在极片本体所在的平面上的投影，与极片本体互不重叠；
辅助胶层的厚度范围为0.1mm-3mm；
和/或，辅助胶层的宽度范围为2mm-40mm；
和/或，辅助胶层的长度范围为2mm-40mm。
本申请实施例的第二方面提供一种电池，包括上述第一方面中的极片。
通过设置极片本体和极耳，极耳将极片本体与外部的电路进行电性连接。部分极耳与部分极片本体相互叠设且焊接，且极耳和极片本体在叠设位置相互电性连接。极耳包括连接的第一延伸段和第二延伸段，至少部分第一延伸段位于叠设位置，第一延伸段用于与极片本体电性连接。第二延伸段在极片本体所在的平面上的投影，与极片本体互不重叠，第二延伸段用于与外部的电路电性连接。在形成电芯时，极片本体，以及与极片本体叠设的部分极耳对电芯的厚度造成影响，即位于叠设位置的第一延伸段对电芯的厚度造成影响。而第二延伸段与极片本体在厚度方向不相重叠，也就与电芯在厚度方向不相重叠，其对电芯的厚度没有影响。因此，通过将第一延伸段的厚度设置成小于第二延伸段的厚度。这样，第一延伸段较薄，可以降低极耳对电芯厚度的影响，保证电池的能量密度。而第二延伸段可以设置得较厚，这样，极耳的整体电阻较小，从而提高了电池的过流能力，进一步提升电池的性能。
本申请的构造以及它的其他发明目的及有益效果将会通过结合附图而对优选实施例的描述而更加明显易懂。
附图说明
为了更清楚地说明本申请实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作以简单地介绍，显而易见地，下面描述中的附图是本申请的一些实施例，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，还可以根据这些附图获得其他的附图。
图1为本申请实施例提供的一种极片的剖视图；
图2为本申请实施例提供的一种极片的俯视图；
图3为本申请实施例提供的一种极耳的正视图；
图4为图3的俯视结图；
图5为本申请实施例提供的另一种极耳的正视图；
图6为图5的俯视图；
图7为本申请实施例提供的一种极耳的俯视图；
图8为本申请实施例提供的另一种极耳的俯视图；
图9为本申请实施例提供的辅助胶层位于转接部的靠近第一延伸段一侧的俯视图；
图10为本申请实施例提供的辅助胶层位于转接部的远离第一延伸段一侧的俯视图；
图11为本申请实施例提供的转接部位于缺口中的俯视图；
图12为本申请实施例提供的转接部位于缺口外的俯视图；
图13为本申请实施例提供的保护层与辅助胶层部分重叠的俯视图。
附图标记说明：
100-极片；
10-极片本体；
11-集流体；
12-活性物质层；
121-凹槽；
13-缺口；
20-极耳；
21-第一延伸段；
22-第二延伸段；
23-转接部；
30-焊接区；
40-保护层；
50-辅助胶层。
具体实施方式
相关技术中，极片可以包括极片本体和极耳，极耳焊接在极片本体上。 极片用于形成电池的电芯，如果极耳的厚度较大则会增加电芯的厚度，从而导致电芯的能量密度较低。为了避免极耳过厚导致电芯的能量密度较低，可以将极耳设置得较薄，这样，极耳对电芯的厚度影响较小。然而，极耳较薄时，极耳的电阻较大，极耳在通电时产生热量较多，极耳的过流能力较差，也会对电池的性能造成影响。
针对上述技术问题，本申请实施例提供了一种极片和电池，通过设置极片本体和极耳，极耳将极片本体与外部的电路进行电性连接。部分极耳与部分极片本体相互叠设且焊接，且极耳和极片本体在叠设位置相互电性连接。极耳包括连接的第一延伸段和第二延伸段，至少部分第一延伸段位于叠设位置，第一延伸段用于与极片本体电性连接。第二延伸段在极片本体所在的平面上的投影，与极片本体互不重叠，第二延伸段用于与外部的电路电性连接。在形成电芯时，极片本体，以及与极片本体叠设的部分极耳对电芯的厚度造成影响，即位于叠设位置的第一延伸段对电芯的厚度造成影响。而第二延伸段与极片本体在厚度方向不相重叠，也就与电芯在厚度方向不相重叠，其对电芯的厚度没有影响。因此，通过将第一延伸段的厚度设置成小于第二延伸段的厚度。这样，第一延伸段较薄，可以降低极耳对电芯厚度的影响，保证电池的能量密度。而第二延伸段可以设置得较厚，这样，极耳的整体电阻较小，从而提高了电池的过流能力，进一步提升电池的性能。
为使本申请实施例的目的、技术方案和优点更加清楚，下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例是本申请一部分实施例，而不是全部的实施例。基于本申请中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
本申请实施例提供一种电池，该电池包括电芯，电芯指安装在电池内部的含有正、负极的电化学电芯。电芯一般不会直接使用，可以通过将电芯安装在电池壳体内部后形成用于充/放电的电池。由于电芯为电池中的蓄电部分，因此电芯的质量直接决定了电池的质量。
电芯可以包括第一极片、隔膜和第二极片，隔膜位于相邻的第一极片和第二极片之间，隔膜用于将第一极片和第二极片电性绝缘。
具体的，第一极片和第二极片中的一个可以是负极片；第一极片和第二 极片中的另一个可以是正极片。
一些示例中，电芯可以为卷绕式的电芯。其中，第一极片和第二极片均为一个，依次叠设的第一极片、隔膜和第二极片绕卷绕中心卷绕，并形成卷绕结构。
另一些示例中，电芯可以为叠片式的电芯。其中，第一极片为多个，第二极片为多个，多个第一极片和多个第二极片沿同一方向依次交错层叠设置，且每相邻的第一极片和第二极片之间设置有隔膜，以使第一极片和第二极片之间电性绝缘。
以下将结合附图对本申请实施例提供的极片100进行详细的说明。
如图1所示，本申请实施例提供一种极片100，该极片100可以用于上述实施例中的电池，该极片100可以是上述实施例的第一极片，也可以是上述实施例的第二极片。
如图1和图2所示，该极片100包括极片本体10和极耳20，极耳20用于将极片本体10与外部的电路进行电性连接。部分极耳20与部分极片本体10相互叠设，以便于极耳20与极片本体10之间通过叠设位置电性相连。
极耳20的材质可以为铜、镍、铝或其他复合金属材料等，本实施例对此不做限制。
如图3和图4所示，极耳20可以包括连接的第一延伸段21和第二延伸段22，至少部分第一延伸段21位于叠设位置，第一延伸段21用于与极片本体10电性连接。其中，第一延伸段21可以部分位于叠设位置，或者，第一延伸段21也可以全部位于叠设位置，本实施例对此不做限制。
第二延伸段22在极片本体10所在的平面上的投影，与极片本体10互不重叠。这样，极片100在形成电芯后，第二延伸段22与电芯在厚度方向不相重叠，第二延伸段22将不会影响电芯的厚度，对电池的能量密度不造成影响。极片本体10通过第一延伸段21和第二延伸段22后与外部的电路电性连接。
第一延伸段21和第二延伸段22的材质可相同，也可以不同。
如图3所示，第一延伸段21的厚度为H1,第二延伸段22的厚度为H2,其中，H1小于H2。通过将第一延伸段21的厚度H1设置成小于第二延伸段22的厚度H2。这样，第一延伸段21较薄，可以降低极耳20对电芯厚度的影响，保证电池的能量密度。而第二延伸段22可以设置得较厚，极耳20的整 体电阻较小，从而提高了极耳的过流能力，以提升电池的性能。
如图3所示，第一延伸段21的厚度H1的范围可以为0.005mm-0.1mm。例如，第一延伸段21的厚度H1可以为0.005mm、0.01mm、0.03mm、0.05mm、0.07mm或0.1mm等。从而可以避免第一延伸段21太薄，第一延伸段21的强度较低。又能够避免第一延伸段21太厚，对电芯的厚度造成影响。
如图4所示，第一延伸段21的宽度为W1，第一延伸段21的宽度W1的范围可以为1mm-30mm。例如，第一延伸段21的宽度W1可以为1mm、5mm、15mm、20mm、25mm或30mm等。从而可以避免第一延伸段21过窄，第一延伸段21与极片本体10之间的连接面积较小，第一延伸段21与极片本体10之间的连接强度较低。又能避免第一延伸段21过宽，占用电池较多的内部空间。
如图4所示，第一延伸段21的长度为L1，第一延伸段21的长度L1的范围可以为5mm-30mm。例如，第一延伸段21的长度L1可以为5mm、15mm、20mm、25mm或30mm等。其原理与第一延伸段21的宽度W1类似，不再赘述。
如图3所示，第二延伸段22的厚度H2的范围可以为0.01mm-0.5mm。例如，第二延伸段22的厚度H2可以为0.01mm、0.05mm、0.1mm、0.2mm、0.3mm或0.5mm等。从而可以避免第二延伸段22太薄，其电阻较大，过流能力较差。又能避免第二延伸段22过厚，占用电池较多的内部空间。
如图4所示，第二延伸段22的宽度为W2，第二延伸段22的宽度W2的范围可以为1mm-20mm。例如，第二延伸段22的宽度W2可以为1mm、5mm、15mm或20mm。从而可以避免第二延伸段22较窄，其电阻较大，过流能力较差。又能避免第二延伸段22过宽，占用电池较多的内部空间。
如图4所示，第二延伸段22的长度为L2，第二延伸段22的长度L2的范围可以为2mm-20mm。例如，第二延伸段22的长度L2可以为2mm、5mm、15mm或20mm。从而可以避免第二延伸段22的长度L2过短，能够与外部的电路连接的面积较小，导致与外部的电路之间连接强度较低。又能避免第二延伸段22的长度L2过长，占用电池较多的内部空间。
一些实施例中，如图3和图4所示，第一延伸段21和第二延伸段22之间设置有转接部23，转接部23为图3中虚线方框中所示。第一延伸段21和第二延伸段22通过转接部23连接，转接部23为第一延伸段21和第二延伸段22的过渡区域。其中，转接部23在极片本体10所在的平面上的投影，与 极片本体10互不重叠，这样，极片100在形成电芯后，转接部23与电芯在厚度方向不相重叠，转接部23将不会影响电芯的厚度，不会导致电芯不平整。
一些示例中，如图3所示，第一延伸段21的第一端和第二延伸段22的第一端在极耳20厚度方向上重叠设置。其中，第一延伸段21的第一端为靠近第二延伸段22的一端，第二延伸段22的第一端为靠近第一延伸段21的一端。第一延伸段21和第二延伸段22的重叠部分形成转接部23。转接部23用于将第一延伸段21和第二延伸段22连接在一起，由于转接部23使得第一延伸段21和第二延伸段22的接触面积较大，第一延伸段21和第二延伸段22之间的连接强度较高。第一延伸段21和第二延伸段22可以通过一体成型、铆接、超声焊接、电阻焊接或者激光焊接等连接。
如图4所示，当第一延伸段21和第二延伸段22之间通过焊接连接时，转接部23上形成的焊印可以为多个，多个焊印间隔设置。单个的焊印较小，使得每个焊印所需输入的能量较小，避免了热量过大导致的第一延伸段21或第二延伸段22过焊或焊穿的现象，保证了极耳20的性能。
第一延伸段21的宽度W1可以大于等于第二延伸段22的宽度W2。其中，当第一延伸段21的宽度W1等于第二延伸段22的宽度W2时，极耳20较为美观。当第一延伸段21的宽度W1大于第二延伸段22的宽度W2，第一延伸段21与极片本体10之间的接触面积较大，可以增加第一延伸段21与极片本体10之间的连接强度。
如图5和图6所示，另一些示例中，第一延伸段21的第一端的端面和第二延伸段22的第一端的端面相对设置。其中，第一延伸段21的第一端为靠近第二延伸段22的一端，第二延伸段22的第一端为靠近第一延伸段21的一端。第一延伸段21的第一端与转接部23的一端连接，第二延伸段22的第一端与转接部23的相对的另一端连接。第一延伸段21和第二延伸段22在厚度方向不相重叠，转接部23可以设置的较薄，转接部23占用电池的内部空间较小。第一延伸段21和第二延伸段22可以通过一体成型、超声焊接、电阻焊接或者激光焊接等连接。
例如，第一延伸段21和第二延伸段22通过一体成型连接。第一延伸段21、转接部23和第二延伸段22之间可以一体成型，可以通过在较厚的极耳20上辊压其中一端形成第一延伸段21，另一端直接形成第二延伸段22，两 者之间的过渡区域形成转接部23，工艺较为简单。
通过一体成型得到的极耳20中，第一延伸段21、转接部23和第二延伸段22之间的连接强度较高。由于第一延伸段21通过辊压形成，第一延伸段21在辊压后变薄变宽，第一延伸段21的宽度W1将大于第二延伸段22的宽度W2。第一延伸段21面积变大后，与极片本体10之间的接触面积增大，可以增加第一延伸段21与极片本体10之间的连接强度。当然的，也可以将第一延伸段21裁切，以使第一延伸段21的宽度W1与第二延伸段22的宽度W2相同，使得极耳20整体较为美观，本实施例对此不做限制。
一些实施例中，如图7和图8所示，极耳20的宽度从第一延伸段21至第二延伸段22的方向上逐渐减小。这样，在极耳20的长度方向上，第一延伸段21和第二延伸段22之间平缓过渡，极耳20上受到的应力较为分散。例如，极耳20的形状可以为三角形、梯形或其他形状，本实施例对此不做限制。
如图5所示，转接部23的厚度在第一延伸段21至第二延伸段22的方向上逐渐增大。这样，在极耳20的厚度方向上，第一延伸段21和第二延伸段22之间过渡较为平缓，可以避免在转接部23应力较为集中。
示例性的，转接部23的沿厚度方向间隔设置的两个外表面可以为弧面，弧面朝转接部23的厚度方向的中心弯曲。这样，转接部23各个位置受力较为均匀，进一步避免转接部23的应力集中。弧面弯曲的角度可以为圆角，圆角的半径范围可以为0.1mm-2mm。例如，圆角的半径可以为0.1mm、0.3mm、0.5mm、1mm、1.5mm或2mm等。从而可以避免圆角半径过小，会导致弧面弯曲程度较大，无法形成平缓的过渡。又能避免圆角半径过大，导致转接部23过长，占用体积较大，对电池内部的其他结构布局造成影响。
如图4所示，一些实施例中，转接部23的长度为L3，转接部23的长度L3的范围可以为0.1mm-10mm。例如，转接部23的长度L3可以为0.1mm、1mm、3mm、5mm或10mm等。从而可以避免转接部23过短，第一延伸段21和第二延伸段22之间的连接强度较低。又能避免转接部23过长，对电池内部的其他结构布局造成影响。
如图4所示，转接部23的宽度为W3，转接部23的宽度W3的范围可以为1mm-20mm。例如，转接部23的宽度W3可以为1mm、5mm、10mm、15mm或20mm等。其原理与转接部23的长度L3类似，不再赘述。
如图1和2所示，一些实施例中，极片本体10包括集流体11和活性物质层12，该极片100可以是负极片或正极片，具体可以根据对集流体11以及各个活性物质层12的材料的具体选择而确定。例如，当集流体11为铝箔、活性物质层12的材料为三元材料或磷酸铁锂等正极活性材料时，极片100为正极片；当集流体11为铜箔、活性物质层12的材料为石墨、硅基等负极活性材料时，极片100为负极片。
其中，集流体11包括相对设置的两个功能表面，活性物质层12分别设置在两个功能表面上。集流体11的功能表面是指用于涂覆活性物质层12的集流体11中最大且相对的两个表面。本申请极片100中的活性物质层12可以仅涂覆于集流体11的一个功能表面，或者同时涂覆在集流体11的两个功能表面。
如图9和图10所示，其中一个功能表面的活性物质层12设有凹槽121，凹槽121暴露集流体11的部分功能表面。凹槽121可以通过清洗将活性物质层12对应部分去除，以露出集流体11而形成。由于凹槽121处的活性物质层12被去除，可以降低电芯的厚度。清洗方式可以为激光清洗、机械清洗或者发泡胶清洗等方式，本申请对清洗方式不做限制。
如图1和图9所示，极耳20与凹槽121中暴露的功能表面电性连接。至少部分第一延伸段21位于凹槽121中。例如，可以是部分第一延伸段21位于凹槽121中，或者，也可以是全部第一延伸段21均位于凹槽121中。极耳20远离集流体11的一侧表面上覆盖有保护层40，保护层40完全覆盖凹槽121。保护层40可以避免极耳20与集流体11形成的焊接毛刺刺穿隔膜而导致电池中相邻的正负极片之间短路。另外，保护层40对极耳20具有固定作用，进一步将极耳20固定在极片100上。
可以实现的是，凹槽121可以靠近极片100的宽度方向的边缘，且凹槽121的靠近该边缘的一侧为敞口。即凹槽121靠近该边缘的外侧没有活性物质层12，凹槽121远离该边缘的外侧设置有活性物质层12。沿极片100的宽度方向，凹槽121的长度小于集流体11的长度。
极耳20与集流体11之间可以通过激光焊接连接，其中，激光焊接可以从极耳20背离集流体11一侧照射到极耳20上进行焊接，极耳20与凹槽121中的集流体11焊接并形成焊印，至少部分焊印位于极耳20的背离集流体11 一侧的面上，且朝向背离集流体11的一侧凸起形成第一凸起。
可以实现的是，第一凸起的凸起的高度为小于等于0.1mm。例如，第一凸起的凸起高度可以0.01mm、0.03mm、0.05mm、0.07mm、0.09mm或0.1mm等，本实施例对此不做限制。从而可以避免第一凸起过高，容易在电池中刺破与之相邻的隔膜，导致电池的正负极短路。
其中，焊印可以有多个，多个焊印间隔设置且共同形成焊接区30。形成单个焊印所输入的能量较小，可以降低对焊接区30附近的活性物质层12的影响。
在每个焊印中，焊印中心至焊印外边缘之间的距离范围可以为0.05mm-2.5mm。例如，该距离可以为0.05mm、0.25mm、0.5mm、1mm、1.5mm或2.5mm等，本实施例对此不做限制。从而可以避免焊印过小，焊印处的极耳20与极片本体10之间接触面积过小，无法形成有效的焊接拉力，焊接强度较低。又能避免焊印过大，形成焊印所输入的能量较高，对焊接区30处的活性物质层12造成影响。
另外，凹槽121在集流体11上的投影，位于集流体11的背离凹槽121一侧的活性物质层12在集流体11的投影内。即凹槽121背面的活性物质层12未被去除，集流体11的暴露面积较小，极片100的活性较高。
一些实施例中，凹槽121的深度范围为0.01mm-0.2mm。例如，凹槽121的深度可以为0.01mm、0.03mm、0.04mm、0.05mm、0.07mm、0.1mm或0.2mm。从而可以避免活性物质层12过薄，电池的能量密度较低。又能避免活性物质层12过厚，靠近集流体11表面的活性物质层12不能得到利用，活性物质层12中的活性物质利用率较低。
凹槽121沿极片100的宽度方向的长度范围可以为1mm-40mm。例如该长度可以为1mm、2mm、5mm、10mm、15mm、20mm、30mm或40mm等。从而可以避免该长度过小，导致极耳20与集流体11之间的可连接的面积较小。又能避免该长度过大，活性物质层12去除较多，对电池的能量密度造成较大影响。
凹槽121沿极片100的长度方向的长度范围可以为1mm-30mm。例如该长度可以为1mm、2mm、5mm、10mm、15mm、20mm、25mm或30mm等。其原理与沿宽度方向的长度值类似，不再赘述。
一些示例中，在设置有凹槽121的极片100中，沿集流体11的厚度方向， 焊印贯穿极耳20，且焊印位于集流体11的厚度方向上靠近极耳20的部分区域内。此时，焊印形成在极耳20背离集流体11的一侧，而集流体11的背离极耳20一侧的面没有形成焊印，集流体11的背离极耳20一侧的面为平面。这样，焊印对集流体11背离极耳20一侧的活性物质层12影响较小。
另一些示例中，在设置有凹槽121的极片100中，沿集流体11的厚度方向，焊印贯穿极耳20和集流体11。此时，在极耳20背离集流体11一侧的面上，以及集流体11背离极耳20一侧的面上均能够观察到焊印。其中，位于集流体11背离极耳20一侧的焊印朝向背离极耳20的一侧凸起，从而形成第二凸起。集流体11的背离凹槽121一侧的活性物质层12覆盖第二凸起，能够减小焊印对该侧的隔膜的影响。
其他一些示例中，在设置有凹槽121的极片100中，在一个焊印中，焊印中的部分贯穿极耳20和集流体11；焊印中的另一部分贯穿极耳20且位于集流体11的厚度方向上靠近极耳20的部分区域内。例如，焊印包括外缘部和中间部，外缘部环设在中间部的外侧。沿集流体11的厚度方向，外缘部贯穿极耳20和集流体11，位于集流体11背离极耳20一侧的外缘部朝向背离极耳20的一侧凸起。此时，在集流体11背离极耳20一侧的面上能够观察到焊印的外缘部。位于集流体11背离极耳20一侧的外缘部朝向背离极耳20的一侧凸起，从而形成第二凸起。其中，集流体11的背离凹槽121一侧的活性物质层12覆盖第二凸起，能够减小外缘部对该侧的隔膜的影响。
沿集流体11的厚度方向，中间部贯穿极耳20，且中间部位于集流体11的厚度方向上靠近极耳20的部分区域内。此时，在集流体11背离极耳20一侧的面上无法观察到中间部。
如图11和图12，极片本体10的边缘设置有缺口13，缺口13为图11中虚线方框中所示。缺口13位于凹槽121的边缘，且缺口13沿厚度方向贯穿极片本体10，即缺口13处的集流体11和活性物质层12均被去除。缺口13处形成了容置空间，至少部分转接部23位于缺口13中，以使转接部23位于缺口13形成的容置空间中。这样，在形成电芯后，缺口13中的转接部23将位于电芯内部，电芯对该部分转接部23具有保护作用。
另外，由于容置空间的存在，使得缺口13处的转接部23不会对电芯的厚度造成影响。例如，转接部23可以部分的位于缺口13中，以对部分 转接部23形成保护。或者，转接部23可以完全位于缺口13中，以对整个转接部23均形成保护，本实施例对此不做限制。
一些实施例中，如图5和图13所示，极片100上还可以设置有辅助胶层50，部分极耳20插装在辅助胶层50中。其中，电芯的外部可以包裹塑封壳，以使电芯与外部绝缘。辅助胶层50可以用于密封(采用热熔密封)极耳20与塑封壳之间的间隙。
一些示例中，辅助胶层50在极片本体10所在的平面上的投影，与极片本体10互不重叠。这样，极片100在形成电芯后，辅助胶层50与电芯在厚度方向不相重叠，辅助胶层50将不会影响电芯的厚度。
如图13所示，辅助胶层50与保护层40在极片100的厚度方向可以具有部分重叠，这样，辅助胶层50与保护层40之间没有极耳20漏出，可以对两者之间的极耳20起到保护作用。或者，如图2所示，辅助胶层50与保护层40也可以具有部分间隙，这样，辅助胶层50的设置位置更加自由。
一些实施例中，如图5所示，辅助胶层50可以位于转接部23的背离第一延伸段21的一侧，即位于第二延伸段22上。这样，转接部23位于塑封壳外，塑封壳的体积较小。
其他一些示例中，如图3所示，辅助胶层50可以位于转接部23背离第二延伸段22的一侧，即位于第一延伸段21上。这样，可以将转接部23设置在塑封壳中，对转接部23起到保护作用。
另一些示例中，辅助胶层50可以覆盖在至少部分转接部23上。辅助胶层50对覆盖的部分转接部23具有保护作用。例如，辅助胶层50可以覆盖在部分转接部23上，或者，辅助胶层50可以覆盖全部的转接部23。
如图5所示，辅助胶层50的厚度为H4，辅助胶层50的厚度H4的范围为0.1mm-3mm。例如，辅助胶层50的厚度H4可以为0.1mm、1mm、1.5mm、2mm或3mm等。从而可以避免辅助胶层50过薄，容易磨损失效。又能避免辅助胶层50过厚，导致辅助胶层50与塑封壳连接处的平整度较差，对密封性造成影响。
如图6所示，辅助胶层50的宽度为W4，辅助胶层50的宽度W4的范围为2mm-40mm。例如，辅助胶层50的宽度W4可以为2mm、10mm、15mm、20mm、30mm、或40mm等。从而可以避免辅助胶层50的过窄，与塑封壳之间的接触 面积较小，密封性较差。又能避免辅助胶层50的过宽，体积较大，对电池内的其他结构布局造成影响。
如图6所示，辅助胶层50的长度为L4，辅助胶层50的长度L4的范围为2mm-40mm。例如，辅助胶层50的长度L4可以为2mm、10mm、15mm、20mm、30mm、或40mm。其原理与辅助胶层50的宽度W4类似，不再赘述。
需要说明的是，极片100的宽度方向即图2中的Y所示的方向；极片100的长度方向即图2中的X所示的方向。第一延伸段21、第二延伸段22、转接部23、辅助胶层50以及极耳20的长度与极片100的宽度方向一致。第一延伸段21、第二延伸段22、转接部23、辅助胶层50以及极耳20的宽度与极片100的长度方向一致。本申请实施例中的宽度和长度仅是为了描述方便，并不意味对任何尺寸的限制。例如，宽度可能大于、小于或等于长度。
这里需要说明的是，本申请实施例涉及的数值和数值范围为近似值，受制造工艺的影响，可能会存在一定范围的误差，这部分误差本领域技术人员可以认为忽略不计。
最后应说明的是：以上各实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述各实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分或者全部技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。

Claims (16)

  1. 一种极片，其特征在于，包括：极片本体和极耳，部分所述极耳与部分所述极片本体相互叠设，且所述极耳和所述极片本体在叠设位置相互电性连接；
    所述极耳包括连接的第一延伸段和第二延伸段，至少部分所述第一延伸段位于所述叠设位置，所述第二延伸段在所述极片本体所在的平面上的投影，与所述极片本体互不重叠；
    所述第一延伸段的厚度小于所述第二延伸段的厚度。
  2. 根据权利要求1所述的极片，其特征在于，所述第一延伸段和所述第二延伸段之间设置有转接部，所述第一延伸段和所述第二延伸段通过所述转接部连接，所述转接部在所述极片本体所在的平面上的投影，与所述极片本体互不重叠。
  3. 根据权利要求2所述的极片，其特征在于，所述第一延伸段的第一端和所述第二延伸段的第一端在所述极耳厚度方向上重叠设置，所述第一延伸段和所述第二延伸段的重叠部分形成所述转接部。
  4. 根据权利要求2所述的极片，其特征在于，所述第一延伸段的第一端的端面和所述第二延伸段的第一端的端面相对设置，且分别与所述转接部的相对两端连接；
    所述转接部的厚度在所述第一延伸段至所述第二延伸段的方向上逐渐增大。
  5. 根据权利要求4所述的极片，其特征在于，所述转接部的外表面为弧面，所述弧面朝所述转接部的厚度方向的中心弯曲；
    所述弧面弯曲的角度为圆角，所述圆角的半径范围为0.1mm-2mm。
  6. 根据权利要求2-5任一所述的极片，其特征在于，所述极片本体包括：集流体和活性物质层，所述集流体包括相对设置的两个功能表面，所述活性物质层分别设置在两个所述功能表面上；
    所述集流体的其中一个所述功能表面的所述活性物质层具有凹槽，所述凹槽的槽底壁为所述集流体的所述功能表面；
    所述凹槽在所述集流体上的投影，位于所述集流体的背离所述凹槽一侧的所述活性物质层在所述集流体的投影内
    所述极耳与所述凹槽中的所述集流体焊接并形成焊印，至少部分所述焊印位于所述极耳的背离所述集流体一侧的面上，且朝向背离所述集流体的一侧凸起形成第一凸起。
  7. 根据权利要求6所述的极片，其特征在于，沿所述集流体的厚度方向，所述焊印贯穿所述极耳，且所述焊印位于所述集流体的厚度方向上靠近所述极耳的部分区域内；
    或，沿所述集流体的厚度方向，所述焊印贯穿所述极耳和所述集流体，位于所述集流体的远离所述极耳一侧的所述焊印朝向背离所述极耳的一侧凸起形成第二凸起，所述集流体的背离所述凹槽一侧的所述活性物质层覆盖所述第二凸起；
    或，所述焊印包括外缘部和中间部，所述外缘部环设在所述中间部的外侧；沿所述集流体的厚度方向，所述中间部贯穿所述极耳，且所述中间部位于所述集流体的厚度方向上靠近所述极耳的部分区域内；沿所述集流体的厚度方向，所述外缘部贯穿所述极耳和所述集流体，位于所述集流体的远离所述极耳一侧的所述外缘部朝向背离所述极耳的一侧凸起形成第二凸起，所述集流体的背离所述凹槽一侧的所述活性物质层覆盖所述第二凸起。
  8. 根据权利要求6所述的极片，其特征在于，所述极耳的远离所述集流体一侧的面上覆盖有保护层，且所述保护层完全覆盖所述凹槽；
    和/或，所述凹槽的槽深范围为0.01mm-0.2mm；
    和/或，所述凹槽沿所述极片的宽度方向的长度范围为1mm-40mm；
    和/或，所述凹槽沿所述极片的长度方向的长度范围为1mm-30mm；
    和/或，所述焊印的中心至所述焊印的外边缘之间的距离范围为0.05mm-2.5mm；
    和/或，所述第一凸起的凸起高度为小于等于0.1mm。
  9. 根据权利要求1-5任一所述的极片，其特征在于，所述第一延伸段的宽度，与所述第二延伸段的宽度相等；
    或，所述第一延伸段的宽度，大于所述第二延伸段的宽度。
  10. 根据权利要求1-5任一所述的极片，其特征在于，所述极耳的宽度从所述第一延伸段至所述第二延伸段的方向上逐渐减小。
  11. 根据权利要求10所述的极片，其特征在于，所述极耳的形状为梯形 或三角形。
  12. 根据权利要求6所述的极片，其特征在于，所述极片本体的边缘设置有缺口，所述缺口位于所述凹槽的边缘；
    至少部分所述转接部位于所述缺口中。
  13. 根据权利要求1-5任一所述的极片，其特征在于，所述第一延伸段的厚度范围为0.005mm-0.1mm；
    和/或，所述第一延伸段的宽度范围为1mm-30mm；
    和/或，所述第一延伸段的长度范围为5mm-30mm；
    和/或，所述第二延伸段的厚度范围为0.01mm-0.5mm；
    和/或，所述第二延伸段的宽度范围为1mm-20mm；
    和/或，所述第二延伸段的长度范围为2mm-20mm。
  14. 根据权利要求2-5任一所述的极片，其特征在于，所述转接部的长度范围为0.1mm-10mm；
    和/或，所述转接部的宽度范围为1mm-20mm。
  15. 根据权利要求1-5任一所述的极片，其特征在于，还包括辅助胶层，所述极耳插装在所述辅助胶层中，所述辅助胶层在所述极片本体所在的平面上的投影，与所述极片本体互不重叠；
    所述辅助胶层的厚度范围为0.1mm-3mm；
    和/或，所述辅助胶层的宽度范围为2mm-40mm；
    和/或，所述辅助胶层的长度范围为2mm-40mm。
  16. 一种电池，其特征在于，包括上述权利要求1-15中任一项所述的极片。
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