CN110970604A - Coated ternary cathode material, and preparation method and application thereof - Google Patents
Coated ternary cathode material, and preparation method and application thereof Download PDFInfo
- Publication number
- CN110970604A CN110970604A CN201811158100.1A CN201811158100A CN110970604A CN 110970604 A CN110970604 A CN 110970604A CN 201811158100 A CN201811158100 A CN 201811158100A CN 110970604 A CN110970604 A CN 110970604A
- Authority
- CN
- China
- Prior art keywords
- cathode material
- ternary cathode
- equal
- residual alkali
- lithium
- 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.)
- Pending
Links
- 239000010406 cathode material Substances 0.000 title claims abstract description 126
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 239000003513 alkali Substances 0.000 claims abstract description 73
- 239000000463 material Substances 0.000 claims abstract description 59
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims abstract description 53
- 238000000576 coating method Methods 0.000 claims abstract description 41
- 239000011248 coating agent Substances 0.000 claims abstract description 40
- 238000000034 method Methods 0.000 claims abstract description 34
- 239000011247 coating layer Substances 0.000 claims abstract description 29
- 150000003482 tantalum compounds Chemical class 0.000 claims abstract description 23
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 22
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 18
- 229910052808 lithium carbonate Inorganic materials 0.000 claims abstract description 18
- 229910052715 tantalum Inorganic materials 0.000 claims abstract description 13
- GUVRBAGPIYLISA-UHFFFAOYSA-N tantalum atom Chemical compound [Ta] GUVRBAGPIYLISA-UHFFFAOYSA-N 0.000 claims abstract description 13
- 238000001354 calcination Methods 0.000 claims description 53
- 238000010438 heat treatment Methods 0.000 claims description 51
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 41
- 238000002156 mixing Methods 0.000 claims description 37
- YRGLXIVYESZPLQ-UHFFFAOYSA-I tantalum pentafluoride Chemical compound F[Ta](F)(F)(F)F YRGLXIVYESZPLQ-UHFFFAOYSA-I 0.000 claims description 35
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 25
- 239000001301 oxygen Substances 0.000 claims description 25
- 229910052760 oxygen Inorganic materials 0.000 claims description 25
- 238000001816 cooling Methods 0.000 claims description 23
- 239000007774 positive electrode material Substances 0.000 claims description 20
- 150000001875 compounds Chemical class 0.000 claims description 16
- 239000002243 precursor Substances 0.000 claims description 16
- 229910004546 TaF5 Inorganic materials 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 11
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims description 10
- 239000010416 ion conductor Substances 0.000 claims description 10
- 229910001416 lithium ion Inorganic materials 0.000 claims description 9
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 claims description 8
- 238000004321 preservation Methods 0.000 claims description 8
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 7
- 229910052759 nickel Inorganic materials 0.000 claims description 7
- 229910014642 LiaNi1−x−y−zCoxMnyMzO2 Inorganic materials 0.000 claims description 6
- 229910052738 indium Inorganic materials 0.000 claims description 6
- 229910003002 lithium salt Inorganic materials 0.000 claims description 6
- 229910052721 tungsten Inorganic materials 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 5
- 229910014248 MzO2 Inorganic materials 0.000 claims description 4
- 229910015450 Ni1-x-yCoxMny(OH)2 Inorganic materials 0.000 claims description 4
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 claims description 4
- YBMRDBCBODYGJE-UHFFFAOYSA-N germanium oxide Inorganic materials O=[Ge]=O YBMRDBCBODYGJE-UHFFFAOYSA-N 0.000 claims description 4
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims description 4
- XIXADJRWDQXREU-UHFFFAOYSA-M lithium acetate Chemical compound [Li+].CC([O-])=O XIXADJRWDQXREU-UHFFFAOYSA-M 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 4
- 238000005303 weighing Methods 0.000 claims description 4
- 229910012464 LiTaF6 Inorganic materials 0.000 claims description 3
- 229910004516 TaF6 Inorganic materials 0.000 claims description 3
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims description 3
- 239000000292 calcium oxide Substances 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims description 2
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 claims description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 2
- 229910003437 indium oxide Inorganic materials 0.000 claims description 2
- 159000000002 lithium salts Chemical class 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 229910000476 molybdenum oxide Inorganic materials 0.000 claims description 2
- QGLKJKCYBOYXKC-UHFFFAOYSA-N nonaoxidotritungsten Chemical compound O=[W]1(=O)O[W](=O)(=O)O[W](=O)(=O)O1 QGLKJKCYBOYXKC-UHFFFAOYSA-N 0.000 claims description 2
- PVADDRMAFCOOPC-UHFFFAOYSA-N oxogermanium Chemical compound [Ge]=O PVADDRMAFCOOPC-UHFFFAOYSA-N 0.000 claims description 2
- PQQKPALAQIIWST-UHFFFAOYSA-N oxomolybdenum Chemical compound [Mo]=O PQQKPALAQIIWST-UHFFFAOYSA-N 0.000 claims description 2
- 229910001930 tungsten oxide Inorganic materials 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims 1
- 239000002994 raw material Substances 0.000 abstract description 6
- 230000000052 comparative effect Effects 0.000 description 20
- 238000005406 washing Methods 0.000 description 11
- 239000004814 polyurethane Substances 0.000 description 9
- 229920002635 polyurethane Polymers 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- 230000004048 modification Effects 0.000 description 7
- 238000012986 modification Methods 0.000 description 7
- 230000015572 biosynthetic process Effects 0.000 description 6
- 239000007789 gas Substances 0.000 description 6
- RSNHXDVSISOZOB-UHFFFAOYSA-N lithium nickel Chemical compound [Li].[Ni] RSNHXDVSISOZOB-UHFFFAOYSA-N 0.000 description 6
- 239000010405 anode material Substances 0.000 description 5
- 101150004907 litaf gene Proteins 0.000 description 4
- 230000005012 migration Effects 0.000 description 3
- 238000013508 migration Methods 0.000 description 3
- 238000010532 solid phase synthesis reaction Methods 0.000 description 3
- 238000003786 synthesis reaction Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- 238000003917 TEM image Methods 0.000 description 2
- 239000011149 active material Substances 0.000 description 2
- 239000011575 calcium Substances 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- -1 tantalum fluoride Chemical class 0.000 description 2
- 229910001460 tantalum ion Inorganic materials 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910013872 LiPF Inorganic materials 0.000 description 1
- 229910012463 LiTaO3 Inorganic materials 0.000 description 1
- 101150058243 Lipf gene Proteins 0.000 description 1
- 229910017221 Ni0.8Co0.1Mn0.1O2 Inorganic materials 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000001351 cycling effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009831 deintercalation Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000011534 incubation Methods 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000002715 modification method Methods 0.000 description 1
- JKQOBWVOAYFWKG-UHFFFAOYSA-N molybdenum trioxide Inorganic materials O=[Mo](=O)=O JKQOBWVOAYFWKG-UHFFFAOYSA-N 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
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
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- 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
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
- H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
-
- 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
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
- H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
- H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
-
- 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
- H01M4/624—Electric conductive fillers
-
- 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
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- 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
- H01M2004/028—Positive 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
Abstract
The invention discloses a coated ternary cathode material, a preparation method and application thereof. The preparation method comprises the steps of coating a ternary material with residual alkali on the surface by using a tantalum compound as a coating raw material, reacting the residual alkali with the tantalum compound to form a coating layer containing lithium and tantalum on the surface of the ternary cathode material, and thus obtaining the coated ternary cathode material, wherein the residual alkali comprises Li2CO3And/or LiOH. Preparation by the inventionThe method can reduce the solubility of residual alkali and materials and improve the electrochemical properties of the materials such as rate capability, cycle performance and the like.
Description
Technical Field
The invention belongs to the field of lithium ion battery anode materials, relates to a ternary anode material, and particularly relates to a coated ternary anode material, and a preparation method and application thereof.
Background
The ternary cathode material has been widely used in the fields of electric vehicles and hybrid electric vehicles due to its advantages of high specific capacity, environmental friendliness, good thermal stability, and the like. However, the bottleneck limiting the application of ternary materials is poor safety due to residual Li on the surface of ternary materials2O is equal to CO in air2And H2O reaction to produce Li2CO3And LiOH, Li2CO3Easily decomposed to generate CO2Gas causes the gas generated by the battery to expand, and potential safety hazard exists.
In order to improve the safety performance and the cycle stability of the ternary material, the residual alkali is usually removed by multiple washing, or the ternary material is modified by doping and cladding, so that the cycle stability of the material is improved, and the generation of gas is reduced. CN108134069A discloses a composite modification method of a cathode material, which comprises the following steps: 1) removing impurities from the precursor of the positive electrode material to obtain a precursor of the positive electrode material after cleaning and removing impurities; 2) mixing the anode material precursor cleaned and decontaminated in the step 1) with a lithium source; 3) sintering to obtain a positive electrode material substrate; 4) dispersing the source substance and the coating auxiliary agent subjected to coating treatment into a solution to be dissolved to obtain a dispersion system, adding the positive electrode material matrix obtained in the step 3) into the dispersion system, stirring, carrying out solid-liquid separation to obtain a coated solid substance, and finally carrying out heat treatment to obtain a material with a coating treatment layer; 5) and (4) washing and drying the material obtained in the step 4) to obtain the composite modified lithium ion battery anode material. The method can prepare the high-nickel cathode material with better stability, and after washing, the structure is kept stable, the residual alkali is effectively reduced, and the performance is not deteriorated. However, the multiple washing inevitably causes a decrease in structural stability while reducing the residual alkali, and the process is complicated and is not suitable for industrial production.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a coated ternary cathode material, a preparation method and application thereof. The invention can realize the purposes of reducing residual alkali, material solubility and lithium-nickel mixed emission by a one-step method, and adopts tantalum fluoride to coat the material, so that the material can react with free lithium on the surface of the material to generate a fast ion conductor compound LiTaF6And the lithium ion migration is facilitated.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the invention provides a coated ternary cathode material, which is characterized in that the coated ternary cathode material comprises a ternary cathode material and a coating layer containing lithium and tantalum coated on the surface of the ternary cathode material.
As a preferable technical scheme of the invention, the ternary cathode material is a high-nickel ternary cathode material.
Preferably, the chemical formula of the ternary cathode material is LiaNi1-x-y-zCoxMnyMzO2Wherein a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, z is more than or equal to 0 and less than or equal to 0.05, and M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W.
In the preferred technical proposal, a is more than or equal to 1.0 and less than or equal to 1.1, for example, 1.0, 1.02, 1.05, 1.08 or 1.1 can be selected; 0.5. ltoreq. x.ltoreq.0.8, for example, 0.5, 0.6, 0.65, 0.7 or 0.8; 0.1. ltoreq. y.ltoreq.0.3, for example, 0.1, 0.15, 0.2, 0.25 or 0.3, etc.; 0. ltoreq. z.ltoreq.0.05, for example, 0, 0.01, 0.02, 0.03 or 0.05, etc., may be used, and 0 means that M is not contained.
Preferably, 1-x-y-z is 0.5 or more.
Preferably, 0.01. ltoreq. z.ltoreq.0.05, and the structural stability of the material can be further improved by doping at this content.
Preferably, the lithium and tantalum containing coating is a fast ion conductor compound coating, preferably LiTaF6Coating or Li2TaF6A coating layer;
preferably, in the coated ternary cathode material, the hydroxyl content is as follows: 0.04 wt% -0.3 wt%, carbonate content is: 0.06 wt% -0.4 wt%.
In a second aspect, the invention provides a preparation method of the coated ternary cathode material, which comprises the following steps:
mixing the ternary cathode material with residual alkali on the surface with a tantalum compound, so that lithium ions (also called free lithium) contained in the residual alkali react with the tantalum compound, and forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material to obtain a coated ternary cathode material;
the residual alkali comprises Li2CO3And/or LiOH.
In the method, because the tantalum compound reacts with the residual alkali, the surface residual alkali of the ternary cathode material can be greatly reduced, and because the tantalum ion radius is similar to that of nickel, the tantalum can replace the position of Ni, so that the lithium-nickel mixed discharge of the nickel-containing ternary cathode material can be reduced.
In a preferred embodiment of the method of the present invention, the tantalum compound is a tantalum compound that can react with residual alkali to form a fast ion conductor compound, preferably tantalum fluoride, and more preferably TaF4And/or TaF5Particularly preferred is TaF5. The preferable technical proposal adopts tantalum fluoride and the like to react with residual alkali to reduce the residual alkali and generate products (such as LiTaF)6Or Li2TaF6) The coated ternary positive electrode material is a fast ion conductor compound, namely the coated ternary positive electrode material coated with the fast ion conductor compound is obtained, so that the residual alkali and lithium-nickel mixed row are reduced, the migration efficiency of lithium ions is improved, and the discharge capacity and the rate capability of the battery are improved.
Preferably, the mixing mode is VC mixing, and the mixing is carried out under the condition of normal temperature.
Preferably, the rotation speed of VC mixing is 600 r/min-800 r/min, such as 600r/min, 650r/min, 700r/min, 725r/min, 750r/min, 780r/min or 800 r/min.
Preferably, the mixing time is 30min to 60min, such as 30min, 35min, 40min, 45min, 50min or 60min and the like.
Preferably, the reaction is carried out under an oxygen atmosphere, which is advantageous in reducing the absorption of moisture and carbon dioxide, reducing the adverse effect on the effect.
As a preferred technical solution of the method of the present invention, the method comprises: placing the ternary cathode material with the surface containing residual alkali and a tantalum compound in a VC machine for VC mixing, then calcining in an oxygen atmosphere, reacting the residual alkali and the tantalum compound, and forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material to obtain the coated ternary cathode material. Wherein the VC machine is a cone mixer.
Preferably, the tantalum compound is contained in an amount of 1 wt% to 5 wt%, for example, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, or the like, based on 100 wt% of the mass of the ternary positive electrode material having a residual alkali on the surface. The control of the mass percentage not only influences the effect of the reaction with the residual alkali, but also directly influences the coating effect of the subsequently obtained coated ternary cathode material, and if the mass percentage is less than 1 wt%, the coating is not uniform; if the mass percentage is more than 5 wt%, the coating layer is too thick, which may result in a decrease in material capacity, which is not favorable for lithium ion deintercalation. Within the preferable range of 1 wt% to 5 wt%, a good effect of reducing residual alkali, and a good coating effect and capacity improvement effect can be achieved.
Preferably, the temperature of the calcination is 500 ℃ to 750 ℃, such as 500 ℃, 525 ℃, 550 ℃, 575 ℃, 600 ℃, 620 ℃, 640 ℃, 655 ℃, 680 ℃, 700 ℃, 725 ℃, or 750 ℃ and the like.
Preferably, the rate of temperature rise to the temperature of calcination is from 2 ℃/min to 5 ℃/min, such as 2 ℃/min, 3 ℃/min, 3.5 ℃/min, 4 ℃/min, or 5 ℃/min, and the like.
Preferably, the calcination is carried out for a holding time of 5h to 10h, such as 5h, 6h, 7h, 8h, 9h, 9.5h or 10h, etc.
Preferably, the method further comprises the step of cooling after calcination is complete, preferably at a rate of 3 ℃/min to 8 ℃/min, such as 3 ℃/min, 4 ℃/min, 5 ℃/min, 6 ℃/min, 7 ℃/min, or 8 ℃/min, and the like.
As a preferable technical scheme of the method, the ternary cathode material with the surface containing residual alkali is prepared by the following method:
(1) in stoichiometric ratio of LiaNi1-x-y-zCoxMnyMzO2Weighing precursor Ni1-x-yCoxMny(OH)2Lithium salt and optional M compound, and then uniformly mixing the materials, wherein M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W, a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, and z is more than or equal to 0 and less than or equal to 0.05.
(2) Calcining the material obtained in the step (1) in an oxygen atmosphere to obtain a ternary cathode material Li with the surface containing residual alkaliaNi1-x-y-zCoxMnyMzO2。
Preferably, in step (1), 1-x-y-z is 0.5 or more.
Preferably, in step (1), z is 0.01. ltoreq. z.ltoreq.0.05, for example, 0.01, 0.02, 0.03, 0.04, 0.05 or the like may be mentioned.
Preferably, the lithium salt in step (1) includes any one of lithium carbonate, lithium hydroxide, lithium nitrate or lithium acetate or a combination of at least two thereof.
Preferably, the M compound of step (1) has a particle size of 20nm to 80nm, such as 20nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, or the like.
Preferably, the M compound in step (1) is M oxide, preferably including any one or a combination of at least two of calcium oxide, germanium oxide, indium oxide, molybdenum oxide, barium oxide or tungsten oxide.
Preferably, the mixing of step (1) is carried out in a three-dimensional mixer.
Preferably, the calcination of step (2) is: firstly, the heat preservation calcination is carried out at the first temperature of 300-500 ℃, and then the heat preservation calcination is carried out when the temperature is raised to the second temperature. The first temperature is, for example, 300 ℃, 350 ℃, 375 ℃, 400 ℃, 430 ℃, 460 ℃, 480 ℃, or 500 ℃ or the like.
Preferably, the rate of heating to the first temperature is 2 ℃/min-8 ℃/min, such as 2 ℃/min, 3 ℃/min, 4 ℃/min, 5 ℃/min, 6 ℃/min, or 8 ℃/min, and the like.
Preferably, the incubation calcination at the first temperature is for a time in the range of 1h to 3h, such as 1h, 1.5h, 2h, 2.5h, or 3h, and the like.
Preferably, the second temperature is 810 ℃ to 900 ℃, such as 810 ℃, 820 ℃, 835 ℃, 850 ℃, 860 ℃, 870 ℃, 880 ℃ or 900 ℃ and the like.
Preferably, the holding calcination time at the second temperature is 10h to 15h, such as 10h, 11.5h, 13h, 14h, 14.5h, 15h, or the like.
Preferably, the method further comprises a step of cooling after the calcination in step (2) is completed, preferably at a rate of 5 ℃/min to 10 ℃/min, such as 5 ℃/min, 6 ℃/min, 7 ℃/min, 8 ℃/min, 9 ℃/min, 10 ℃/min, or the like.
As a further preferred technical solution of the method of the present invention, the method comprises the steps of:
(1) in stoichiometric ratio of LiaNi1-x-y-zCoxMnyMzO2Weighing precursor Ni1-x-yCoxMny(OH)2Lithium salt and M oxide with the particle size of 20nm-80nm, and then uniformly mixing the materials In a three-dimensional mixer, wherein M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W, a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, and z is more than or equal to 0.01 and less than or equal to 0.05.
(2) Calcining the material obtained in the step (1) in an oxygen atmosphere, and cooling at the speed of 5-10 ℃/min after calcining to obtain the ternary cathode material Li with the surface containing residual alkaliaNi1-x-y-zCoxMnyMzO2；
The calcination is as follows: firstly heating to 300-500 ℃ at the speed of 2-8 ℃/min, keeping the temperature and calcining for 1-3 h, and then heating to 810-900 ℃ and keeping the temperature and calcining for 10-15 h;
(3) mixing a ternary positive electrode material with residual alkali on the surface and TaF5According to 100Placing the materials in a VC machine according to the mass ratio of (1-5) for VC mixing, then heating to 500-750 ℃ at the speed of 2-5 ℃/min in an oxygen atmosphere, carrying out heat preservation and calcination for 5-10 h, reacting residual alkali with a tantalum compound, forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material, and cooling at the speed of 3-8 ℃/min after calcination is finished, thus obtaining the coated ternary cathode material.
In a third aspect, the invention provides a lithium ion battery comprising the coated ternary cathode material of the second aspect.
Compared with the prior art, the invention has the following beneficial effects:
(1) the ternary cathode material is coated by taking the tantalum compound as the raw material, the tantalum compound reacts with residual alkali on the surface of the ternary cathode material in the coating process, the solubility of the residual alkali on the surface and the material is reduced, the radius of the tantalum ion is similar to that of nickel, and the tantalum can replace the position of Ni, so that the lithium-nickel mixed discharge of the nickel-containing ternary cathode material can be reduced. The formation of the coating layer can also reduce the direct contact between the ternary cathode material and the electrolyte, and inhibit the occurrence of side reactions on the surface of the material. The combined action of the factors improves the cycling stability and the rate capability of the material, reduces the generation of gas and improves the safety performance.
By selecting a tantalum compound which reacts with residual alkali to form a fast ion conductor compound, such as tantalum fluoride, as a coating material, the fast ion conductor compound (such as LiTaF) can be formed while reducing the solubility of residual alkali and material and reducing the lithium-nickel mixed row6) The coating layer improves the lithium ion migration effect and improves the electrochemical performance.
(2) According to the method, the tantalum compound is used for coating the ternary cathode material which is not washed, so that residual alkali on the surface of the material can be remarkably reduced, and compared with the ternary cathode material which is not coated, OH of the ternary cathode material is-Reduce CO by over 45.5 percent3 2-The reduction by more than 42.0 percent, the problems of structural damage of ternary materials and the like caused by repeated washing and residual alkali removal in the prior art are solved, and the problem that the performance of the materials is reduced by coating residual alkali in the materials by conventional coating in the prior art is also solved.
(3) The coated ternary cathode material is synthesized in one step by dry coating, the problems of gas generation, unstable cycle and low rate capacity of the cathode material are solved, the process is simple, the operation is convenient, no special requirement is required on the experimental environment, the processing performance is good, the large-scale industrial production is facilitated, and the method has a good application prospect.
Drawings
FIGS. 1a and 1b are SEM images of a coated ternary cathode material obtained in example 1 and an uncoated sample obtained in comparative example 1, respectively;
fig. 2 is a TEM image of the coated ternary cathode material obtained in example 1.
Detailed Description
The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.
Example 1:
preparation of ternary cathode Material Li1.01Ni0.5Co0.2Mn0.25Ge0.05O2Then using TaF5The method for coating the ternary material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.01Ni0.5Co0.2Mn0.25Ge0.05O218.66g of lithium carbonate, 22.7g of lithium hydroxide and 91.61g of Ni were weighed0.5Co0.2Mn0.3(OH)2Precursor, 5.23g GeO2Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 350 ℃ at the speed of 2 ℃/min, preserving heat for 2h, heating to 900 ℃ and preserving heat for 15h, and cooling to room temperature at the speed of 7.5 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and has high surface alkali residue.
Coating modification:
(3) 50g of ternary positive electrode material and 1.5g of tantalum fluoride (TaF) were weighed5) Is placed in VC and mixedMixing in a mixer at normal temperature at 600r/min for 30 min.
(4) Placing the material obtained in the step (3) in a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 550 ℃ at the speed of 2 ℃/min, preserving heat for 7.5 hours, then cooling to room temperature at the speed of 5 ℃/min to obtain a coated ternary cathode material which is composed of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating material tantalum fluoride can react with residual alkali at the root part to form LiTaO3The residual alkali comprises Li2CO3And/or LiOH.
Example 2:
preparation of ternary cathode Material Li1.02Ni0.6Co0.2Mn0.18In0.02O2Then using TaF5The method for coating the ternary cathode material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.02Ni0.6Co0.2Mn0.18In0.02O219.02g of lithium carbonate, 33.96g of lithium acetate and 91.99g of Ni were weighed0.6Co0.2Mn0.2(OH)2Precursor, 2.78g In2O3Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (2) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 500 ℃ at the speed of 8 ℃/min, preserving heat for 1h, heating to 880 ℃ and preserving heat for 10h, cooling to room temperature at the speed of 5 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and the surface of the ternary cathode material contains residual alkali.
Coating modification:
(3) 50g of ternary positive electrode material and 0.5g of tantalum fluoride (TaF) were weighed out5) Mixing in VC mixer at normal temperature at 800r/min for 30 min.
(4) Putting the material obtained in the step (3) into a sagger for heat treatment, and calcining in an oxygen atmosphereHeating to 750 ℃ at a speed of 5 ℃/min, preserving heat for 7.5h, and then cooling to room temperature at a speed of 3 ℃/min to obtain a coated ternary cathode material which is composed of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating layer is formed by reacting tantalum fluoride and residual alkali, and the residual alkali comprises Li2CO3And/or LiOH.
Example 3:
preparation of ternary cathode Material Li1.04Ni0.65Co0.15Mn0.17Ca0.03O2Then using TaF5The method for coating the ternary cathode material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.04Ni0.65Co0.15Mn0.27Ca0.03O223.37g of lithium hydroxide, 35.85g of lithium nitrate and 91.98g of Ni were weighed0.65Co0.15Mn0.2(OH)2The precursor and 1.68g CaO are placed in a three-dimensional mixer, polyurethane balls are added, and the mixture is uniformly mixed.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 400 ℃ at the speed of 5 ℃/min, preserving heat for 3h, heating to 860 ℃ and preserving heat for 12.5h, and cooling to room temperature at the speed of 10 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and the surface of the ternary cathode material contains residual alkali.
Coating modification:
(3) 50g of ternary positive electrode material and 1.0g of tantalum fluoride (TaF) were weighed5) Mixing in VC mixer at normal temperature at 650r/min for 40 min.
(4) Putting the material obtained in the step (3) into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 700 ℃ at the speed of 3.5 ℃/min, preserving heat for 5 hours, then cooling to room temperature at the speed of 5.5 ℃/min to obtain a coated ternary cathode material consisting of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating layer is formed by reaction of tantalum fluoride and residual alkaliForming, said residual alkali comprising Li2CO3And/or LiOH.
Example 4:
preparation of ternary cathode Material Li1.06Ni0.7Co0.15Mn0.125Mo0.025O2Then using TaF5The method for coating the ternary cathode material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.06Ni0.7Co0.15Mn0.125Mo0.025O219.58g of lithium carbonate, 36.54g of lithium nitrate and 92.16g of Ni were weighed0.7Co0.15Mn0.15(OH)2Precursor, 3.6g MoO3Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (2) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 400 ℃ at the speed of 7 ℃/min, preserving heat for 3h, heating to 840 ℃ and preserving heat for 12h, cooling to room temperature at the speed of 6 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and the surface of the ternary cathode material contains residual alkali.
Coating modification:
(3) 50g of ternary positive electrode material and 2.0g of tantalum fluoride (TaF) were weighed5) Mixing in VC mixer at normal temperature at 600r/min for 50 min.
(4) Putting the material obtained in the step (3) into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 625 ℃ at a speed of 4 ℃/min, preserving heat for 7 hours, then cooling to room temperature at a speed of 8 ℃/min to obtain a coated ternary cathode material which is composed of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating layer is formed by reaction of tantalum fluoride and residual alkali, and the residual alkali comprises Li2CO3And/or LiOH.
Example 5:
preparation of ternary cathode Material Li1.08Ni0.8Co0.1Mn0.09W0.01O2Then using TaF5The method for coating the ternary cathode material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.08Ni0.8Co0.1Mn0.09W0.01O248.54g of lithium hydroxide and 92.34gNi g of lithium hydroxide are weighed0.8Co0.1Mn0.1(OH)2Precursor, 2.32g WO3Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 400 ℃ at the speed of 6 ℃/min, preserving heat for 3h, heating to 810 ℃ and preserving heat for 13h, cooling to room temperature at the speed of 9 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and the surface of the ternary cathode material contains residual alkali.
Coating modification:
(3) 50g of ternary positive electrode material and 2.5g of tantalum fluoride (TaF) were weighed5) Mixing in VC mixer at normal temperature at 700r/min for 45 min.
(4) Putting the material obtained in the step (3) into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 500 ℃ at the speed of 5 ℃/min, preserving heat for 10 hours, then cooling to room temperature at the speed of 6 ℃/min to obtain a coated ternary cathode material which is composed of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating layer is formed by reaction of tantalum fluoride and residual alkali, and the residual alkali comprises Li2CO3And/or LiOH.
Example 6:
preparation of ternary cathode Material Li1.1Ni0.8Co0.1Mn0.01O2Then using TaF4The method for coating the ternary cathode material while reducing the residual alkali comprises the following steps:
preparing a ternary cathode material:
(1) in stoichiometric ratio Li1.1Ni0.8Co0.1Mn0.01O246.13g of lithium hydroxide and 92.34gNi g of lithium hydroxide are weighed0.8Co0.1Mn0.1(OH)2And putting the precursor into a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 400 ℃ at the speed of 6 ℃/min, preserving heat for 3h, heating to 810 ℃ and preserving heat for 13h, cooling to room temperature at the speed of 9 ℃/min to obtain the ternary cathode material, wherein the ternary cathode material is not subjected to post-treatment such as washing and the like, and the surface of the ternary cathode material contains residual alkali.
Coating modification:
(3) 50g of ternary positive electrode material and 1.5g of tantalum fluoride (TaF) were weighed4) Mixing in VC mixer at normal temperature at 750r/min for 35 min.
(4) Putting the material obtained in the step (3) into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 500 ℃ at the speed of 5 ℃/min, preserving heat for 10 hours, then cooling to room temperature at the speed of 6 ℃/min to obtain a coated ternary cathode material which is composed of a ternary cathode material and a coating layer coated on the surface of the ternary cathode material, wherein the coating layer is formed by reaction of tantalum fluoride and residual alkali, and the residual alkali comprises Li2CO3And/or LiOH.
Comparative example 1:
using this comparative example 1 in comparison with example 1:
this example used a solid phase method for the synthesis of Li1.01Ni0.5Co0.2Mn0.25Ge0.05O2The material specifically comprises the following steps:
(1) in stoichiometric ratio Li1.01Ni0.5Co0.2Mn0.25Ge0.05O218.66g of lithium carbonate, 22.7g of lithium hydroxide and 91.61g of Ni were weighed0.5Co0.2Mn0.3(OH)2Precursor, 5.23g GeO2Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 350 ℃ at the speed of 2 ℃/min, preserving heat for 2h, heating to 900 ℃ and preserving heat for 15h, and cooling to room temperature at the speed of 7.5 ℃/min to obtain the ternary cathode material.
Comparative example 2:
using this comparative example 2 in comparison with example 2:
this example used a solid phase method for the synthesis of Li1.02Ni0.6Co0.2Mn0.18In0.02O2The material specifically comprises the following steps:
(1) in stoichiometric ratio Li1.02Ni0.65Co0.15Mn0.18In0.02O219.02g of lithium carbonate, 33.96g of lithium acetate and 91.99g of Ni were weighed0.6Co0.2Mn0.18(OH)2Precursor, 2.78g In2O3Placing in a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 500 ℃ at the speed of 8 ℃/min, preserving heat for 1h, heating to 880 ℃ and preserving heat for 10h, and cooling to room temperature at the speed of 5 ℃/min to obtain the ternary cathode material.
Comparative example 3:
using this comparative example 3 in comparison with example 6:
this example used a solid phase method for the synthesis of Li1.1Ni0.8Co0.1Mn0.1O2The material specifically comprises the following steps:
(1) in stoichiometric ratio Li1.1Ni1.1Co0.1Mn0.1O246.13g of lithium hydroxide and 92.34gNi g of lithium hydroxide are weighed0.8Co0.1Mn0.1(OH)2And (3) placing the precursor into a three-dimensional mixer, adding polyurethane balls, and uniformly mixing.
(2) And (3) putting the uniformly mixed materials into a sagger for heat treatment, calcining in an oxygen atmosphere, heating to 400 ℃ at the speed of 6 ℃/min, preserving heat for 3h, heating to 810 ℃ and preserving heat for 13h, and cooling to room temperature at the speed of 9 ℃/min.
And (3) detection:
the positive electrode materials of examples 1 to 6 and comparative examples 1 to 3 were tested by the following methods:
the surface appearance and the particle size of the sample are observed by a scanning electron microscope of Hitachi S4800.
The material was tested for residual alkali using an automatic potentiometric titrator model METTLER TOLEDO G20.
Electrochemical performance tests were performed on the materials synthesized in each example and comparative example, specifically:
the coated ternary positive electrode material obtained in each embodiment and the ternary positive electrode material of the comparative example are used as active materials, the active materials, acetylene black and polyvinylidene fluoride are stirred and mixed according to the mass ratio of 8:1:1, and then a working electrode is prepared by using LiPF containing 1mol/L6The EC-EMC (volume ratio is 3:7) of the battery is electrolyte, the polypropylene porous membrane is a diaphragm, the metal lithium sheet is a counter electrode, and the CR2025 type battery is assembled in an argon glove box. And (4) performing charge and discharge tests, wherein the voltage range is 3.0-4.3V, and the current is 1C.
FIGS. 1a and 1b are SEM images of the coated ternary cathode material obtained in example 1 and the uncoated sample obtained in comparative example 1, respectively, and it can be seen that the coated ternary cathode material obtained after coating using tantalum fluoride as a raw material has a significant coating layer on the surface, which is formed by tantalum fluoride (TaF)5) Formation of fast ion conductor compound LiTaF by free lithium reaction on surface of material6。
FIG. 2 is a TEM image of the coated ternary cathode material obtained in example 1, from which a significant coating is seen, which is obtained by tantalum fluoride (TaF)5) Formation of fast ion conductor compound LiTaF by free lithium reaction on surface of material6。
Table 1 shows the comparison between the coated ternary cathode material obtained after coating with tantalum fluoride as the coating raw material in each example and the residual alkali of each comparative uncoated sample, and the significant decrease in residual alkali after coating with tantalum fluoride is clearly shown by the comparison between example 1 and comparative example 1, example 2 and comparative example 2, and example 6 and comparative example 3.
Table 2 shows electrochemical data of the coated ternary cathode material obtained after coating tantalum fluoride as a coating raw material in each example and comparative uncoated samples, and it is obvious that the cycle performance of the material is more stable after coating tantalum fluoride by comparing example 1 with comparative example 1, example 2 with comparative example 2, and example 6 with comparative example 3.
TABLE 1 residual alkali for coated tantalum fluoride and uncoated samples
TABLE 2 electrochemical Performance data
The embodiment and the comparative example show that a coating layer is formed on the surface of the ternary cathode material while the method reduces the residual alkali and the mixed lithium-nickel row, the coating layer is a product generated by the reaction of the tantalum compound and the free lithium on the surface of the ternary cathode material, the electrochemical performance, particularly the cycle performance, of the obtained coated ternary cathode material is greatly improved, and the problem of safety performance reduction caused by gas generation is solved.
The applicant states that the present invention is illustrated in detail by the above examples, but the present invention is not limited to the above detailed methods, i.e. it is not meant that the present invention must rely on the above detailed methods for its implementation. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.
Claims (10)
1. The coated ternary cathode material is characterized by comprising a ternary cathode material and a coating layer containing lithium and tantalum, wherein the coating layer is coated on the surface of the ternary cathode material.
2. The ternary cathode material according to claim 1, wherein the ternary cathode material is a high nickel ternary cathode material;
preferably, the chemical formula of the ternary cathode material is LiaNi1-x-y-zCoxMnyMzO2Wherein a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, z is more than or equal to 0 and less than or equal to 0.05, and M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W;
preferably, 1-x-y-z is greater than or equal to 0.5;
preferably, 0.01. ltoreq. z.ltoreq.0.05;
preferably, the lithium and tantalum containing coating is a fast ion conductor compound coating, preferably LiTaF6Coating or Li2TaF6A coating layer;
preferably, in the coated ternary cathode material, the hydroxyl content is as follows: 0.04 wt% -0.3 wt%, carbonate content is: 0.06 wt% -0.4 wt%.
3. The preparation method of the coated ternary cathode material according to claim 1 or 2, wherein the preparation method comprises the following steps:
mixing the ternary cathode material with residual alkali on the surface with a tantalum compound, reacting lithium ions contained in the residual alkali with the tantalum compound, and forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material to obtain a coated ternary cathode material;
the residual alkali comprises Li2CO3And/or LiOH.
4. Process according to claim 3, characterized in that said tantalum compound is tantalum fluoride, preferably TaF4And/or TaF5Further preferably TaF5；
Preferably, the mixing mode is VC mixing;
preferably, the rotating speed of VC mixing is 600 r/min-800 r/min;
preferably, the mixing time is 30 min-60 min;
preferably, the reaction is carried out under an oxygen atmosphere.
5. The method for preparing according to claim 3 or 4, characterized in that the method comprises:
placing the ternary cathode material with the surface containing residual alkali and a tantalum compound in a VC machine for VC mixing, then calcining in an oxygen atmosphere, reacting the residual alkali and the tantalum compound, and forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material to obtain the coated ternary cathode material.
6. The method according to claim 5, wherein the tantalum compound is contained in an amount of 1 to 5 wt% based on 100 wt% of the ternary positive electrode material having a residual alkali on the surface;
preferably, the temperature of the calcination is 500 ℃ to 750 ℃;
preferably, the heating rate of heating to the calcining temperature is 2-5 ℃/min;
preferably, the calcination is carried out for a holding time of 5h to 10 h.
7. The method of claim 5 or 6, further comprising a step of cooling after calcination is completed, preferably at a rate of 3 ℃/min to 8 ℃/min.
8. The production method according to any one of claims 3 to 7, wherein the ternary positive electrode material having a residual alkali on the surface is produced by:
(1) in stoichiometric ratio of LiaNi1-x-y-zCoxMnyMzO2Weighing precursor Ni1-x-yCoxMny(OH)2Lithium salt and optional M compound, and then uniformly mixing the materials, wherein M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W, a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, and z is more than or equal to 0 and less than or equal to 0.05;
(2) calcining the material obtained in the step (1) in an oxygen atmosphere to obtain a ternary cathode material Li with the surface containing residual alkaliaNi1-x-y-zCoxMnyMzO2；
Preferably, in step (1), 1-x-y-z is preferably not less than 0.5;
preferably, in step (1), z is 0.01. ltoreq. z.ltoreq.0.05;
preferably, the lithium salt in step (1) comprises any one of lithium carbonate, lithium hydroxide, lithium nitrate or lithium acetate or a combination of at least two thereof;
preferably, the particle size of the M compound in the step (1) is 20nm-80 nm;
preferably, the M compound in step (1) is M oxide, preferably including any one or a combination of at least two of calcium oxide, germanium oxide, indium oxide, molybdenum oxide, barium oxide or tungsten oxide;
preferably, the mixing of step (1) is carried out in a three-dimensional mixer;
preferably, the calcination of step (2) is: firstly, carrying out heat preservation calcination at a first temperature of 300-500 ℃, and then heating to a second temperature for heat preservation calcination;
preferably, the heating rate of heating to the first temperature is 2 ℃/min-8 ℃/min;
preferably, the heat preservation calcination time at the first temperature is 1h-3 h;
preferably, the second temperature is 810 ℃ to 900 ℃;
preferably, the heat preservation calcination time at the second temperature is 10h-15 h;
preferably, the method further comprises the step of cooling after the calcination in step (2) is completed, preferably at a rate of 5 ℃/min to 10 ℃/min.
9. The method according to any one of claims 3 to 8, characterized in that it comprises the following steps:
(1) in stoichiometric ratio of LiaNi1-x-y-zCoxMnyMzO2Weighing precursor Ni1-x-yCoxMny(OH)2Lithium salt and M oxide with the particle size of 20nm-80nm, and then uniformly mixing the materials In a three-dimensional mixer, wherein M comprises any one or the combination of at least two of Ca, Ge, In, Mo, Ba or W, a is more than or equal to 1.0 and less than or equal to 1.1, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.1 and less than or equal to 0.3, and z is more than or equal to 0.01 and less than or equal to 0.05;
(2) calcining the material obtained in the step (1) in an oxygen atmosphere, and cooling at the speed of 5-10 ℃/min after calcining to obtain the ternary cathode material Li with the surface containing residual alkaliaNi1-x-y-zCoxMnyMzO2；
The calcination is as follows: firstly heating to 300-500 ℃ at the speed of 2-8 ℃/min, keeping the temperature and calcining for 1-3 h, and then heating to 810-900 ℃ and keeping the temperature and calcining for 10-15 h;
(3) mixing a ternary positive electrode material with residual alkali on the surface and TaF5Placing the mixture into a VC machine according to the mass ratio of 100 (1-5) for VC mixing, then heating to 500-750 ℃ at the speed of 2-5 ℃/min in an oxygen atmosphere, carrying out heat preservation and calcination for 5-10 h, reacting residual alkali with a tantalum compound, forming a coating layer containing lithium and tantalum on the surface of the ternary cathode material, and cooling at the speed of 3-8 ℃/min after calcination is finished, thus obtaining the coated ternary cathode material.
10. A lithium ion battery comprising the encapsulated ternary cathode material of claim 1 or 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811158100.1A CN110970604A (en) | 2018-09-30 | 2018-09-30 | Coated ternary cathode material, and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811158100.1A CN110970604A (en) | 2018-09-30 | 2018-09-30 | Coated ternary cathode material, and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110970604A true CN110970604A (en) | 2020-04-07 |
Family
ID=70028909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811158100.1A Pending CN110970604A (en) | 2018-09-30 | 2018-09-30 | Coated ternary cathode material, and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110970604A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111453779A (en) * | 2020-04-15 | 2020-07-28 | 蜂巢能源科技有限公司 | Method for reducing residual alkali content on surface of positive electrode material and application thereof |
| CN112151779A (en) * | 2020-09-18 | 2020-12-29 | 深圳市贝特瑞纳米科技有限公司 | Binary anode composite material and preparation method and application thereof |
| CN112670506A (en) * | 2020-12-22 | 2021-04-16 | 北京理工大学重庆创新中心 | Nickel-cobalt-manganese-tantalum composite quaternary positive electrode material coated by fast ion conductor and preparation method thereof |
| CN112786893A (en) * | 2021-02-26 | 2021-05-11 | 宁波容百新能源科技股份有限公司 | Nano zirconium lithium fluoride in-situ coated high-nickel ternary cathode material, preparation method thereof and lithium ion battery |
| CN114597372A (en) * | 2022-03-18 | 2022-06-07 | 蜂巢能源科技股份有限公司 | Ultrahigh nickel cathode material and preparation method and application thereof |
| CN114864947A (en) * | 2022-06-21 | 2022-08-05 | 远东电池江苏有限公司 | Lithium supplementing method for coated high-nickel ternary cathode material |
| CN115536080A (en) * | 2022-11-29 | 2022-12-30 | 瑞浦兰钧能源股份有限公司 | High-nickel positive electrode material and preparation method and application thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1711214A (en) * | 2002-11-12 | 2005-12-21 | 三菱化学株式会社 | Method for producing fluorine-containing lithium compound |
| CN101156260A (en) * | 2005-04-15 | 2008-04-02 | 能原材公司 | Cathode active material coated with fluorine compound for lithium secondary batteries and method for preparing the same |
| CN102832389A (en) * | 2012-09-25 | 2012-12-19 | 湖南长远锂科有限公司 | High-nickel positive active material of surface-modified lithium ion battery and preparation method of positive active material |
| CN102893431A (en) * | 2010-05-17 | 2013-01-23 | 住友电气工业株式会社 | Positive electrode body for nonaqueous electrolyte battery, method for producing same, and nonaqueous electrolyte battery |
| CN107516731A (en) * | 2017-07-18 | 2017-12-26 | 南京创源天地动力科技有限公司 | Modification lithium-ion battery anode material and preparation method thereof and the electrochemical energy storage device using modification lithium-ion battery anode material |
-
2018
- 2018-09-30 CN CN201811158100.1A patent/CN110970604A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1711214A (en) * | 2002-11-12 | 2005-12-21 | 三菱化学株式会社 | Method for producing fluorine-containing lithium compound |
| CN101156260A (en) * | 2005-04-15 | 2008-04-02 | 能原材公司 | Cathode active material coated with fluorine compound for lithium secondary batteries and method for preparing the same |
| CN102893431A (en) * | 2010-05-17 | 2013-01-23 | 住友电气工业株式会社 | Positive electrode body for nonaqueous electrolyte battery, method for producing same, and nonaqueous electrolyte battery |
| CN102832389A (en) * | 2012-09-25 | 2012-12-19 | 湖南长远锂科有限公司 | High-nickel positive active material of surface-modified lithium ion battery and preparation method of positive active material |
| CN107516731A (en) * | 2017-07-18 | 2017-12-26 | 南京创源天地动力科技有限公司 | Modification lithium-ion battery anode material and preparation method thereof and the electrochemical energy storage device using modification lithium-ion battery anode material |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111453779A (en) * | 2020-04-15 | 2020-07-28 | 蜂巢能源科技有限公司 | Method for reducing residual alkali content on surface of positive electrode material and application thereof |
| CN112151779A (en) * | 2020-09-18 | 2020-12-29 | 深圳市贝特瑞纳米科技有限公司 | Binary anode composite material and preparation method and application thereof |
| CN112670506A (en) * | 2020-12-22 | 2021-04-16 | 北京理工大学重庆创新中心 | Nickel-cobalt-manganese-tantalum composite quaternary positive electrode material coated by fast ion conductor and preparation method thereof |
| CN112670506B (en) * | 2020-12-22 | 2022-04-19 | 北京理工大学重庆创新中心 | Nickel-cobalt-manganese-tantalum composite quaternary positive electrode material coated by fast ion conductor and preparation method thereof |
| CN112786893A (en) * | 2021-02-26 | 2021-05-11 | 宁波容百新能源科技股份有限公司 | Nano zirconium lithium fluoride in-situ coated high-nickel ternary cathode material, preparation method thereof and lithium ion battery |
| CN112786893B (en) * | 2021-02-26 | 2022-04-22 | 宁波容百新能源科技股份有限公司 | Nano zirconium lithium fluoride in-situ coated high-nickel ternary cathode material, preparation method thereof and lithium ion battery |
| CN114597372A (en) * | 2022-03-18 | 2022-06-07 | 蜂巢能源科技股份有限公司 | Ultrahigh nickel cathode material and preparation method and application thereof |
| CN114864947A (en) * | 2022-06-21 | 2022-08-05 | 远东电池江苏有限公司 | Lithium supplementing method for coated high-nickel ternary cathode material |
| CN115536080A (en) * | 2022-11-29 | 2022-12-30 | 瑞浦兰钧能源股份有限公司 | High-nickel positive electrode material and preparation method and application thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110970604A (en) | Coated ternary cathode material, and preparation method and application thereof | |
| CN107994212B (en) | A kind of layered cathode material of lithium ion battery and preparation method thereof | |
| CN106602015A (en) | Preparation method for fluorine-doped nickel-cobalt-manganese system ternary positive electrode material and prepared material | |
| CN110581259B (en) | Monocrystalline ternary cathode material with good dispersibility, mixed lithium and nickel and low residual alkali, and preparation method and application thereof | |
| CN116504954B (en) | Positive electrode material, preparation method thereof and sodium ion battery | |
| JP2022546936A (en) | Cobalt-free layered positive electrode material, manufacturing method thereof, positive electrode sheet, and lithium ion battery | |
| CN112736233B (en) | Lithium ion battery electrode active material, preparation method thereof, electrode and battery | |
| CN113023794A (en) | Cobalt-free high-nickel cathode material, preparation method thereof, lithium ion battery cathode and lithium ion battery | |
| CN110931741A (en) | Tin sulfide quantum dot loaded titanium carbide composite nano material and preparation method thereof | |
| JP2023143694A (en) | Positive electrode material, battery, and electronic apparatus | |
| CN116314704B (en) | Coated modified sodium ion layered cathode material and preparation method thereof | |
| CN112694104B (en) | Prussian blue analogue, preparation method thereof, negative electrode material and application | |
| CN116314739B (en) | Manganese-based layered oxide positive electrode material and preparation method and application thereof | |
| CN110364708B (en) | Preparation method of manganous manganic oxide-stannic oxide/cobaltosic oxide composite material | |
| CN111564613A (en) | Tin-cobalt @ carbon @ manganous manganic oxide yolk-shell structured lithium ion battery cathode composite material and preparation method thereof | |
| CN116314767A (en) | Prussian blue sodium ion battery anode material and preparation method and application thereof | |
| CN113206250B (en) | Semiconductor cathode material and preparation method thereof | |
| CN115966701A (en) | Metal fluoride modified positive electrode material, preparation method, positive electrode and sodium ion battery | |
| JP4055269B2 (en) | Manganese oxide and method for producing the same, lithium manganese composite oxide using manganese oxide, and method for producing the same | |
| CN113764671A (en) | Anode material of lithium ion battery | |
| CN108117096A (en) | Lithium ion battery negative material and negative electrode of lithium ion battery | |
| CN113443659A (en) | Wet-method doping and carbon-coating co-modified quaternary anode material and preparation method thereof | |
| CN108448075B (en) | Manganese-based composite positive electrode material of lithium ion battery and preparation method thereof | |
| CN110776019A (en) | Synthesis of high-voltage anode material and preparation of high-voltage electrolyte for lithium ion battery | |
| CN115403080B (en) | Single crystal type nickel-cobalt-aluminum-lithium oxide positive electrode material and preparation method thereof |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200407 |