CN114122400B - Negative electrode plate and lithium ion battery containing same - Google Patents

Negative electrode plate and lithium ion battery containing same Download PDF

Info

Publication number
CN114122400B
CN114122400B CN202111296240.7A CN202111296240A CN114122400B CN 114122400 B CN114122400 B CN 114122400B CN 202111296240 A CN202111296240 A CN 202111296240A CN 114122400 B CN114122400 B CN 114122400B
Authority
CN
China
Prior art keywords
negative electrode
polyethylene glycol
silane
active material
derivatives
Prior art date
Legal status (The legal status 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 status listed.)
Active
Application number
CN202111296240.7A
Other languages
Chinese (zh)
Other versions
CN114122400A (en
Inventor
唐伟超
李素丽
赵伟
莫肇华
张赵帅
董德锐
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhuhai Cosmx Battery Co Ltd
Original Assignee
Zhuhai Cosmx Battery Co Ltd
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 Zhuhai Cosmx Battery Co Ltd filed Critical Zhuhai Cosmx Battery Co Ltd
Priority to CN202111296240.7A priority Critical patent/CN114122400B/en
Publication of CN114122400A publication Critical patent/CN114122400A/en
Application granted granted Critical
Publication of CN114122400B publication Critical patent/CN114122400B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • 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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • 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

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Secondary Cells (AREA)

Abstract

The invention discloses a negative electrode plate and a lithium ion battery containing the same, wherein the negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer coated on one side or two side surfaces of the negative electrode current collector, and the negative electrode active material layer comprises a negative electrode active material, a conductive agent, a binder and an additive; wherein the additive comprises silane modified polyethylene glycol. The additive can form a film on the surface of the anode active material, can effectively improve the composition of a solid electrolyte film on the surface of the anode/anode active material, improve the lithium ion conductivity and the content of high molecular components in the solid electrolyte film, improve the conduction of electrons and lithium ions in the anode piece of the battery, improve the lithium ion dynamics in the anode piece, avoid the increase of the internal resistance of the battery in the circulation process, and improve the circulation life and capacity retention rate.

Description

Negative electrode plate and lithium ion battery containing same
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a negative electrode plate and a lithium ion battery containing the same.
Background
The lithium ion battery is mainly composed of a positive electrode material, a negative electrode material, a diaphragm and electrolyte, wherein the negative electrode material is used as an important material in the lithium ion battery, and the performance of the negative electrode material directly influences the performance of the battery.
The lithium ion negative electrode material mainly comprises graphite, hard carbon, lithium titanate, silicon oxide, tin, lithium metal and the like. In the first charge and discharge process of the anode material, as lithium ions react on the surface of the anode, larger volume change of the anode and generation of an interface film are caused, the generated interface film mainly consists of inorganic and organic, and the composition of the interface film directly influences effective transmission of lithium ions and electrons on the surface of the electrode plate. How to directionally improve the interface film composition and improve the performance of the battery is the key point of industry research.
Disclosure of Invention
In order to overcome the defects of the prior art that the continuous solid interface film is generated and consumed in the charge and discharge process of the negative electrode, the effective transmission capacity of lithium ions and electrons in the electrode plate is reduced, and the like, the invention provides a negative electrode plate and a lithium ion battery comprising the negative electrode plate. The negative electrode plate can effectively improve the composition of the surface and the internal interface film of the negative electrode, form a solid interface film with a stable structure, improve the transmission of lithium ions and electrons and improve the cycle performance of the lithium ion battery.
The invention aims at realizing the following technical scheme:
A negative electrode tab including a negative electrode current collector and a negative electrode active material layer coated on one or both side surfaces of the negative electrode current collector, the negative electrode active material layer including a negative electrode active material, a conductive agent, a binder, and an additive; wherein the additive comprises silane modified polyethylene glycol.
Conventional battery systems have been developed with the progress of battery charging and discharging, particularly in the first charge and discharge process, in which electrochemical reactions of lithium ions exist in the negative electrode, resulting in volume expansion of the negative electrode material, and formation of a solid interface film on the surface of the negative electrode. The invention adopts the polyethylene glycol modified by the silane as the additive, the additive can electrochemically polymerize on the surface of the negative electrode, and a stable solid interface film is formed on the surface of the negative electrode, and the solid interface film has the characteristics of high lithium ion conductivity, high molecular weight, multiple active groups and good stability, can effectively slow down the occurrence of negative electrode interface side reaction, reduce the increase of internal resistance in the battery circulation process, and improve the battery circulation performance.
Wherein the silane-modified polyethylene glycol is selected from at least one of the compounds shown in the following formula 1:
In the formula 1, n is the polymerization degree; r 1 and R 1 'are end-capping groups and at least one of R 1 and R 1' comprises a-SiR 2R3R4 group, R 2、R3、R4 being identical or different and independently of one another selected from organofunctional groups; r and R' are linking groups.
Wherein the number average molecular weight of the silane modified polyethylene glycol is 200-20000.
Wherein the silane-modified polyethylene glycol is selected from at least one of the following compounds: polyethylene glycol trimethoxysilylpropyl ether, silane-polyethylene glycol-diphenylcyclooctyne, silane-polyethylene glycol-silane, mercapto-polyethylene glycol-silane, carboxy-polyethylene glycol-silane, silane polyethylene glycol monomethyl ether, octa-polyethylene glycol-silane, active ester-polyethylene glycol-silane, azide-polyethylene glycol-silane, tetra-arm polyethylene glycol-silane, amino-polyethylene glycol-silane, alkynyl-polyethylene glycol-silane, hydroxy-polyethylene glycol-silane, maleimide-polyethylene glycol-silane.
Wherein the silane may comprise a capping group selected from alkoxy groups.
Wherein the negative electrode active material layer comprises the following components in percentage by mass:
70 to 99 weight percent of negative electrode active material, 0.5 to 16 weight percent of conductive agent, 0.499 to 12 weight percent of binder and 0.001 to 2 weight percent of additive.
Wherein the surface density of the negative electrode plate is 1-18 mg/cm 2.
Wherein the thickness of the negative electrode current collector is 3-12 mu m.
Wherein the thickness of the negative electrode active material layer (thickness after rolling) is 15 μm to 150 μm.
Wherein the negative electrode active material includes at least one of silicon, siOx (0 < x < 2), lithium silicon alloy, artificial graphite, natural graphite, hard carbon, soft carbon, mesophase microspheres, fullerenes, graphene, coke, carbon fibers, boron and derivatives thereof, aluminum and derivatives thereof, magnesium and derivatives thereof, bismuth and derivatives thereof, nickel and derivatives thereof, silver and derivatives thereof, zinc and derivatives thereof, titanium and derivatives thereof, gallium and derivatives thereof, indium and derivatives thereof, tin and derivatives thereof, lithium nitride and copper nitride.
The invention also provides a lithium ion battery, which comprises the negative electrode plate.
The invention has the beneficial effects that:
The invention provides a negative electrode plate and a lithium ion battery containing the same. The negative electrode plate is prepared by dissolving a negative electrode active material, a conductive agent, a binder and an additive comprising silane modified polyethylene glycol in a solvent, uniformly mixing, coating the surface of a negative electrode current collector, and drying. The additive can be fully mixed with the negative electrode active material, the conductive agent and the binder due to the characteristics of small molecular weight, short polymer chain segment and the like, and can fully contact each component in the negative electrode and be immersed in the internal pores of the electrode plate, namely, the additive can form a film on the surface of the negative electrode active material, can effectively improve the composition of a solid electrolyte film on the surface of the negative electrode/negative electrode active material, improve the lithium ion conductivity and the content of high molecular components in the solid electrolyte film, improve the conduction of electrons and lithium ions in the negative electrode plate of the battery, improve the lithium ion dynamics in the negative electrode plate, avoid the increase of the internal resistance of the battery in the circulation process, and improve the circulation life and the capacity retention rate.
Detailed Description
< Negative electrode sheet >
As described above, the present invention provides a negative electrode tab including a negative electrode current collector and a negative electrode active material layer coated on one or both side surfaces of the negative electrode current collector, the negative electrode active material layer including a negative electrode active material, a conductive agent, a binder, and an additive; wherein the additive comprises silane modified polyethylene glycol.
In one embodiment of the present invention, the silane-modified polyethylene glycol is selected from at least one of the compounds represented by the following formula 1:
In the formula 1, n is the polymerization degree; r 1 and R 1 'are end-capping groups and at least one of R 1 and R 1' comprises a-SiR 2R3R4 group, R 2、R3、R4 being identical or different and independently of one another selected from organofunctional groups; r and R' are linking groups.
In one embodiment of the invention, R 2、R3、R4, which are identical or different, are independently selected from H, C 1-6 alkyl, C 1-6 alkoxy.
In one embodiment of the invention, in formula 1, the linking group may or may not be present, and if present, R and R' are organofunctional groups.
In one embodiment of the present invention, the silane-modified polyethylene glycol has a number average molecular weight of 200 to 20000.
In one embodiment of the present invention, the silane-modified polyethylene glycol is selected from at least one of the following compounds: polyethylene glycol trimethoxysilylpropyl ether, silane-polyethylene glycol-diphenylcyclooctyne, silane-polyethylene glycol-silane, mercapto-polyethylene glycol-silane, carboxy-polyethylene glycol-silane, silane polyethylene glycol monomethyl ether, octa-polyethylene glycol-silane, active ester-polyethylene glycol-silane, azide-polyethylene glycol-silane, tetra-arm polyethylene glycol-silane, amino-polyethylene glycol-silane, alkynyl-polyethylene glycol-silane, hydroxy-polyethylene glycol-silane, maleimide-polyethylene glycol-silane.
In one aspect of the invention, the silane may include a capping group selected from alkoxy groups; in particular, the alkoxy group may be, for example, methoxy, ethoxy or propoxy.
In the present invention, the silane-modified polyethylene glycol may be prepared by methods conventional in the art, or may be commercially available.
In one embodiment of the present invention, the negative electrode active material layer includes the following components in percentage by mass:
70 to 99 weight percent of negative electrode active material, 0.5 to 16 weight percent of conductive agent, 0.499 to 12 weight percent of binder and 0.001 to 2 weight percent of additive.
Illustratively, the negative electrode active material is 70wt％、73wt％、75wt％、76wt％、77wt％、78wt％、79wt％、80wt％、81wt％、82wt％、83wt％、84wt％、85wt％、86wt％、87wt％、88wt％、89wt％、90wt％、91wt％、92wt％、93wt％、94wt％、95wt％、96wt％、97wt％、98wt％、98.5wt％ or 99wt%.
Illustratively, the conductive agent is present in a mass percent of 0.5wt%, 0.8wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, or 16wt%.
Illustratively, the binder is 0.499wt%, 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt% or 12wt%.
Illustratively, the additive is present in a mass percent amount of 0.001wt％、0.05wt％、0.1wt％、0.15wt％、0.25wt％、0.55wt％、0.65wt％、0.70wt％、0.75wt％、0.85wt％、0.90wt％、1.0wt％、1.2wt％、1.5wt％ or 2wt%. When the content of the additive is more than 2wt%, the content of the additive is too high, which can cause the excessive content of the additive in the interface film on the surface of the anode/anode active material, and simultaneously cause the too thick interface film on the surface of the anode/anode active material, so as to increase the internal resistance of the battery, thereby reducing the capacity of the pole piece, deteriorating the lithium conducting network of the pole piece, increasing the lithium loss in the pole piece, reducing the capacity of the battery and affecting the performance of the battery; when the content of the additive is less than 0.001wt%, the content of the additive is too low, the content of the generated interface film is insufficient, and the structure of the formed solid interface film on the surface of the negative electrode/negative electrode active material is unstable, thereby degrading the battery performance.
In one scheme of the invention, the surface density of the negative electrode plate is 1-18 mg/cm 2.
In one embodiment of the invention, the negative electrode current collector has a thickness of 3 μm to 12 μm, preferably 4 μm to 10 μm, such as 3 μm, 4 μm, 5 μm, 8 μm, 10 μm or 12 μm.
According to the present invention, the thickness (thickness after rolling) of the anode active material layer is 15 μm to 150 μm, preferably 30 μm to 100 μm, such as 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm or 150 μm.
In one embodiment of the present invention, the negative electrode active material includes at least one of silicon, siOx (0 < x < 2), lithium silicon alloy, artificial graphite, natural graphite, hard carbon, soft carbon, mesophase microspheres, fullerenes, graphene, coke, carbon fiber, boron and derivatives thereof (such as boron powder, boron oxide), aluminum and derivatives thereof (such as aluminum powder, lithium aluminum alloy), magnesium and derivatives thereof (such as magnesium, magnesium aluminum alloy), bismuth and derivatives thereof (such as bismuth, lithium bismuth alloy), nickel and derivatives thereof (such as nickel, lithium nickel alloy, lithium nitride), silver and derivatives thereof (such as silver powder, lithium silver alloy), zinc and derivatives thereof (such as zinc powder, zinc lithium alloy, zinc nitride), titanium and derivatives thereof (such as titanium powder, lithium titanate, titanium dioxide, lithium titanium alloy, etc.), gallium and derivatives thereof (such as gallium, lithium gallium alloy), indium and derivatives thereof (such as indium powder, lithium indium alloy), tin and derivatives thereof (such as tin powder, stannous oxide, tin sulfate, lithium nitride, copper nitride, etc.
In one aspect of the present invention, the conductive agent includes at least one of conductive carbon black, ketjen black, conductive fiber, conductive polymer, acetylene black, carbon nanotube, graphene, crystalline graphite, conductive oxide, and metal particles.
In one aspect of the present invention, the binder includes at least one of polyvinylidene fluoride and its copolymer derivatives, polytetrafluoroethylene and its copolymer derivatives, polyacrylic acid and its copolymer derivatives, polyvinyl alcohol and its copolymer derivatives, polybutene-styrene rubber and its copolymer derivatives, polyimide and its copolymer derivatives, polyethylenimine and its copolymer derivatives, polyacrylate and its copolymer derivatives, sodium carboxymethyl cellulose and its copolymer derivatives.
< Preparation method of negative electrode sheet >
The invention also provides a preparation method of the negative electrode plate, which comprises the following steps:
uniformly mixing a solvent, a negative electrode active material, a conductive agent, a binder and an additive to prepare a negative electrode slurry; and coating the negative electrode slurry on the surface of a negative electrode current collector, and drying to obtain the negative electrode plate.
In one embodiment of the present invention, the negative electrode slurry contains 100 to 300 parts by mass of a solvent, 70 to 99 parts by mass of a negative electrode active material, 0.5 to 16 parts by mass of a conductive agent, 0.001 to 2 parts by mass of an additive, and 0.499 to 12 parts by mass of a binder.
In one embodiment of the present invention, the solvent is at least one selected from the group consisting of water, acetonitrile, benzene, toluene, xylene, acetone, tetrahydrofuran, hydrofluoroether, and N-methylpyrrolidone.
In one aspect of the invention, the negative electrode slurry is preferably sieved, for example, through a 200 mesh sieve.
In one embodiment of the present invention, the temperature of the drying treatment is 80 to 115 ℃, and the time of the drying treatment is 6 to 36 hours.
< Lithium ion Battery >
The invention also provides a lithium ion battery, which comprises the negative electrode plate.
The present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are illustrative only and are not to be construed as limiting the scope of the invention. All techniques implemented based on the above description of the invention are intended to be included within the scope of the invention.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; the reagents, materials, etc. used in the examples described below are commercially available unless otherwise specified.
Example 1
1) Preparing a positive electrode plate:
96g of positive electrode active material nickel cobalt manganese ternary material (NCM 811), 1.5g of binder polyvinylidene fluoride (PVDF), 1.5g of conductive carbon black and 1g of conductive carbon nano tube are mixed, 150g of N-methylpyrrolidone (NMP) is added, and stirring is carried out under the action of a vacuum stirrer until the mixed system becomes positive electrode slurry with uniform fluidity; uniformly coating the anode slurry on an aluminum foil with the thickness of 13 mu m; drying at 100 ℃ for 36 hours, vacuumizing to obtain a pole piece, rolling and cutting the pole piece to obtain a positive pole piece;
2) Preparing a negative electrode plate:
Preparing slurry from 70g of silicon oxide, 6g of conductive agent single-walled carbon nano tube (SWCNT), 10g of conductive agent conductive carbon black (SP), 2g of polyethylene glycol trimethoxy silicon propyl ether, 6g of adhesive sodium carboxymethyl cellulose (CMC), 6g of adhesive Styrene Butadiene Rubber (SBR) and 300g of deionized water by a wet process, coating the slurry on the surface of a negative current collector copper foil, and drying, rolling and die cutting to obtain a negative electrode plate;
3) Preparation of electrolyte:
uniformly mixing ethylene carbonate, propylene carbonate, diethyl carbonate and n-propyl propionate according to the mass ratio of 40:10:10:40 in a glove box filled with qualified argon water oxygen content, then rapidly adding 1.08mol/L of fully dried lithium hexafluorophosphate (LiPF 6) into the mixture, and uniformly stirring to prepare an electrolyte;
4) Preparation of a lithium ion battery:
And preparing a lithium ion battery cell by the obtained positive pole piece, the negative pole piece and the diaphragm, and obtaining the lithium ion battery after liquid injection packaging and welding.
Comparative example 1.1
Specific procedure of comparative example 1.1 referring to example 1, the main difference is that polyethylene glycol having the same mass and molecular weight as those of polyethylene glycol trimethoxysilylpropyl ether is added to comparative example 1.1, and other conditions are the same as those of example 1.
Comparative example 1.2
Specific procedure of comparative example 1.2 referring to example 1, the main difference is that polyethylene glycol trimethoxy silicone propyl ether was not added in comparative example 1.2, and other conditions were the same as in example 1.
Examples 2 to 6 and other comparative examples
Examples 2-6 and other comparative examples specific procedures refer to example 1, the main differences being the process conditions of the negative electrode sheet, the amounts of the components added, the kinds of the materials of the components, and the specific details are shown in tables 1 and 2.
Table 1 composition of negative electrode sheets of examples and comparative examples
Table 2 composition of negative electrode sheets of examples and comparative examples
Performance tests were performed on the batteries prepared in the above examples and comparative examples:
(1) The method for testing the AC impedance of the internal resistance of the battery comprises the following steps: the 50% SOC lithium ion battery was tested for AC impedance at 25℃using a Metrohm Switzerland PGSTAT302N chemical workstation in the range of 100KHz-0.1mHz, and the test results are shown in Table 3.
Table 3 results of ac impedance test of internal resistance of battery of examples and comparative examples
The internal resistance test result in the battery cycle process shows that: in the cycling process, the internal resistance of the lithium ion battery prepared by the embodiment of the invention is smaller than that of the lithium ion battery prepared by the comparative example. The solid interface film is different from the solid interface film on the surface of the conventional negative electrode/negative electrode active material, has the characteristics of high-speed lithium conduction and the like, and can rapidly conduct lithium ions to pass through, so that the prepared lithium ion battery has lower internal resistance, and meanwhile, the internal resistance increase in the cycling process of the lithium ion battery is smaller, and the solid interface film has a certain application prospect.
(2) The battery cycle performance test method comprises the following steps: the lithium ion battery was subjected to charge-discharge cycle test on a blue battery charge-discharge test cabinet under the test conditions of 25 ℃ and 1C/1C charge-discharge, and the test results are shown in table 4.
Table 4 battery cycle performance test results of examples and comparative examples
The cyclic performance test results of the above examples and comparative examples show that: the capacity retention rate of the lithium ion battery prepared by the embodiment of the invention is higher than that of the lithium ion battery prepared by the comparative example in the cyclic process. The main reason is that the additive added in the invention can form a solid interface film on the surface of the anode/anode active material, and the solid interface film is different from the solid interface film on the surface of the conventional anode/anode active material, and has the characteristics of large molecular weight, high-speed lithium conduction, better stability and the like. The conventional anode/anode active material surface solid interface film is formed on the anode/anode active material surface by consuming electrolyte and lithium salt as lithium ions react during battery cycling. Due to the addition of the additive, the solid interface film with higher stability and higher lithium conducting performance can be formed on the surface of the anode/anode active material, and the performance of the lithium ion battery can be greatly improved.
The results of the cyclic charge and discharge performance tests of the above examples and comparative examples show that: the lithium ion battery negative electrode plate prepared by the method has small internal resistance in the circulation process, and lithium ions have good lithium conducting channels in the negative electrode plate, so that the prepared lithium ion battery has good circulation performance.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. A negative electrode tab including a negative electrode current collector and a negative electrode active material layer coated on one or both side surfaces of the negative electrode current collector, the negative electrode active material layer including a negative electrode active material, a conductive agent, a binder, and an additive; wherein the additive comprises silane modified polyethylene glycol;
The silane modified polyethylene glycol is selected from at least one of the compounds shown in the following formula 1:
in the formula 1, n is the polymerization degree; r 1 and R 1 'are end-capping groups and at least one of R 1 and R 1' comprises a-SiR 2R3R4 group, R 2、R3、R4 being identical or different and independently of one another selected from H, C 1-6 alkyl, C 1-6 alkoxy; and at least one of the groups in R 2、R3、R4 is C 1-6 alkyl or C 1-6 alkoxy; r and R' are linking groups;
the negative electrode active material includes at least one of silicon, siOx,0< x <2, and a silicon alloy;
The mass of the additive accounts for 0.001-2wt% of the total mass of the anode active material layer;
The surface density of the negative electrode plate is 1-18 mg/cm 2;
The silane modified polyethylene glycol is selected from at least one of the following compounds: polyethylene glycol trimethoxysilylpropyl ether, silane-polyethylene glycol-silane, mercapto-polyethylene glycol-silane, carboxyl-polyethylene glycol-silane, silane polyethylene glycol monomethyl ether, octa-polyethylene glycol-silane, azide-polyethylene glycol-silane, tetra-arm polyethylene glycol-silane, amino-polyethylene glycol-silane, alkynyl-polyethylene glycol-silane, hydroxy-polyethylene glycol-silane, maleimide-polyethylene glycol-silane;
the number average molecular weight of the silane modified polyethylene glycol is 200-20000.
2. The negative electrode sheet of claim 1, wherein the silane comprises a capping group selected from alkoxy groups.
3. The negative electrode tab according to claim 1 or 2, wherein the thickness of the negative electrode current collector is 3-12 μm;
And/or the negative electrode active material layer has a thickness of 15 μm to 150 μm.
4. The negative electrode sheet according to claim 1 or 2, wherein the negative electrode active material further comprises at least one of artificial graphite, natural graphite, hard carbon, soft carbon, mesophase microspheres, fullerenes, graphene, coke, carbon fibers, boron and its derivatives, aluminum and its derivatives, magnesium and its derivatives, bismuth and its derivatives, nickel and its derivatives, silver and its derivatives, zinc and its derivatives, titanium and its derivatives, gallium and its derivatives, indium and its derivatives, tin and its derivatives, lithium nitride, copper nitride.
5. A lithium ion battery comprising the negative electrode tab of any one of claims 1-4.
CN202111296240.7A 2021-11-03 2021-11-03 Negative electrode plate and lithium ion battery containing same Active CN114122400B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111296240.7A CN114122400B (en) 2021-11-03 2021-11-03 Negative electrode plate and lithium ion battery containing same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111296240.7A CN114122400B (en) 2021-11-03 2021-11-03 Negative electrode plate and lithium ion battery containing same

Publications (2)

Publication Number Publication Date
CN114122400A CN114122400A (en) 2022-03-01
CN114122400B true CN114122400B (en) 2024-05-28

Family

ID=80380382

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111296240.7A Active CN114122400B (en) 2021-11-03 2021-11-03 Negative electrode plate and lithium ion battery containing same

Country Status (1)

Country Link
CN (1) CN114122400B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115108560B (en) * 2022-06-14 2024-01-30 深圳市德方纳米科技股份有限公司 Silicon oxide and method for regulating and controlling silicon-oxygen ratio in silicon oxide and application thereof
CN115188922A (en) * 2022-06-24 2022-10-14 江苏正力新能电池技术有限公司 Silicon-based negative pole piece, secondary battery containing same and electricity utilization device
CN115651158A (en) * 2022-11-15 2023-01-31 浙江大象新能源科技有限公司 Adhesive for silicon-based negative electrode of lithium battery and preparation method of adhesive

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103413972A (en) * 2013-08-23 2013-11-27 中国科学院广州能源研究所 Alkoxy silane electrolyte material containing oligopolyethylene glycol chain and application of electrolyte material in lithium battery propylene carbonate based electrolyte
CN104066776A (en) * 2012-01-23 2014-09-24 巴斯夫欧洲公司 Composite, its production and its use in separators for electrochemical cells
CN104072533A (en) * 2014-06-10 2014-10-01 中国科学院广州能源研究所 Silicone-nitrile compounds containing low polyoxyethylene units as well as preparation method thereof and application thereof in lithium battery
JP2015018775A (en) * 2013-07-12 2015-01-29 日本電気株式会社 Negative electrode for secondary battery and manufacturing method therefor, and secondary battery using the same
CN109326767A (en) * 2017-07-31 2019-02-12 宁德时代新能源科技股份有限公司 Positive plate, secondary battery and preparation method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050019656A1 (en) * 2002-03-22 2005-01-27 Yoon Sang Young Method for fabricating composite electrodes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104066776A (en) * 2012-01-23 2014-09-24 巴斯夫欧洲公司 Composite, its production and its use in separators for electrochemical cells
JP2015018775A (en) * 2013-07-12 2015-01-29 日本電気株式会社 Negative electrode for secondary battery and manufacturing method therefor, and secondary battery using the same
CN103413972A (en) * 2013-08-23 2013-11-27 中国科学院广州能源研究所 Alkoxy silane electrolyte material containing oligopolyethylene glycol chain and application of electrolyte material in lithium battery propylene carbonate based electrolyte
CN104072533A (en) * 2014-06-10 2014-10-01 中国科学院广州能源研究所 Silicone-nitrile compounds containing low polyoxyethylene units as well as preparation method thereof and application thereof in lithium battery
CN109326767A (en) * 2017-07-31 2019-02-12 宁德时代新能源科技股份有限公司 Positive plate, secondary battery and preparation method thereof

Also Published As

Publication number Publication date
CN114122400A (en) 2022-03-01

Similar Documents

Publication Publication Date Title
CN114122400B (en) Negative electrode plate and lithium ion battery containing same
WO2023093880A1 (en) Lithium-ion battery
CN113707883B (en) Organic coating layer, electrode active material containing organic coating layer and lithium ion battery
WO2023078367A1 (en) Secondary battery
CN114335900A (en) Diaphragm and battery containing same
CN113328098A (en) Negative plate and lithium ion battery comprising same
CN110190258B (en) Silicon-carbon composite material water-based composite slurry, preparation method thereof and lithium ion battery
CN115572557A (en) Binder and battery comprising same
CN116914245A (en) Electrolyte and battery comprising same
CN111384386A (en) Negative electrode active material and preparation method thereof
CN113764673B (en) Electrode paste composition, method of preparing the same, electrode sheet coated with the same, and lithium ion battery including the electrode sheet
WO2022001428A1 (en) Negative pole piece and secondary battery conmprising negative pole piece
KR20170062908A (en) A binder having improved properties for secondary battery and negative electrode for secondary battery comprising the same
CN115295756A (en) Negative plate and battery comprising same
CN114539537B (en) Adhesive for electrode material of lithium ion battery and preparation method thereof
CN117199378B (en) Silicon-based negative electrode material and lithium ion battery
CN114243109B (en) Electrolyte and battery comprising same
CN114024029B (en) Nonaqueous electrolyte and battery comprising same
CN113174208B (en) Binder composition for lithium ion battery and preparation method thereof
CN114188500B (en) Positive electrode plate and lithium ion secondary battery comprising same
US20230369563A1 (en) Negative electrode sheet and lithium-ion battery including same
WO2022194175A1 (en) Secondary battery
CN117673467A (en) Electrolyte and battery comprising same
CN116154303A (en) Electrolyte and battery comprising same
CN114094182A (en) Secondary battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant