CN117117109B - Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery - Google Patents
Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery Download PDFInfo
- Publication number
- CN117117109B CN117117109B CN202310002203.3A CN202310002203A CN117117109B CN 117117109 B CN117117109 B CN 117117109B CN 202310002203 A CN202310002203 A CN 202310002203A CN 117117109 B CN117117109 B CN 117117109B
- Authority
- CN
- China
- Prior art keywords
- roasting
- cobalt
- positive electrode
- free
- transition metal
- 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
Links
- 239000007774 positive electrode material Substances 0.000 title claims abstract description 48
- 238000002360 preparation method Methods 0.000 title claims abstract description 20
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims abstract description 16
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 16
- 239000000463 material Substances 0.000 claims abstract description 100
- 239000011248 coating agent Substances 0.000 claims abstract description 45
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims abstract description 39
- 229910052744 lithium Inorganic materials 0.000 claims abstract description 39
- 239000002243 precursor Substances 0.000 claims abstract description 39
- 238000002156 mixing Methods 0.000 claims abstract description 38
- 239000002019 doping agent Substances 0.000 claims abstract description 31
- 238000000034 method Methods 0.000 claims abstract description 29
- 239000010405 anode material Substances 0.000 claims abstract description 25
- 230000008569 process Effects 0.000 claims abstract description 11
- 238000004519 manufacturing process Methods 0.000 claims abstract description 9
- 239000002245 particle Substances 0.000 claims description 17
- 238000003756 stirring Methods 0.000 claims description 17
- 238000010438 heat treatment Methods 0.000 claims description 14
- 239000013078 crystal Substances 0.000 claims description 9
- 238000007873 sieving Methods 0.000 claims description 9
- 238000001354 calcination Methods 0.000 claims description 8
- 238000004321 preservation Methods 0.000 claims description 8
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical group [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 5
- 229910052808 lithium carbonate Inorganic materials 0.000 claims description 5
- 230000000630 rising effect Effects 0.000 claims description 5
- 229910010413 TiO 2 Inorganic materials 0.000 claims description 4
- 230000001681 protective effect Effects 0.000 claims description 4
- 238000010304 firing Methods 0.000 claims description 2
- 229910000314 transition metal oxide Inorganic materials 0.000 abstract description 32
- 239000011247 coating layer Substances 0.000 abstract description 13
- 230000002829 reductive effect Effects 0.000 abstract description 9
- 150000001768 cations Chemical class 0.000 abstract description 5
- 229910021645 metal ion Inorganic materials 0.000 abstract description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 34
- 239000011572 manganese Substances 0.000 description 24
- 229910052721 tungsten Inorganic materials 0.000 description 18
- 229910052723 transition metal Inorganic materials 0.000 description 17
- 239000000203 mixture Substances 0.000 description 13
- 239000007789 gas Substances 0.000 description 11
- 238000012360 testing method Methods 0.000 description 11
- 150000003624 transition metals Chemical class 0.000 description 11
- 229910044991 metal oxide Inorganic materials 0.000 description 10
- 150000004706 metal oxides Chemical class 0.000 description 10
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 9
- 230000014759 maintenance of location Effects 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 6
- 230000009286 beneficial effect Effects 0.000 description 6
- 238000012512 characterization method Methods 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 6
- 150000003623 transition metal compounds Chemical group 0.000 description 6
- -1 transition metal sulfide Chemical class 0.000 description 6
- 229910052726 zirconium Inorganic materials 0.000 description 6
- 239000002131 composite material Substances 0.000 description 5
- FXOOEXPVBUPUIL-UHFFFAOYSA-J manganese(2+);nickel(2+);tetrahydroxide Chemical compound [OH-].[OH-].[OH-].[OH-].[Mn+2].[Ni+2] FXOOEXPVBUPUIL-UHFFFAOYSA-J 0.000 description 5
- 230000003044 adaptive effect Effects 0.000 description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- QXYJCZRRLLQGCR-UHFFFAOYSA-N dioxomolybdenum Chemical compound O=[Mo]=O QXYJCZRRLLQGCR-UHFFFAOYSA-N 0.000 description 4
- 229910052759 nickel Inorganic materials 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 230000002195 synergetic effect Effects 0.000 description 4
- 229910017052 cobalt Inorganic materials 0.000 description 3
- 239000010941 cobalt Substances 0.000 description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 3
- 239000011162 core material Substances 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000007599 discharging Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 239000011164 primary particle Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 229910000299 transition metal carbonate Inorganic materials 0.000 description 3
- 229910021561 transition metal fluoride Inorganic materials 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- OIFBSDVPJOWBCH-UHFFFAOYSA-N Diethyl carbonate Chemical compound CCOC(=O)OCC OIFBSDVPJOWBCH-UHFFFAOYSA-N 0.000 description 2
- 229910006404 SnO 2 Inorganic materials 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 239000010406 cathode material Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- IEJIGPNLZYLLBP-UHFFFAOYSA-N dimethyl carbonate Chemical compound COC(=O)OC IEJIGPNLZYLLBP-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011267 electrode slurry Substances 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000011056 performance test Methods 0.000 description 2
- 238000001878 scanning electron micrograph Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 229910013870 LiPF 6 Inorganic materials 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- HFCVPDYCRZVZDF-UHFFFAOYSA-N [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O Chemical compound [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O HFCVPDYCRZVZDF-UHFFFAOYSA-N 0.000 description 1
- 239000006230 acetylene black Substances 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 239000006258 conductive agent Substances 0.000 description 1
- 239000011258 core-shell material Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009831 deintercalation Methods 0.000 description 1
- 230000005347 demagnetization Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 229910021389 graphene Inorganic materials 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000009830 intercalation Methods 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
- 239000010410 layer Substances 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 1
- FRMOHNDAXZZWQI-UHFFFAOYSA-N lithium manganese(2+) nickel(2+) oxygen(2-) Chemical compound [O-2].[Mn+2].[Ni+2].[Li+] FRMOHNDAXZZWQI-UHFFFAOYSA-N 0.000 description 1
- RSNHXDVSISOZOB-UHFFFAOYSA-N lithium nickel Chemical compound [Li].[Ni] RSNHXDVSISOZOB-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 238000005502 peroxidation Methods 0.000 description 1
- 238000006479 redox reaction Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B1/00—Single-crystal growth directly from the solid state
-
- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/16—Oxides
- C30B29/22—Complex oxides
-
- 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
- H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
-
- 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
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Engineering & Computer Science (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Composite Materials (AREA)
- Crystallography & Structural Chemistry (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention provides a cobalt-free monocrystal positive electrode material, a preparation method thereof and a lithium ion battery. The preparation method of the cobalt-free monocrystal anode material comprises the steps of firstly mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material; and mixing the primary roasting material with a coating agent, and roasting to obtain the cobalt-free monocrystal anode material. The step a) of doping the transition metal oxide can be more adaptively doped into the lattice of the positive electrode material, and the transition metal oxide is effectively combined with metal ions in the primary roasting material to form a covalent bond structure, so that cation mixed discharge is inhibited, the compactness of the material is improved, the gas production is reduced, and the cycle performance of the material is effectively improved. Meanwhile, the transition metal oxide coating layer is added through the secondary roasting process of the step b), and the transition metal oxide coating layer and the step a) are cooperated, so that the cycle performance of the cobalt-free positive electrode material is further improved.
Description
Technical Field
The invention relates to the field of lithium ion batteries, in particular to a cobalt-free monocrystal positive electrode material, a preparation method thereof and a lithium ion battery.
Background
With the rapid development of 3C (computer, communication and consumer electronics) and automobiles and other fields in China, the demand for lithium ion batteries is gradually increased, and the lithium ion batteries have the advantages of high energy density, good cycle performance and the like, so that the lithium ion batteries are widely applied, and the positive electrode material is used as a core material of the lithium ion batteries and directly influences the performance of the lithium ion batteries. Common positive electrode materials comprise lithium cobaltate, lithium iron phosphate, lithium manganate, lithium nickelate and the like, and the development prospect is better at present, namely ternary positive electrode materials, such as NCM (Ni xCoyMnz),NCA(NixCoyAlz) and the like, and the ternary materials have the advantages of high density, better cycle life and the like. However, cobalt element is taken as strategic resource, the price of the cobalt element is high for a long time, so the cost of the ternary positive electrode material nickel cobalt lithium manganate (Li (Ni xCoyMn1-x-y)O2) is high, which brings great challenges to the new energy industry and limits the development of the ternary material.
The cobalt-free binary anode material not only gets rid of the restriction of cobalt element, but also has the advantages of higher reversible specific capacity, low price and the like, and is increasingly favored by the energy industry. With the continuous improvement of energy requirements of various industries, increasing the energy density of the positive electrode material becomes a trend, and the most direct method is to increase the content of nickel element, but the increase of the content of nickel can lead to the increase of residual alkali on the surface of the material and the increase of gas production of a battery, so that the safety of the battery is at risk. Meanwhile, the defect of Co element can cause the problems of unstable structure, reduced service life and the like.
CN112186158a discloses a positive electrode composite material, which comprises a cobalt-free positive electrode material and a composite carbon coating layer formed on the surface of the cobalt-free positive electrode material, wherein the particle size of the cobalt-free positive electrode material is 3-5 μm, and the cobalt-free positive electrode material with the particle size in the range is more beneficial to coating of composite carbon. The graphene is selected from the composite carbon, so that the ion conductivity of the cobalt-free positive electrode material can be effectively improved, the positive electrode composite material can also effectively isolate electrolyte, the occurrence of side reaction is reduced, and the first charge and discharge capacity of the material is improved. But the cycle performance of the positive electrode material is poor, and the gas yield is high and the safety is low.
CN111599999a discloses a cobalt-free positive electrode material, a preparation method thereof and a lithium ion battery, wherein the preparation method comprises the following steps: performing first sintering treatment on the lithium source material and the cobalt-free precursor to obtain a sintered product; crushing the sintered product to 1-2 mu m to obtain a cobalt-free monocrystalline material; and performing second sintering treatment on the cobalt-free monocrystalline material, the boron coating agent and the carbon coating agent to obtain the cobalt-free anode material. The cobalt-free positive electrode material prepared by the method has the advantages of stable structure, high capacitance, excellent current multiplying power performance and the like. However, the ion conductivity of the prepared cobalt-free cathode material is reduced, DCR is increased, and the electrical properties of the battery are deteriorated.
The cobalt-free positive electrode material has the problems of high gas yield and serious swelling of the battery during the circulation process, and meanwhile, the potential safety hazard existing in the cobalt-free positive electrode material is exposed, and the product circulation performance is poor.
Disclosure of Invention
In view of the above, the invention provides a cobalt-free monocrystalline cathode material, a preparation method thereof and a lithium ion battery. The cobalt-free monocrystal anode material provided by the invention can effectively improve the cycle performance.
The invention provides a preparation method of a cobalt-free monocrystal anode material, which comprises the following steps:
a) Mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material;
b) Mixing the primary roasting material with a coating agent, and roasting to obtain a cobalt-free monocrystal anode material;
wherein,
In the precursor Ni xMny(OH)2, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.2 and less than or equal to 0.5, and x+y=1;
The dopant is a transition metal oxide; the transition metal in the dopant is at least one of W, mo, zr, ca, ba, si;
The coating agent is a transition metal compound; the transition metal compound is selected from at least one of transition metal oxide, transition metal sulfide, transition metal fluoride, transition metal hydroxide, transition metal carbonate and transition metal acetate; the transition metal in the coating agent is at least one of W, mo, zr, ca, ba, si, ti.
Preferably, the transition metal in the dopant is at least one of W, mo and Zr;
The transition metal in the coating agent is at least one of W, mo, zr and Ti.
Preferably, in step a), the roasting conditions are: air atmosphere, heating rate 1-5 deg.c/min, roasting temperature 800-1000 deg.c and heat maintaining time 8-16 hr.
Preferably, in step b), the roasting conditions are: air atmosphere, heating rate 1-5 deg.c/min, roasting temperature 400-600 deg.c and heat maintaining time 4-8 hr.
Preferably, the molar ratio of the precursor Ni xMny(OH)2 to Li in the lithium source is 1.00:1.00-1.10;
the dosage of the doping agent is 0.05-1wt% of the total mass of the lithium source and the precursor Ni xMny(OH)2;
The dosage of the coating agent is 0.05-1 wt% of the mass of the primary roasting material.
Preferably, in step a), the mixing is stirring mixing;
The stirring and mixing conditions are as follows: the stirring speed is 500-1000 r/min under the protective atmosphere, and the stirring time is 20-50 min.
Preferably, in step a), the lithium source is lithium carbonate and/or lithium hydroxide;
in step b), after calcination, further: sieving and demagnetizing;
the mesh number of the screen used for sieving is 300-400 meshes.
Preferably, the primary roasting material obtained in the step a) has an average particle diameter D50 of 3-10 mu m, a specific surface area of 0.3-0.9 m 2/g and a residual lithium content of less than 0.2wt%.
The invention also provides a cobalt-free monocrystal anode material prepared by the preparation method in the technical scheme.
The invention also provides a lithium ion battery, wherein the positive electrode active material on the positive electrode is the cobalt-free monocrystal positive electrode material in the technical scheme.
The preparation method of the cobalt-free monocrystal anode material comprises the steps of firstly mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material; and mixing the primary roasting material with a coating agent, and roasting to obtain the cobalt-free monocrystal anode material. The step a) of doping transition metal oxides, particularly metal oxides of W, mo and Zr, can be doped into the lattice of the positive electrode material in a more adaptive manner, and effectively combines with metal ions in the primary roasting material to form a covalent bond structure, so that cation mixed discharge is inhibited, the compactness of the material is improved, the gas production is reduced, and the cycle performance of the material is effectively improved. Meanwhile, the secondary roasting process of the step b) is adopted to increase the transition metal oxide coating layer, especially the metal oxide coating layer of W, mo, zr, ti, so that the binding capacity of the primary roasting material and the transition metal oxide coating agent can be improved, compared with the method that the transition metal oxide coating agent is added into a lithium source and a precursor for co-roasting, the applicant has unexpectedly found that the transition metal oxide coating agent can be subjected to secondary roasting at a lower temperature and better coated on the surface of the primary roasting material, thereby being beneficial to the stability of the cobalt-free positive electrode material structure, reducing the gas production amount of the cobalt-free material, and further improving the cycle performance of the cobalt-free positive electrode material by the synergistic effect of the step a).
Test results show that the gram capacity of the positive electrode material obtained by the invention reaches over 184mAh/g after the first discharge under the charging and discharging multiplying power of 0.1C/0.1C in the voltage range of 4.4-3.0V; the capacity retention rate reaches more than 97.5% after the cycle of 50 weeks at normal temperature and 0.5C multiplying power at 25 ℃ under the voltage range of 4.4-3.0V.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.
FIG. 1 is an XRD pattern of the primary calcined material obtained in step a) in example 1;
FIG. 2 is an SEM image of the primary calcined material obtained in step a) of example 1;
FIG. 3 is a graph showing the effect of the normal temperature cycle performance of a battery assembled from the cobalt-free single crystal positive electrode material obtained in example 1;
Fig. 4 is a graph showing the effect of high-temperature cycle performance of the battery assembled from the cobalt-free single crystal positive electrode material obtained in example 1.
Detailed Description
The invention provides a preparation method of a cobalt-free monocrystal anode material, which comprises the following steps:
a) Mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material;
b) Mixing the primary roasting material with a coating agent, and roasting to obtain a cobalt-free monocrystal anode material;
wherein,
In the precursor Ni xMny(OH)2, x is more than or equal to 0.5 and less than or equal to 0.8, y is more than or equal to 0.2 and less than or equal to 0.5, and x+y=1;
The dopant is a transition metal oxide; the transition metal in the dopant is at least one of W, mo, zr, ca, ba, si;
The coating agent is a transition metal compound; the transition metal compound is selected from at least one of transition metal oxide, transition metal sulfide, transition metal fluoride, transition metal hydroxide, transition metal carbonate and transition metal acetate; the transition metal in the coating agent is at least one of W, mo, zr, ca, ba, si, ti.
The preparation method of the cobalt-free monocrystal anode material comprises the steps of firstly mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material; and mixing the primary roasting material with a coating agent, and roasting to obtain the cobalt-free monocrystal anode material. The step a) of doping transition metal oxides, particularly metal oxides of W, mo and Zr, can be doped into the lattice of the positive electrode material in a more adaptive manner, and effectively combines with metal ions in the primary roasting material to form a covalent bond structure, so that cation mixed discharge is inhibited, the compactness of the material is improved, the gas production is reduced, and the cycle performance of the material is effectively improved. Meanwhile, the secondary roasting process of the step b) is adopted to increase the transition metal oxide coating layer, especially the metal oxide coating layer of W, mo, zr, ti, so that the binding capacity of the primary roasting material and the transition metal oxide coating agent can be improved, compared with the method that the transition metal oxide coating agent is added into a lithium source and a precursor for co-roasting, the applicant has unexpectedly found that the transition metal oxide coating agent can be subjected to secondary roasting at a lower temperature and better coated on the surface of the primary roasting material, thereby being beneficial to the stability of the cobalt-free positive electrode material structure, reducing the gas production amount of the cobalt-free material, and further improving the cycle performance of the cobalt-free positive electrode material by the synergistic effect of the step a).
Regarding step a):
a) Mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material.
In the present invention, the lithium source is preferably lithium carbonate and/or lithium hydroxide.
In the invention, in the precursor Ni xMny(OH)2 (nickel manganese hydroxide), x is more than or equal to 0.5 and less than or equal to 0.8, and can be specifically 0.5, 0.6, 0.7 and 0.8; y is more than or equal to 0.2 and less than or equal to 0.5, and can be specifically 0.2, 0.3, 0.4 and 0.5; and x+y=1. According to the method, nickel-manganese hydroxide with proper x and y values is selected, the content of nickel and manganese is controlled, and then a lithium source and a nickel-manganese hydroxide precursor are mixed and baked. The source of the precursor Ni xMny(OH)2 is not particularly limited in the present invention, and may be prepared according to a conventional preparation method well known to those skilled in the art. In some embodiments of the invention, the precursor is Ni 0.55Mn0.45(OH)2 or Ni 0.75Mn0.25(OH)2.
In the invention, the molar ratio of the precursor Ni xMny(OH)2 to Li in the lithium source is preferably 1.00:1.00-1.10, and particularly 1.00∶1.00、1.00∶1.01、1.00∶1.02、1.00∶1.03、1.00∶1.04、1.00∶1.05、1.00∶1.06、1.00∶1.07、1.00∶1.08、1.00∶1.09、1.00∶1.10., the invention is controlled in the above molar ratio range, which is beneficial to improving the gram capacity of the material for the first time.
In the present invention, the dopant is a transition metal oxide. The transition metal in the transition metal oxide is at least one of W, mo, zr, ca, ba, si, more preferably one or more of W, mo and Zr, i.e. the dopant is preferably at least one of WO 3、MoO2 and ZrO 2. According to the research of the applicant, the nickel-manganese hydroxide precursor with certain x and y values is selected, the nickel content is higher, the lithium-nickel mixed discharge is serious in the lithium source roasting process, the cycle performance and the crystal structure stability are affected, the specific transition metal oxide dopant is introduced in the lithium source and precursor roasting process, the mixed discharge can be reduced, and the prepared primary roasting precursor has uniform particle size and dimension and stable structure.
In the invention, the dosage of the doping agent is 0.05wt% -1wt% of the total mass of the lithium source and the precursor Ni xMny(OH)2, and can be specifically 0.05wt％、0.10wt％、0.15wt％、0.20wt％、0.25wt％、0.30wt％、0.35wt％、0.40wt％、0.45wt％、0.50wt％、0.55wt％、0.60wt％、0.65wt％、0.70wt％、0.75wt％、0.80wt％、0.85wt％、0.90wt％、0.95wt％、1.00wt％.
In the present invention, the lithium source, the precursor Ni xMny(OH)2, and the dopant are preferably mixed by stirring. The stirring and mixing speed is preferably 500-1000 r/min, and can be particularly 500r/min、550r/min、600r/min、650r/min、700r/min、750r/min、800r/min、850r/min、900r/min、950r/min、1000r/min., and the stirring and mixing time is preferably 20-50 min, and can be particularly 20min, 25min, 30min, 35min, 40min, 45min and 50min. In the invention, the mixing is preferably carried out in a protective atmosphere, so that the influence of water vapor in the compressed air on the uniformity of the mixed materials caused by entering the mixing device is avoided; the gas species for providing the protective atmosphere in the present invention is not particularly limited, and may be inert gas such as nitrogen or argon, etc. which are conventional in the art. After the mixing treatment, the evenly mixed mixture is obtained.
In the present invention, the above-mentioned mixture is followed by calcination. In the present invention, the conditions for the calcination are preferably: air atmosphere, heating rate 1-5 deg.c/min, roasting temperature 800-1000 deg.c and heat maintaining time 8-16 hr. According to the research of the applicant, in the preparation process of the invention, the cost of the material can be further reduced by adopting the air atmosphere, the integrity of the crystal form of the material is facilitated, more impurity phases in the material are easily caused by adopting the oxygen atmosphere, and the intercalation and deintercalation of lithium ions in the material are not facilitated. The heating rate can be specifically 1 ℃/min, 2 ℃/min, 3 ℃/min, 4 ℃/min and 5 ℃/min; according to the research of the applicant, in the preparation process, the morphology of the material subjected to the temperature rising rate roasting has a remarkable influence, under the temperature rising rate range, the roasting product with uniform morphology and uniform primary particles is favorable to be obtained, and if the temperature rising rate is too high, the roasting morphology is uneven and the primary particles have larger difference. The roasting temperature can be 800℃、810℃、820℃、830℃、840℃、850℃、860℃、870℃、880℃、890℃、900℃、910℃、920℃、930℃、940℃、950℃、960℃、970℃、980℃、990℃、1000℃., and the heat preservation time can be 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h and 16h.
After roasting in step a), the lithium source, the nickel-manganese hydroxide and the doping agent undergo oxidation-reduction reaction, and the crystal structure of the material is more stable due to the existence of the doping agent. The main components of the obtained primary roasting material except the doping components are Li 2NixMny(OH)2, the values of x and y are the same as those in the technical scheme, specifically, x is more than or equal to 0.5 and less than or equal to 0.8, and specifically, 0.5, 0.6, 0.7 and 0.8 can be obtained; y is more than or equal to 0.2 and less than or equal to 0.5, and can be specifically 0.2, 0.3, 0.4 and 0.5; and x+y=1.
The primary roasting material obtained in the step a) has the advantages of narrower particle size distribution and stable average particle size, and the primary particle size is between 0.3 and 0.8 mu m, and has the advantages of short charge transmission path, strong conductivity and high compaction density. The primary calcined material obtained in step a) of the present invention has an overall average particle diameter D50 of 3 to 10. Mu.m, specifically 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm as measured by a laser particle sizer, and the particle diameter refers to the diameter. In the invention, the specific surface area of the primary roasting material obtained in the step a) is 0.3-0.9 m 2/g, and the specific surface area can be 0.3m2/g、0.4m2/g、0.5m2/g、0.6m2/g、0.7m2/g、0.8m2/g、0.9m2/g., and the residual lithium content of the primary roasting material obtained in the step a) is less than 0.2wt%. The larger the specific surface area is, the more favorable the diffusion of ions is, so that the rate performance is improved, but the surface energy is increased, and agglomeration is caused.
Regarding step b):
b) And mixing the primary roasting material with a coating agent, and roasting to obtain the cobalt-free monocrystal anode material.
In the invention, the coating agent is a transition metal compound; the transition metal compound is at least one selected from the group consisting of transition metal oxides, transition metal sulfides, transition metal fluorides, transition metal hydroxides, transition metal carbonates, and transition metal acetates, preferably transition metal oxides. In the present invention, the transition metal in the coating agent is at least one of W, mo, zr, ca, ba, si, ti, more preferably at least one of W, mo, zr, and Ti, i.e., the coating agent is preferably at least one of WO 3、MoO2、ZrO2 and TiO 2. The doped metal oxide in the step a) of the invention, especially the metal oxide of W, mo and Zr, can be doped into the lattice of the positive electrode material in a more adaptive way, and is effectively combined with metal ions in the primary roasting material to form a covalent bond structure, thereby inhibiting cation mixed arrangement and effectively improving the cycle performance of the material. Meanwhile, the metal oxide coating layer, especially the metal oxide coating layer of W, mo, zr, ti, is added through the secondary roasting process of the step b), so that the combination capability of the primary roasting material and the transition metal oxide coating agent can be improved, compared with the method that the transition metal oxide coating agent is added into a lithium source and a precursor for co-roasting, the applicant has unexpectedly found that the transition metal oxide coating agent can be subjected to secondary roasting at a lower temperature and better coated on the surface of the primary roasting material, thereby being beneficial to the stability of the cobalt-free positive electrode material structure, reducing the gas yield of the cobalt-free material, and further improving the cycle performance of the cobalt-free positive electrode material by the synergistic effect of the step a).
In the invention, the dosage of the coating agent is preferably 0.05wt% -1wt% of the mass of the primary roasting material, and can be specifically 0.05wt％、0.10wt％、0.15wt％、0.20wt％、0.25wt％、0.30wt％、0.35wt％、0.40wt％、0.45wt％、0.50wt％、0.55wt％、0.60wt％、0.65wt％、0.70wt％、0.75wt％、0.80wt％、0.85wt％、0.90wt％、0.95wt％、1.00wt％.
In the present invention, the primary calcined material and the coating agent are preferably mixed by stirring. The stirring and mixing speed is preferably 500-1000 r/min, and can be particularly 500r/min、550r/min、600r/min、650r/min、700r/min、750r/min、800r/min、850r/min、900r/min、950r/min、1000r/min., and the stirring and mixing time is preferably 20-50 min, and can be particularly 20min, 25min, 30min, 35min, 40min, 45min and 50min. And (3) after the mixing treatment, obtaining the mixture.
In the present invention, the above-mentioned mixture is followed by calcination. In the present invention, the conditions for the calcination are preferably: air atmosphere, heating rate 1-5 deg.c/min, roasting temperature 400-600 deg.c and heat maintaining time 4-8 hr. Wherein the heating rate can be specifically 1 ℃/min, 2 ℃/min, 3 ℃/min, 4 ℃/min and 5 ℃/min. The baking temperature may be specifically 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃. The heat preservation time can be specifically 4h, 5h, 6h, 7h and 8h.
After roasting in step b), the coating agent forms a coating layer on the surface of the material through the peroxidation reaction with oxygen in the air, and the coating layer is attached to the surface of the material.
In the present invention, it is preferable that after the above-mentioned calcination, the following steps are further performed: sieving and demagnetizing. Wherein, the mesh number of the screen used for sieving is 300-400 meshes, and can be 300-350 meshes or 400 meshes. After sieving, demagnetizing is carried out. The method of the present invention is not particularly limited, and the method may be performed according to a conventional demagnetization operation in the art. After the treatment, the cobalt-free monocrystal anode material is obtained.
The cobalt-free monocrystal positive electrode material is a monocrystal material, and has high crystallinity and complete crystal form.
The invention also provides a cobalt-free monocrystal anode material prepared by the preparation method in the technical scheme.
The cobalt-free monocrystal anode material prepared by the invention is a core-shell structure material, the core is a cobalt-free binary monocrystal material, and the cladding shell is a transition metal oxide layer.
The invention also provides a lithium ion battery, wherein the positive electrode active material on the positive electrode is the cobalt-free monocrystal positive electrode material in the technical scheme.
The preparation method of the cobalt-free monocrystal anode material comprises the steps of firstly mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent, and roasting to obtain a primary roasting material; and mixing the primary roasting material with a coating agent, and roasting to obtain the cobalt-free monocrystal anode material. The step a) of doping transition metal oxides, particularly metal oxides of W, mo and Zr, can be doped into the lattice of the positive electrode material in a more adaptive manner, and effectively combines with metal ions in the primary roasting material to form a covalent bond structure, so that cation mixed discharge is inhibited, the compactness of the material is improved, the gas production is reduced, and the cycle performance of the material is effectively improved. Meanwhile, the secondary roasting process of the step b) is adopted to increase the transition metal oxide coating layer, especially the metal oxide coating layer of W, mo, zr, ti, so that the binding capacity of the primary roasting material and the transition metal oxide coating agent can be improved, compared with the method that the transition metal oxide coating agent is added into a lithium source and a precursor for co-roasting, the applicant has unexpectedly found that the transition metal oxide coating agent can be subjected to secondary roasting at a lower temperature and better coated on the surface of the primary roasting material, thereby being beneficial to the stability of the cobalt-free positive electrode material structure, reducing the gas production amount of the cobalt-free material, and further improving the cycle performance of the cobalt-free positive electrode material by the synergistic effect of the step a).
Test results show that the gram capacity of the positive electrode material obtained by the invention reaches over 184mAh/g after the first discharge under the charging and discharging multiplying power of 0.1C/0.1C in the voltage range of 4.4-3.0V; the capacity retention rate reaches more than 97.5% after the cycle of 50 weeks at normal temperature and 0.5C multiplying power at 25 ℃ under the voltage range of 4.4-3.0V.
For a further understanding of the present invention, preferred embodiments of the invention are described below in conjunction with the examples, but it should be understood that these descriptions are merely intended to illustrate further features and advantages of the invention, and are not limiting of the claims of the invention.
Example 1
A) Lithium carbonate, precursor Ni 0.55Mn0.45(OH)2 and doping agent ZrO 2 are put into a high-speed mixer, wherein the mol ratio of the precursor Ni 0.55Mn0.45(OH)2 to Li in a lithium source is 1.00:1.03, and the dosage of the doping agent is 0.10wt% of the total mass of the lithium source and the precursor. And (3) introducing nitrogen into the high-speed mixer, and stirring and mixing for 25min at the speed of 500r/min to obtain the uniformly mixed mixture. Then placing the mixture in an air atmosphere roller kiln, heating to 970 ℃ at a speed of 3 ℃/min, and carrying out heat preservation roasting for 10 hours to obtain a primary roasting material.
B) Adding a coating agent WO 3 into the primary roasting material, wherein the dosage of the coating agent WO 3 is 0.1 weight percent of the mass of the primary roasting material, and uniformly mixing; then, placing the mixture in an air atmosphere furnace, heating to 400 ℃ at a speed of 3 ℃/min, and preserving heat and roasting for 6 hours; then, the cobalt-free monocrystal anode material is obtained through 350 mesh sieving and demagnetizing.
Characterization:
XRD test is carried out on the primary roasting material obtained in the step a), and as a result, referring to FIG. 1, FIG. 1 is an XRD pattern of the primary roasting material obtained in the step a) in the example 1, it can be seen that the obtained ZrO 2 doped cobalt-free binary primary roasting material has high crystallinity and complete crystal form, and is a pure-phase lithium nickel manganese oxide material. SEM characterization of the primary baked material obtained in step a) is performed, and as a result, referring to FIG. 2, FIG. 2 is an SEM image of the primary baked material obtained in step a) in example 1, it can be seen that the obtained ZrO 2 doped cobalt-free binary primary baked material has relatively uniform granularity, and the average particle size D50 is 10 μm.
Example 2
A) Lithium hydroxide, precursor Ni 0.55Mn0.45(OH)2 and doping agent ZrO 2 are put into a high-speed mixer, wherein the mol ratio of the precursor Ni 0.55Mn0.45(OH)2 to Li in a lithium source is 1.00:1.00, and the dosage of the doping agent is 0.05wt% of the total mass of the lithium source and the precursor. And (3) introducing nitrogen into the high-speed mixer, and stirring and mixing for 40min at the speed of 800r/min to obtain the uniformly mixed mixture. Then placing the mixture in an air atmosphere roller kiln, heating to 950 ℃ at a speed of 4 ℃/min, and carrying out heat preservation roasting for 10 hours to obtain a primary roasting material.
B) Adding a coating agent WO 3 into the primary roasting material, wherein the dosage of the coating agent WO 3 is 0.5 weight percent of the mass of the primary roasting material, and uniformly mixing; then, placing the mixture in an air atmosphere furnace, heating to 500 ℃ at a speed of 5 ℃/min, and carrying out heat preservation and roasting for 7 hours; then sieving with 400 mesh sieve, and demagnetizing to obtain the cobalt-free monocrystal anode material.
Characterization: SEM characterization of the primary roasting material obtained in the step a) shows that the particle size is uniform, the particle size distribution is narrow, and the average particle diameter D50 is 5 mu m.
Example 3
A) Lithium carbonate, precursor Ni 0.75Mn0.25(OH)2 and doping agent ZrO 2 are put into a high-speed mixer, wherein the mol ratio of the precursor Ni 0.75Mn0.25(OH)2 to Li in a lithium source is 1.00:1.10, and the dosage of the doping agent is 0.15wt% of the total mass of the lithium source and the precursor. And (3) introducing nitrogen into the high-speed mixer, and stirring and mixing for 50min at the speed of 1000r/min to obtain the uniformly mixed mixture. Then placing the mixture in an air atmosphere roller kiln, heating to 1000 ℃ at a speed of 1 ℃/min, and carrying out heat preservation roasting for 16 hours to obtain a primary roasting material.
B) Adding a coating agent TiO 2 into the primary roasting material, wherein the dosage of the coating agent TiO 2 is 1.0 weight percent of the mass of the primary roasting material, and uniformly mixing; then, placing the mixture in an air atmosphere furnace, heating to 600 ℃ at a speed of 1 ℃/min, and preserving heat and roasting for 6 hours; then 300 mesh sieve and demagnetizing to obtain the cobalt-free monocrystal anode material.
Characterization: SEM characterization of the primary roasting material obtained in the step a) shows that the particle size is uniform, the particle size distribution is narrow, and the average particle diameter D50 is 9 mu m.
Example 4: product testing
9.0G of positive electrode active material, 0.5g of acetylene black conductive agent and 0.5g of PVDF binder are weighed, mixed, added with NMP solvent until the solid content is 70%, and uniformly dispersed to obtain positive electrode slurry. And coating the positive electrode slurry on the two sides of an aluminum foil (with the thickness of 16 mu m), and drying to obtain the positive electrode plate. The positive electrode plate, the metal lithium plate negative electrode plate, the ceramic diaphragm (thickness 16 μm) and LiPF 6 electrolyte (concentration 1mol/L, solvent is mixed solvent of ethyl carbonate EC: dimethyl carbonate DMC: diethyl carbonate EMC volume ratio=1:1:1) are assembled into a half battery in an anaerobic glove box by adopting a standard half battery configuration and adopting a CR2032 button battery as a battery shell.
The materials obtained in examples 1 to 3 were used as positive electrode active materials, respectively, and assembled into button half batteries according to the above-described procedure, and then charge and discharge tests were performed at a charge and discharge rate of 0.1C/0.1C in a voltage range of 4.4 to 3.0V, to measure gram capacity of first discharge. And (3) circulating for 50 weeks at normal temperature and 0.5C multiplying power at 25 ℃ in a voltage range of 4.4-3.0V, and testing the capacity retention rate. The results are shown in Table 1.
The results of the normal temperature cycle performance test of example 1 are shown in fig. 3. Meanwhile, the cycle performance was tested at a high temperature of 45℃for example 1 (other test conditions are unchanged), and the result is that the capacity retention rate after 50 weeks of the cycle was 98.3% as shown in FIG. 4.
Table 1: electrochemical performance test results
As can be seen from the test results in the table 1, the first discharge gram capacity of the positive electrode material obtained by the invention reaches more than 184mAh/g under the charging and discharging multiplying power of 0.1C/0.1C in the voltage range of 4.4-3.0V; the material is circulated for 50 weeks at normal temperature and 0.5C multiplying power at 25 ℃ in a voltage range of 4.4-3.0V, and the capacity retention rate reaches more than 97.5%, so that the material has excellent capacity performance and circulation performance.
Comparative example 1
The procedure is as in example 2, except that in step a), the atmosphere during mixing is air, the atmosphere during firing is an oxygen atmosphere having an oxygen concentration of 95% and the heating rate is 10℃per minute.
Performance testing was performed according to the test method in example 4, and the results showed that the capacity retention of the material obtained in comparative example 1 after 50 weeks of circulation was 93.21%.
Comparative example 2
The procedure is as in example 2, except that in step a) the dopant ZrO 2 is replaced by SnO 2 and the capping agent WO 3 is replaced by SnO 2.
Performance testing was performed according to the test method in example 4, and the result showed that the capacity retention of the material obtained in comparative example 2 after 50 weeks of circulation was 89.23%.
From the above test results, it can be seen that the capacity retention rate of comparative example 1 is significantly deteriorated compared with example 2, and it is proved that the circulation performance of the material can be effectively improved by adopting an inert atmosphere in the mixing process, adopting an air atmosphere in the roasting process and controlling a proper temperature rising rate in the step a) of the present invention. Compared with the example 2, the capacity retention rate of the comparative example 2 is obviously poor, and the invention proves that the circulating performance of the material can be effectively improved by adopting a certain doping agent and a coating agent.
The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to aid in understanding the method of the invention and its core concept, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims. The scope of the patent protection is defined by the claims and may include other embodiments that occur to those skilled in the art. Such other embodiments are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
Claims (9)
1. The preparation method of the cobalt-free monocrystal anode material is characterized by comprising the following steps of:
a) Mixing a lithium source, a precursor Ni xMny(OH)2 and a doping agent in a protective atmosphere, and roasting in an air atmosphere to obtain a primary roasting material; the lithium source is lithium carbonate; the precursor Ni xMny(OH)2 is Ni 0.75Mn0.25(OH)2; the doping agent is ZrO 2; the dosage of the doping agent is 0.15-0.2 wt% of the total mass of the lithium source and the precursor Ni xMny(OH)2; the roasting conditions are as follows: heating rate is 1-2 ℃/min, and roasting temperature is 990-1000 ℃;
b) Mixing the primary roasting material with a coating agent, and roasting in an air atmosphere to obtain a cobalt-free monocrystal anode material;
The coating agent is TiO 2; the consumption of the coating agent is 0.8-1 wt% of the mass of the primary roasting material;
the roasting conditions are as follows: the temperature rising rate is 1-2 ℃/min, and the roasting temperature is 550-600 ℃.
2. The method according to claim 1, wherein in step a), the conditions of the calcination further include: the heat preservation time is 8-16 h.
3. The method according to claim 1, wherein in step b), the conditions of the firing further include: the heat preservation time is 4-8 hours.
4. The preparation method according to claim 1, wherein the molar ratio of Li in the precursor Ni xMny(OH)2 to the lithium source is 1.00:1.00-1.10.
5. The method of claim 1, wherein in step a), the mixing is stirring mixing;
The stirring and mixing conditions are as follows: the stirring speed is 500-1000 r/min, and the stirring time is 20-50 min.
6. The method according to claim 1, wherein in step a), step b), after calcination, is further performed: sieving and demagnetizing;
the mesh number of the screen used for sieving is 300-400 meshes.
7. The process according to claim 1, wherein the primary calcined material obtained in step a) has an average particle diameter D50 of 3 to 10. Mu.m, a specific surface area of 0.3 to 0.9m 2/g and a residual lithium content of < 0.2 wt.%.
8. A cobalt-free single crystal positive electrode material produced by the production method according to any one of claims 1 to 7.
9. A lithium ion battery, wherein the positive electrode active material on the positive electrode is the cobalt-free single crystal positive electrode material according to claim 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310002203.3A CN117117109B (en) | 2023-01-03 | 2023-01-03 | Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310002203.3A CN117117109B (en) | 2023-01-03 | 2023-01-03 | Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117117109A CN117117109A (en) | 2023-11-24 |
| CN117117109B true CN117117109B (en) | 2024-08-02 |
Family
ID=88806204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310002203.3A Active CN117117109B (en) | 2023-01-03 | 2023-01-03 | Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117117109B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112886006A (en) * | 2021-04-28 | 2021-06-01 | 蜂巢能源科技有限公司 | Single-crystal high-nickel cathode material and preparation method and application thereof |
| CN113060776A (en) * | 2021-03-31 | 2021-07-02 | 蜂巢能源科技有限公司 | A layered cobalt-free positive electrode material, its preparation method and lithium ion battery |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113072101B (en) * | 2021-03-30 | 2023-04-07 | 蜂巢能源科技有限公司 | Cobalt-free cathode material and preparation method and application thereof |
| CN115440941A (en) * | 2021-06-01 | 2022-12-06 | 天津国安盟固利新材料科技股份有限公司 | Preparation method of cobalt-free lithium ion battery anode material |
-
2023
- 2023-01-03 CN CN202310002203.3A patent/CN117117109B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113060776A (en) * | 2021-03-31 | 2021-07-02 | 蜂巢能源科技有限公司 | A layered cobalt-free positive electrode material, its preparation method and lithium ion battery |
| CN112886006A (en) * | 2021-04-28 | 2021-06-01 | 蜂巢能源科技有限公司 | Single-crystal high-nickel cathode material and preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117117109A (en) | 2023-11-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11955633B2 (en) | Positive electrode material and preparation method and usage thereof | |
| US10056612B2 (en) | Lithium manganate particles for non-aqueous electrolyte secondary battery, process for producing the same, and nonaqueous electrolyte secondary battery | |
| JP5656012B2 (en) | Positive electrode active material powder for non-aqueous electrolyte secondary battery, method for producing the same, and non-aqueous electrolyte secondary battery | |
| CN110504432B (en) | Nickel cobalt lithium manganate composite material and preparation method thereof, lithium battery positive electrode and preparation method thereof, lithium battery and power supply device | |
| WO2010064440A1 (en) | Powder of lithium complex compound particles, method for producing the same, and nonaqueous electrolyte secondary cell | |
| WO2011108720A1 (en) | Positive-electrode active material for lithium ion battery, positive electrode for lithium battery, and lithium ion battery | |
| EP4024519A1 (en) | Positive electrode material, preparation method therefor and lithium ion battery | |
| US11996560B1 (en) | Positive electrode material of lithium-ion battery and preparation method therefor | |
| CN112490444A (en) | Lithium ion secondary battery positive electrode material and preparation method thereof | |
| CN116581283B (en) | A high-performance lithium manganese oxide positive electrode material with low oxygen vacancies and a preparation method thereof | |
| CN116404140A (en) | Multi-element trace co-doped lithium iron phosphate/carbon composite positive electrode material and preparation method and application thereof | |
| CN111682170A (en) | A kind of single crystal ternary cathode material and preparation method and application thereof | |
| WO2024093679A1 (en) | Positive electrode material, positive electrode sheet comprising same, and battery | |
| JP2011249293A (en) | Lithium transition metal compound and its manufacturing method, and lithium ion battery | |
| CN116031380B (en) | Polycrystalline sodium ion positive electrode material and preparation method and application thereof | |
| CN118231612A (en) | Rare earth element doped lithium iron manganese phosphate/carbon coated positive electrode material and preparation method and application thereof | |
| CN115064670B (en) | A method for preparing doped and coated sodium nickel manganate cathode material | |
| JP2025501057A (en) | Positive electrode active material and lithium ion battery | |
| EP4203102A1 (en) | Boron oxide-coated quaternary positive electrode material, and preparation method therefor and application thereof | |
| CN114388777A (en) | Positive electrode material with high peak intensity ratio, preparation method and application thereof | |
| WO2024095975A1 (en) | Method for manufacturing positive electrode active material for lithium-ion secondary battery | |
| CN117117109B (en) | Cobalt-free monocrystal positive electrode material, preparation method thereof and lithium ion battery | |
| CN114314693A (en) | Modified ternary cathode material, preparation method thereof and lithium ion battery | |
| US20220033276A1 (en) | Method for producing positive electrode active substance for non-aqueous electrolyte secondary battery | |
| WO2024095980A1 (en) | Method for manufacturing positive electrode active material for lithium-ion 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 | ||
| GR01 | Patent grant |