CN117558904A - Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof - Google Patents
Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof Download PDFInfo
- Publication number
- CN117558904A CN117558904A CN202410038059.3A CN202410038059A CN117558904A CN 117558904 A CN117558904 A CN 117558904A CN 202410038059 A CN202410038059 A CN 202410038059A CN 117558904 A CN117558904 A CN 117558904A
- Authority
- CN
- China
- Prior art keywords
- reaction
- solution
- cobalt
- concentration
- precursor
- 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
- 239000011258 core-shell material Substances 0.000 title claims abstract description 49
- 238000002360 preparation method Methods 0.000 title claims abstract description 16
- 239000007774 positive electrode material Substances 0.000 title abstract description 34
- 238000006243 chemical reaction Methods 0.000 claims abstract description 194
- 239000002243 precursor Substances 0.000 claims abstract description 89
- 238000000975 co-precipitation Methods 0.000 claims abstract description 49
- 238000005245 sintering Methods 0.000 claims abstract description 40
- 238000000034 method Methods 0.000 claims abstract description 33
- 239000010405 anode material Substances 0.000 claims abstract description 32
- 238000002156 mixing Methods 0.000 claims abstract description 27
- 230000008569 process Effects 0.000 claims abstract description 20
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000000203 mixture Substances 0.000 claims abstract description 13
- 239000011159 matrix material Substances 0.000 claims abstract description 12
- 238000012216 screening Methods 0.000 claims abstract description 10
- 239000000126 substance Substances 0.000 claims abstract description 9
- 239000000243 solution Substances 0.000 claims description 124
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 96
- 239000011259 mixed solution Substances 0.000 claims description 56
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 42
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 36
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 36
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 32
- VEQPNABPJHWNSG-UHFFFAOYSA-N Nickel(2+) Chemical compound [Ni+2] VEQPNABPJHWNSG-UHFFFAOYSA-N 0.000 claims description 32
- 229910001437 manganese ion Inorganic materials 0.000 claims description 32
- 229910001453 nickel ion Inorganic materials 0.000 claims description 32
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 claims description 27
- 239000008139 complexing agent Substances 0.000 claims description 27
- 239000010406 cathode material Substances 0.000 claims description 24
- 239000002245 particle Substances 0.000 claims description 24
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical group [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 23
- 239000001301 oxygen Substances 0.000 claims description 23
- 229910052760 oxygen Inorganic materials 0.000 claims description 23
- 229910021529 ammonia Inorganic materials 0.000 claims description 21
- 239000011572 manganese Substances 0.000 claims description 20
- 238000005086 pumping Methods 0.000 claims description 20
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 16
- 238000001816 cooling Methods 0.000 claims description 16
- 229910052727 yttrium Inorganic materials 0.000 claims description 16
- 238000007873 sieving Methods 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 10
- 239000007788 liquid Substances 0.000 claims description 10
- 229910052759 nickel Inorganic materials 0.000 claims description 10
- 229910052748 manganese Inorganic materials 0.000 claims description 9
- 238000000926 separation method Methods 0.000 claims description 9
- 238000005406 washing Methods 0.000 claims description 9
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 8
- 239000001569 carbon dioxide Substances 0.000 claims description 8
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 8
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 6
- 239000007789 gas Substances 0.000 claims description 6
- 150000002696 manganese Chemical class 0.000 claims description 6
- 150000002815 nickel Chemical class 0.000 claims description 6
- 230000006911 nucleation Effects 0.000 claims description 6
- 238000010899 nucleation Methods 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 6
- 230000035484 reaction time Effects 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- 150000002500 ions Chemical class 0.000 claims description 4
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 claims description 4
- 230000000630 rising effect Effects 0.000 claims description 4
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Substances [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 3
- 239000002184 metal Substances 0.000 claims description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-M Acetate Chemical compound CC([O-])=O QTBSBXVTEAMEQO-UHFFFAOYSA-M 0.000 claims description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 2
- 229910002651 NO3 Inorganic materials 0.000 claims description 2
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 claims description 2
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 2
- 239000007864 aqueous solution Substances 0.000 claims description 2
- VNEBWJSWMVTSHK-UHFFFAOYSA-L disodium;3-hydroxynaphthalene-2,7-disulfonate Chemical compound [Na+].[Na+].C1=C(S([O-])(=O)=O)C=C2C=C(S([O-])(=O)=O)C(O)=CC2=C1 VNEBWJSWMVTSHK-UHFFFAOYSA-L 0.000 claims description 2
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims description 2
- 229910052808 lithium carbonate Inorganic materials 0.000 claims description 2
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims description 2
- 229910000027 potassium carbonate Inorganic materials 0.000 claims description 2
- 230000001681 protective effect Effects 0.000 claims description 2
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims 1
- 239000011148 porous material Substances 0.000 claims 1
- 239000000463 material Substances 0.000 abstract description 26
- 229910001416 lithium ion Inorganic materials 0.000 abstract description 14
- 238000009792 diffusion process Methods 0.000 abstract description 6
- 230000008859 change Effects 0.000 abstract description 2
- 229910003002 lithium salt Inorganic materials 0.000 abstract description 2
- 159000000002 lithium salts Chemical class 0.000 abstract description 2
- 230000001351 cycling effect Effects 0.000 abstract 1
- 239000012266 salt solution Substances 0.000 description 41
- 229940099596 manganese sulfate Drugs 0.000 description 16
- 239000011702 manganese sulphate Substances 0.000 description 16
- 235000007079 manganese sulphate Nutrition 0.000 description 16
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 description 16
- LGQLOGILCSXPEA-UHFFFAOYSA-L nickel sulfate Chemical compound [Ni+2].[O-]S([O-])(=O)=O LGQLOGILCSXPEA-UHFFFAOYSA-L 0.000 description 16
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 description 16
- 230000000052 comparative effect Effects 0.000 description 15
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 14
- 238000010438 heat treatment Methods 0.000 description 14
- -1 yttrium ions Chemical class 0.000 description 14
- 239000010410 layer Substances 0.000 description 13
- 229910000347 yttrium sulfate Inorganic materials 0.000 description 10
- RTAYJOCWVUTQHB-UHFFFAOYSA-H yttrium(3+);trisulfate Chemical compound [Y+3].[Y+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RTAYJOCWVUTQHB-UHFFFAOYSA-H 0.000 description 10
- 238000000498 ball milling Methods 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 8
- 230000014759 maintenance of location Effects 0.000 description 7
- 229910052757 nitrogen Inorganic materials 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 238000009826 distribution Methods 0.000 description 6
- 239000003792 electrolyte Substances 0.000 description 6
- 150000001875 compounds Chemical class 0.000 description 5
- 229910052698 phosphorus Inorganic materials 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N argon Substances [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 238000005303 weighing Methods 0.000 description 4
- 150000003746 yttrium Chemical class 0.000 description 4
- 229910052786 argon Inorganic materials 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 238000009831 deintercalation Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 238000007599 discharging Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 3
- 239000012716 precipitator Substances 0.000 description 3
- 238000004080 punching Methods 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 239000011888 foil Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010183 spectrum analysis Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 239000006245 Carbon black Super-P Substances 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 230000001174 ascending effect Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 238000002149 energy-dispersive X-ray emission spectroscopy Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 238000009432 framing Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009830 intercalation Methods 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 239000004005 microsphere Substances 0.000 description 1
- 239000011268 mixed slurry Substances 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000007086 side reaction Methods 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
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G53/00—Compounds of nickel
- C01G53/40—Nickelates
- C01G53/70—Nickelates containing rare earth, e.g. LaNiO3
-
- 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
- H01M4/04—Processes of manufacture in general
- H01M4/0471—Processes of manufacture in general involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/85—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by XPS, EDX or EDAX data
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Organic Chemistry (AREA)
- Composite Materials (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Manufacturing & Machinery (AREA)
- Battery Electrode And Active Subsutance (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention discloses a cobalt-free positive electrode material with a porous core-shell structure and a preparation method thereof, wherein the chemical composition formula of the positive electrode material is as follows. Co-free precursor with porous core-shell structure is synthesized by coprecipitation method, and the first time by adjusting component change in the reaction processFirstly, a loose porous core is generated, then, a double-shell layer with stable components is generated on the surface of the core, and the concentration of R element contained in the shell layer is gradually increased from the inner shell layer to the outer shell layer. Fully mixing the precursor with lithium salt, performing primary sintering, crushing and crushing to obtain a cobalt-free anode material matrix with a porous core-shell structure, uniformly mixing the matrix with a B source and a P source, performing secondary sintering and screening to obtain the cobalt-free anode material with the porous core-shell structure. The positive electrode material prepared by the method improves the problem of poor cycling stability of the material in the charge and discharge process on the basis of ensuring the capacity, and meanwhile, the porous structure of the inner core provides a multi-layer lithium ion diffusion channel, so that the multiplying power performance of the material is effectively improved.
Description
Technical Field
The invention belongs to the technical field of lithium ion secondary batteries, and particularly relates to a cobalt-free positive electrode material with a porous core-shell structure and a preparation method thereof.
Background
The current development of human society has a growing demand for lithium ion secondary batteries, and various challenges are presented to the supply of raw materials. In particular, in layersThe Co resource which is relatively scarce in reserve is an important resource for world-wide reserve. In the near future, the demand for Co will far exceed the supply. Therefore, in order to alleviate the problem of limited secondary battery development caused by shortage of Co resources to some extent, removal or reduction of Co from NCM layered oxide cathode materials is an effective means for alleviating Co resource shortage at present.
In NCM, the presence of Co can provide the necessary structural stability for the positive electrode material and accelerate the intercalation kinetics of lithium ions. As the Co content is removed or reduced, the chemical stability and structural stability of the material surface gradually deteriorate, resulting in poor cycle performance and thermal stability. And bulk doping can enable elements to go deep into the lattice of the material, so that the material can simultaneously achieve stability and electrochemical performance.
CN112103496B discloses a gradient cathode material prepared by doping at the time of sintering with lithium salt, and doping during sintering generally has the disadvantages of high energy consumption and many processes by changing the sintering temperature or increasing the sintering process in order to ensure the doping amount and improve the doping uniformity.
The cobalt-free core-shell structure anode material has lower capacity due to the components and structural factors, but has certain defects because the circulation stability of the anode material is improved due to the relatively stable shell layer of the outer layer. The defect of the cobalt-free core-shell structure anode material can be effectively improved by controlling the addition amount of the doping agent in the precursor synthesis process. Therefore, in the precursor synthesis stage, one or more elements are doped to replace cobalt element, meanwhile, the internal morphology composition of the precursor is improved, the structural stability of the positive electrode material is improved, and the B source and the P source are coated on the surface of the synthesized positive electrode material, so that the multiplying power and the cycle performance of the material are further improved.
Disclosure of Invention
The invention aims to overcome the defects that doping in the sintering process can cause high energy consumption and more working procedures, and provides a cobalt-free anode material with a porous core-shell structure and a preparation method thereof. The method is simple and controllable, and the cobalt-free positive electrode material has higher capacity and good cycle performance.
In order to achieve the above purpose, the invention provides a preparation method of a cobalt-free cathode material with a porous core-shell structure, which comprises the following steps:
step one: preparing a mixed solution A containing nickel and manganese, wherein the molar ratio of nickel ions to manganese ions in the mixed solution A is (85-9)5): (5-15), wherein the sum of the concentration of nickel ions and manganese ions in the mixed solution A is 2.00 mol/L-4.00 mol/L; pumping the mixed solution A into a first reaction kettle at a rate of 2.5L/h-5L/h under the atmosphere of protective gas, and simultaneously adding a precipitant solution and a complexing agent solution into the first reaction kettle to perform a first coprecipitation reaction to obtain a precursor core part, wherein the molecular formula of the precursor core part isWherein a is more than or equal to 0.8 and less than or equal to 0.95, b is more than or equal to 0.05 and less than or equal to 0.2; the concentration of the precipitant solution is 2 mol/L-4 mol/L, the complexing agent solution is 1 mol/L-4 mol/L ammonia water solution, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the first reaction kettle is kept between 4g/L and 12g/L, the temperature is controlled between 40 ℃ and 70 ℃, the pH of the reaction is between 10.5 and 13, and the rotating speed of the reaction is between 450rpm and 500rpm; stopping the reaction when the nucleation D50 grows to 2.30-4.0 mu m in the first stage;
step two: preparing a mixed solution B containing nickel, manganese and R, wherein the molar ratio of nickel ions, manganese ions and R ions in the mixed solution B is (80-85): (10-20): (0.5-1.5), wherein the sum of the concentrations of nickel ions, manganese ions and R ions in the mixed solution B is 2.00 mol/L-4.00 mol/L; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the rate of 9-12L/h, simultaneously adding a precipitant solution and a complexing agent solution into the second reaction kettle, wherein the concentration of the precipitant solution is 2-4 mol/L, the concentration of the complexing agent solution is 1-4 mol/L of ammonia water solution, and slowly adding the mixed solution B to perform secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 5g/L and 15g/L, the pH of the reaction is between 10 and 12, and the rotating speed of the reaction is between 480 and 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 6.5-8.0 mu m;
step three: preparing a mixed solution C containing nickel, manganese and R, dissolving nickel salt, manganese salt and R salt powder in pure water, and preparing the mixed solution C with the total concentration of 2.00mol/L to 4.00mol/L according to the molar ratio of (70-80): (15-30): (1.5-3); overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step into a third reaction kettle at the rate of 12-15L/h through a second reaction kettle, and simultaneously adding a precipitant solution, a complexing agent solution and a mixed solution C into the third reaction kettle for a third coprecipitation reaction, wherein the concentration of the precipitant solution is 2-4 mol/L, and the concentration of the complexing agent solution is 1-4 mol/L of ammonia water solution; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 7g/L and 15g/L, the pH of the reaction is between 10.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is between 550 and 600rpm; stopping the reaction when the final grain size grows to 8.5-10.0 mu m;
step four: carrying out solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain a cobalt-free precursor with a porous core-shell structure;
step five: uniformly mixing the precursor obtained in the fourth step with one or two of lithium carbonate and lithium hydroxide, and sintering at a high temperature of 650-950 ℃ for 10-15 h; the sintering atmosphere is oxygen, air with moisture and carbon dioxide removed or a mixed gas atmosphere of the oxygen, the air with moisture and the carbon dioxide removed; the temperature rising rate is 2-8 ℃/min; crushing, crushing and sieving after cooling;
step six: uniformly mixing the anode material matrix obtained in the step five with a source B and a source P, and then performing secondary sintering at 300-550 ℃ for 4-8 hours; the sintering atmosphere is oxygen, air with moisture and carbon dioxide removed or a mixed gas atmosphere of the oxygen, the air with moisture and the carbon dioxide removed; the temperature rising rate is 2-8 ℃/min; and cooling and sieving to obtain the cobalt-free anode material with the porous core-shell structure.
Preferably, the mixed solution A, the mixed solution B and the mixed solution C are one or more of nitrate, sulfate, chloride and acetate solutions of nickel and manganese.
Preferably, the precipitant solution is one or more of potassium hydroxide, potassium carbonate, sodium hydroxide, and sodium carbonate aqueous solution.
Preferably, in the fifth step, the molar ratio of the total mole of the metal in the precursor to the mole of the lithium element is 1:1.04-1.1.
Preferably, R is one or more of Al, Y, nb, ce, ti, ta;b source isThe method comprises the steps of carrying out a first treatment on the surface of the The P source is->。
The invention also provides a cobalt-free anode material with a porous core-shell structure, wherein the chemical composition formula of the cobalt-free anode material with the porous core-shell structure is as followsWherein a is more than or equal to 1.04 and less than or equal to 1.1,0.8, x is more than or equal to 0.95,0.005 and y is more than or equal to 0.03,0.0005 and e is more than or equal to 0.01,0.0005 and f is more than or equal to 0.01. The R element is one or more of Al, Y, nb, ce, ti, ta. The concentration of the R element is gradually increased from an inner shell layer to an outer shell layer of the positive electrode material, the inner core is loose and porous, and the porosity of the section average value of single particles or a plurality of particles is 5-16%.
Compared with the prior art, the invention has the following beneficial effects:
1. the cobalt-free positive electrode material with the porous structure comprises an inner core, an inner shell layer and an outer shell, wherein the inner shell layer and the outer shell are respectively doped with doping elements with concentration gradient distribution. The concentration ratio from inside to outside is increased, the concentration on the surface of the particles is higher, the interface between the material and the electrolyte is more stable, and the occurrence of side reaction is reduced.
2. The nickel content is in a descending trend from the inner core to the outer shell of the precursor material, the manganese content and doping elements are gradually increased to be in an ascending trend, the distribution is favorable for the diffusion of lithium ions, the porous structure of the precursor further shortens the diffusion path of the lithium ions, promotes the deintercalation of the lithium ions, and strengthens the diffusion kinetics of the lithium ions. The surface of the doped precursor has higher concentration of doping elements, so that the reactivity of the material to electrolyte can be effectively reduced, and the operation stability and safety of the whole lithium ion battery can be improved. The doping effect is better than sintering doping effect in the precursor, and meanwhile, the problem that the capacity is greatly reduced due to excessive doping amount is avoided, so that the energy density of the whole lithium ion battery is increased, and the service life is prolonged.
3. The surface of the cobalt-free anode material with the porous core-shell structure is coated by a dry method for B, P co-coating, the method is simple and easy to operate, and the additive is low in cost. The coating layer can effectively inhibit the interface reaction between the electrolyte and the positive electrode material, and reduce the surface structure damage, thereby improving the first coulomb efficiency and the initial discharge specific capacity of the material, and simultaneously having good multiplying power and cycle performance.
Drawings
FIG. 1 is a block diagram of the preparation of example 3A cross section of the cobalt-free precursor of the porous core-shell structure;
FIG. 2 is a graph prepared in comparative example 3A cross section of the cobalt-free precursor;
fig. 3 is a graph showing the high temperature cycle retention ratio of the soft pack batteries of the positive electrode materials prepared in examples 1, 2, 3, and 4 and comparative examples 1, 2, and 3;
FIG. 4 is a graph showing the discharge capacity at different rates of the soft pack batteries of the positive electrode materials prepared in examples 3 and 4 and comparative example 3;
fig. 5 is a graph showing the different rate discharge capacity retention ratios of the soft pack batteries of the positive electrode materials prepared in examples 3 and 4 and comparative example 3;
fig. 6 is an EDS analysis chart of the positive electrode material prepared in example 3.
Detailed Description
The technical scheme of the invention is further described below by the specific embodiments with reference to the accompanying drawings.
Example 1
The preparation method of the cobalt-free cathode material with the porous core-shell structure comprises the following steps:
step one: preparing a first salt solution containing nickel sulfate and manganese sulfate, wherein the mole ratio of nickel ions to manganese ions in the first salt solution is 95:5, the sum of the concentration of nickel ions and the concentration of manganese ions in the first salt solution is 2.00mol/L, namely a mixed solution A; pumping the mixed solution A into a first reaction kettle at a rate of 4L/h under the atmosphere of nitrogen, and simultaneously introducing into a first reaction kettleAdding sodium hydroxide solution serving as a precipitator solution and ammonia water solution serving as a complexing agent solution into a reaction kettle to perform a first coprecipitation reaction to obtain a precursor core part; the concentration of the sodium hydroxide solution is 3mol/L, the concentration of the ammonia water solution is 3mol/L, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the first reaction kettle is kept between 7.5g/L and 8g/L, the temperature is controlled at 50 ℃, the pH of the reaction is between 11.5 and 12, and the rotating speed of the reaction is 500rpm; observing the size of the precursor D50 through a Markov 3000 laser particle sizer test, and immediately stopping the reaction when the nucleation D50 in the first stage grows to 3.5-4.0 mu m, wherein the molecular formula of the inner core part of the precursor is as follows：
Step two: preparing a second salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the second salt solution is 85:14.5:0.5, the sum of the concentration of nickel ions, the concentration of manganese ions and the concentration of yttrium ions in the second salt solution is 2.00mol/L, namely the mixed solution B; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the speed of 9L/h, simultaneously adding a sodium hydroxide solution which is used as a precipitant solution and an ammonia water solution which is used as a complexing agent solution into the second reaction kettle, wherein the concentration of the sodium hydroxide solution is 3mol/L, the concentration of the ammonia water solution is 3mol/L, and slowly adding the mixed solution B to carry out secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 7.7g/L and 8.5g/L, the pH of the reaction is between 11.2 and 11.8, and the rotating speed of the reaction is 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 7.4-8.0 mu m;
step three: preparing a third salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, dissolving nickel salt, manganese salt and yttrium salt powder in pure water, and preparing a mixed solution C with the total concentration of 2.00mol/L according to the molar ratio of 75:23.5:1.5; overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step, pumping the precursor inner core and the precursor inner shell into a third reaction kettle at a rate of 12L/h, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution, an ammonia water solution serving as a complexing agent solution and a mixed solution C into the third reaction kettle to perform a third coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 3mol/L, and the concentration of the ammonia water solution is 3mol/L; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 8g/L and 8.5g/L, the pH of the reaction is between 11.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is 600rpm; stopping the reaction when the final grain size grows to 9.3-10.0 mu m;
step four: performing solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain the precursor with the chemical formula ofIs a cobalt-free precursor of a porous core-shell structure;
step five: and (3) mixing the precursor obtained in the step (IV) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering conditions are that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 10 hours at 800 ℃ after two low-temperature sections of 2 hours, the heating rate is 3 ℃/min, crushed and crushed after cooling, and screened to obtain the cobalt-free anode material matrix with the porous core-shell structure；
Step six: and (3) mixing the positive electrode material matrix obtained in the step (V) with、/>Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material with the porous core-shell structure and coated with B, P.
Example 2
The preparation method of the cobalt-free cathode material with the porous core-shell structure comprises the following steps:
step one: preparing a first salt solution containing nickel sulfate and manganese sulfate, wherein nickel ions and manganese ions in the first salt solutionThe molar ratio of the seeds is 95:5, the sum of the concentration of nickel ions and the concentration of manganese ions in the first salt solution is 2.00mol/L, namely a mixed solution A; pumping the mixed solution A into a first reaction kettle at the rate of 4L/h under the atmosphere of nitrogen, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution and an ammonia water solution serving as a complexing agent solution into the first reaction kettle to perform a first coprecipitation reaction to obtain a core part of a precursor; the concentration of the sodium hydroxide solution is 3.5mol/L, the concentration of the ammonia water solution is 3.5mol/L, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the first reaction kettle is kept between 7.5g/L and 8g/L, the temperature is controlled at 50 ℃, the pH of the reaction is between 11.5 and 12, and the rotating speed of the reaction is 500rpm; observing the size of the precursor D50 through a Markov 3000 laser particle sizer test, and immediately stopping the reaction when the nucleation D50 in the first stage grows to 3.5-4.0 mu m, wherein the molecular formula of the inner core part of the precursor is as follows；
Step two: preparing a second salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the second salt solution is 85:14.5:0.5, the sum of the concentration of nickel ions, the concentration of manganese ions and the concentration of yttrium ions in the second salt solution is 2.00mol/L, namely the mixed solution B; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the speed of 9L/h, simultaneously adding a sodium hydroxide solution which is used as a precipitant solution and an ammonia water solution which is used as a complexing agent solution into the second reaction kettle, wherein the concentration of the sodium hydroxide solution is 3.5mol/L, the concentration of the ammonia water solution is 3.5mol/L, and slowly adding the mixed solution B to carry out secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 7.7g/L and 8.5g/L, the pH of the reaction is between 11.2 and 11.8, and the rotating speed of the reaction is 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 7.4-8.0 mu m;
step three: preparing a third salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, dissolving nickel salt, manganese salt and yttrium salt powder in pure water, and preparing a mixed solution C with the total concentration of 2.00mol/L according to the mol ratio of 75:23:2; overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step, pumping the precursor inner core and the precursor inner shell into a third reaction kettle at a rate of 12L/h, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution, an ammonia water solution serving as a complexing agent solution and a mixed solution C into the third reaction kettle to perform a third coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 3.5mol/L and the concentration of the ammonia water solution is 3.5mol/L; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 8g/L and 8.5g/L, the pH of the reaction is between 11.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is 600rpm; stopping the reaction when the final grain size grows to 9.3-10.0 mu m;
step four: performing solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain the precursor with the chemical formula ofIs a cobalt-free precursor of a porous core-shell structure;
step five: and (3) mixing the precursor obtained in the step (IV) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering conditions are that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 10 hours at 800 ℃ after two low-temperature sections of 2 hours, the heating rate is 3 ℃/min, crushed and crushed after cooling, and screened to obtain the cobalt-free anode material matrix with the porous core-shell structure；
Step six: and (3) mixing the positive electrode material matrix obtained in the step (V) with、/>Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material with the porous core-shell structure and coated with B, P.
Example 3
The preparation method of the cobalt-free cathode material with the porous core-shell structure comprises the following steps:
step one: preparing a first salt solution containing nickel sulfate and manganese sulfate, wherein the mole ratio of nickel ions to manganese ions in the first salt solution is 95:5, the sum of the concentration of nickel ions and the concentration of manganese ions in the first salt solution is 2.00mol/L, namely a mixed solution A; pumping the mixed solution A into a first reaction kettle at the rate of 4L/h under the atmosphere of nitrogen, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution and an ammonia water solution serving as a complexing agent solution into the first reaction kettle to perform a first coprecipitation reaction to obtain a core part of a precursor; the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 4mol/L, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the first reaction kettle is kept between 7.5g/L and 8g/L, the temperature is controlled at 50 ℃, the pH of the reaction is between 11.5 and 12, and the rotating speed of the reaction is 500rpm; observing the size of the precursor D50 through a Markov 3000 laser particle sizer test, and immediately stopping the reaction when the nucleation D50 in the first stage grows to 3.5-4.0 mu m, wherein the molecular formula of the inner core part of the precursor is as follows；
Step two: preparing a second salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the second salt solution is 85:14.5:0.5, the sum of the concentration of nickel ions, the concentration of manganese ions and the concentration of yttrium ions in the second salt solution is 2.00mol/L, namely the mixed solution B; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the speed of 9L/h, simultaneously adding a sodium hydroxide solution which is used as a precipitant solution and an ammonia water solution which is used as a complexing agent solution into the second reaction kettle, wherein the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 4mol/L, and slowly adding the mixed solution B to carry out secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 7.7g/L and 8.5g/L, the pH of the reaction is between 11.2 and 11.8, and the rotating speed of the reaction is 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 7.4-8.0 mu m;
step three: preparing a third salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, dissolving nickel salt, manganese salt and yttrium salt powder in pure water, and preparing a mixed solution C with the total concentration of 2.00mol/L according to the mol ratio of 75:22:3; overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step, pumping the precursor inner core and the precursor inner shell into a third reaction kettle at a rate of 12L/h, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution, an ammonia water solution serving as a complexing agent solution and a mixed solution C into the third reaction kettle to perform a third coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 4mol/L, and the concentration of the ammonia water solution is 4mol/L; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 8g/L and 8.5g/L, the pH of the reaction is between 11.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is 600rpm; stopping the reaction when the final grain size grows to 9.3-10.0 mu m;
step four: performing solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain the compound Ni 0.85 Mn 0.138 Y 0.012 (OH) 2 Is a cobalt-free precursor of a porous core-shell structure;
step five: and (3) mixing the precursor obtained in the step (IV) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering conditions are that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 10 hours at 800 ℃ after two low-temperature sections of 2 hours, the heating rate is 3 ℃/min, crushed and crushed after cooling, and sieved to obtain the cobalt-free anode material matrix Li with the porous core-shell structure 1.07 Ni 0.85 Mn 0.138 Y 0.012 O 2 ；
Step six: mixing the positive electrode material matrix obtained in the step five with H 3 BO 3 、NH 4 H 2 PO 4 Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material with the porous core-shell structure and coated with B, P.
Example 4
The preparation method of the cobalt-free cathode material with the porous core-shell structure comprises the following steps:
step one: preparing a first salt solution containing nickel sulfate and manganese sulfate, wherein the mole ratio of nickel ions to manganese ions in the first salt solution is 95:5, the sum of the concentration of nickel ions and the concentration of manganese ions in the first salt solution is 2.00mol/L, namely a mixed solution A; pumping the mixed solution A into a first reaction kettle at the rate of 4L/h under the atmosphere of nitrogen, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution and an ammonia water solution serving as a complexing agent solution into the first reaction kettle to perform a first coprecipitation reaction to obtain a core part of a precursor; the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 3mol/L, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the first reaction kettle is kept between 7.5g/L and 8g/L, the temperature is controlled at 50 ℃, the pH of the reaction is between 11.5 and 12, and the rotating speed of the reaction is 500rpm; observing the size of the precursor D50 through a Markov 3000 laser particle sizer test, and immediately stopping the reaction when the nucleation D50 in the first stage grows to 3.5-4.0 mu m, wherein the molecular formula of the inner core part of the precursor is Ni 0。95 Mn 0.05 (OH) 2 ；
Step two: preparing a second salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the second salt solution is 85:13.5:1.5, the sum of the concentration of nickel ions, the concentration of manganese ions and the concentration of yttrium ions in the second salt solution is 2.00mol/L, namely a mixed solution B; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the speed of 9L/h, simultaneously adding a sodium hydroxide solution which is used as a precipitant solution and an ammonia water solution which is used as a complexing agent solution into the second reaction kettle, wherein the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 3mol/L, and slowly adding the mixed solution B to carry out secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 7.7g/L and 8.5g/L, the pH of the reaction is between 11.2 and 11.8, and the rotating speed of the reaction is 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 7.4-8.0 mu m;
step three: preparing a third salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, dissolving nickel salt, manganese salt and yttrium salt powder in pure water, and preparing a mixed solution C with the total concentration of 2.00mol/L according to the mol ratio of 75:22:3; overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step, pumping the precursor inner core and the precursor inner shell into a third reaction kettle at a rate of 12L/h, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution, an ammonia water solution serving as a complexing agent solution and a mixed solution C into the third reaction kettle to perform a third coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 4mol/L, and the concentration of the ammonia water solution is 3mol/L; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 8g/L and 8.5g/L, the pH of the reaction is between 11.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is 600rpm; stopping the reaction when the final grain size grows to 9.3-10.0 mu m;
step four: performing solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain the compound Ni 0.85 Mn 0.135 Y 0.015 (OH) 2 Is a cobalt-free precursor of a porous core-shell structure;
step five: and (3) mixing the precursor obtained in the step (IV) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering conditions are that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 10 hours at 800 ℃ after two low-temperature sections of 2 hours, the heating rate is 3 ℃/min, crushed and crushed after cooling, and sieved to obtain the cobalt-free anode material matrix Li with the porous core-shell structure 1.07 Ni 0.85 Mn 0.135 Y 0.015 O 2 ；
Step six: mixing the positive electrode material matrix obtained in the step five with H 3 BO 3 、NH 4 H 2 PO 4 Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material with the porous core-shell structure and coated with B, P.
Comparative example 1
Step one: preparing a salt solution containing nickel sulfate and manganese sulfate, wherein the molar ratio of nickel ions to manganese ions in the salt solution is 85:15, the sum of the concentration of nickel ions and the concentration of manganese ions in the salt solution is 2.00mol/L;
step two: pumping a salt solution into a reaction kettle at a rate of 12L/h under the atmosphere of nitrogen, simultaneously adding a sodium hydroxide solution serving as a precipitator solution and an ammonia water solution serving as a complexing agent solution into the reaction kettle for coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 4mol/L, the temperature is controlled to be 50 ℃, the pH value of the reaction is 10.5-12, and the rotating speed of the reaction is 450rpm; stopping the reaction immediately after the coprecipitation reaction for 50 hours;
step three: after the reaction is finished, the obtained precursor is subjected to solid-liquid separation, washing, drying and screening to obtain the compound with the chemical formula of Ni 0.85 Mn 0.15 (OH) 2 Is a cobalt-free precursor of (a);
step four: according to the mole ratio of 1:1.07 weighing precursor Ni 0.85 Mn 0.15 (OH) 2 And adding yttrium oxide into the lithium hydroxide in a ball milling bottle, wherein Y accounts for 0.05% of the precursor mass, mixing for 4 hours in a ball milling mode, and sintering the mixed materials under the condition that the mixed materials are sintered for 2 hours at 600 ℃ to 750 ℃ in an oxygen atmosphere, then sintered for 10 hours at 800 ℃ after being sintered for 2 hours at the low temperature, wherein the heating rate is 3 ℃/min. Crushing, crushing and sieving after cooling;
step five: weighing the materials obtained in the step four, adding yttrium oxide into the ball-milling bottle, wherein Y accounts for 0.1% of the mass of the anode material, mixing for 4 hours in a ball-milling mode, and then sintering for 6 hours at 500 ℃ in an oxygen atmosphere, wherein the heating rate is 3 ℃/min. Cooling and sieving;
step six: weighing the materials obtained in the fifth step in a ball milling bottle, adding yttrium oxide into the ball milling bottle, wherein Y accounts for 0.15% of the positive electrode material in percentage by mass, and adding H into the ball milling bottle 3 BO 3 Wherein the mass percentage of the B is 0.1 percent of the positive electrode material, the materials are mixed for 4 hours in a ball milling mode, then sintered for 6 hours at 300 ℃ in an oxygen atmosphere, the heating rate is 3 ℃/min, and the materials are sieved after being cooled to obtain the gradient doped cobalt-free positive electrode material.
Comparative example 2
Step one: preparing a salt solution containing nickel sulfate and manganese sulfate, wherein the molar ratio of nickel ions to manganese ions in the salt solution is 85:15, the sum of the concentration of nickel ions and the concentration of manganese ions in the salt solution is 2.00mol/L;
step two: pumping a salt solution into a reaction kettle at a rate of 12L/h under the atmosphere of nitrogen, simultaneously adding a sodium hydroxide solution serving as a precipitator solution and an ammonia water solution serving as a complexing agent solution into the reaction kettle for coprecipitation reaction, wherein the concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 4mol/L, the temperature is controlled to be 50 ℃, the pH value of the reaction is 10.5-12, and the rotating speed of the reaction is 450rpm; stopping the reaction immediately after the coprecipitation reaction for 50 hours;
step three: after the reaction is finished, the obtained precursor is subjected to solid-liquid separation, washing, drying and screening to obtain the compound with the chemical formula of Ni 0.85 Mn 0.15 (OH) 2 Is a cobalt-free precursor of (a);
step four: and (3) mixing the precursor obtained in the step (III) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering conditions are that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 2 hours at 800 ℃ for 10 hours at a heating rate of 3 ℃/min, crushed and sieved;
step five: mixing the positive electrode material obtained in the step four with H 3 BO 3 、NH 4 H 2 PO 4 Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material.
Comparative example 3
Step one: preparing a first salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the first salt solution is 95:4:1, the sum of the concentrations of nickel ions, manganese ions and yttrium ions in the first salt solution is 2.00mol/L, namely a mixed solution A; preparing a second salt solution containing nickel sulfate, manganese sulfate and yttrium sulfate, wherein the mole ratio of nickel ions, manganese ions and yttrium ions in the second salt solution is 75:24:1, the sum of the concentration of nickel ions, the concentration of manganese ions and the concentration of yttrium ions in the second salt solution is 2.00mol/L, namely a mixed solution B;
step two: pumping the mixed solution A into a reaction kettle at a rate of 4L/h under the atmosphere of nitrogen, and simultaneously adding a sodium hydroxide solution serving as a precipitant solution and an ammonia water solution serving as a complexing agent solution into the reaction kettle to perform a first coprecipitation reaction to obtain a precursor core part, wherein the molecular formula of the precursor core part is Ni 0.95 Mn 0.04 Y 0.01 (OH) 2 The concentration of the sodium hydroxide solution is 4mol/L, the concentration of the ammonia water solution is 4mol/L, and the technological conditions of the first coprecipitation reaction are as follows: the ammonia concentration in the reaction kettle is kept between 7.5g/L and 8g/L, the pH of the reaction is between 11.5 and 12, and the rotating speed of the reaction is 400rpm; stopping the reaction immediately after the coprecipitation reaction for 30 hours;
step three: immediately pumping the mixed solution B into a reaction kettle at the speed of 9L/h after the time of the first coprecipitation reaction is reached, and carrying out the second coprecipitation reaction to obtain a solid-liquid mixture; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the reaction kettle is kept between 7.7g/L and 8.5g/L, the pH of the reaction is between 11.2 and 11.8, and the rotating speed of the reaction is 450rpm; stopping the reaction immediately after the coprecipitation reaction for 50 hours;
step four: after the reaction is finished, the obtained precursor is subjected to solid-liquid separation, washing, drying and screening to obtain the compound with the chemical formula of Ni 0.85 Mn 0.14 Y 0.01 (OH) 2 Is a cobalt-free precursor of (a);
step five: and (3) mixing the precursor obtained in the step (IV) with lithium hydroxide according to a molar ratio of 1:1.07, wherein the sintering condition is that the mixture is sintered for 2 hours at 600 ℃ to 750 ℃ in oxygen atmosphere, then sintered for 10 hours at 800 ℃ after two low-temperature sections of 2 hours at the temperature of 3 ℃/min, and then crushed, crushed and sieved.
Step six: mixing the positive electrode material obtained in the step five with H 3 BO 3 、NH 4 H 2 PO 4 Uniformly mixing, wherein B accounts for 0.1 percent of the mass of the anode material, and the molar ratio of P to B is 1: and 1, performing secondary sintering under the condition of 300 ℃ sintering for 6 hours in an oxygen atmosphere, wherein the heating rate is 3 ℃/min, and sieving after cooling to obtain the cobalt-free anode material.
Physical and electrical property evaluation of the precursor and the cathode materials in examples and comparative examples
(1) Porosity and energy spectrum analysis
And analyzing the cobalt-free precursor of the obtained porous core-shell structure by using an argon ion profiler, bombarding the surface or the section of the material sample by using an argon ion beam to obtain a flat and precise polished section and a flat sample, and completing observation and analysis of microscopic features of the internal structure of the sample by matching with a Scanning Electron Microscope (SEM) to obtain a section electron microscope image of the sample. Converting an Image into an 8-bit format through Image J software, framing particles to be measured on the Image by using a rectangular frame, and clicking Image/crop to remove redundant parts in the Image; copying an original picture by Image/duplicate, then clicking the copied picture by Image/Adjust/Threshold, defaulting Default and Red to avoid error introduced by Threshold adjustment, checking Dark background, and clicking Apply; filling holes in the process/bin/Fill holes, and dividing the process/bin watered into adhesion particles; clicking target particles by using a tool magic wand as the ROI and adding the ROI to a particle manager; then, the original image is called, the showall in the ROI Manager is re-checked, and the target outline established in the copied image is identified in the original image; the upper and lower thresholds of the Image/Adjust/Threshold are not moved, default defaults algorithm is adopted, dark background is checked, and Apply is clicked, namely the Threshold extraction hole is carried out on the original Image; the test is clicked in the ROI Manager by the threshold effect of the edition/invart conversion artwork, and the Result list directly shows the particle profile porosity results, which are shown in table 1. Fig. 1 is a cross-sectional electron microscopic view of example 3, and fig. 2 is a cross-sectional electron microscopic view of comparative example 3.
The cobalt-free cathode material with the porous core-shell structure obtained in example 3 was characterized by using an argon ion profiler and energy spectrum analysis, and the change of the element content in the cobalt-free cathode material was obtained, and is shown in fig. 6.
(2) Electrical performance testing
Weighing 3% super-P, 2% KS-6, 3% PVDF, 92% positive electrode material and 4g NMP under the conditions of constant temperature and constant humidity of 21-25 ℃ and humidity less than or equal to 10%, mixing, stirring at 3500rpm for 3 min, staying for 1 min, and adding the rest NMP (25 g) was stirred at 3500rpm for 3 minutes, and the stirring was terminated. And (3) uniformly coating the mixed slurry on 35 cm-7.5 cm aluminum foil in a manual drawing and coating mode, ensuring uniform thickness, and placing the coated pole piece in a 100 ℃ blast oven for drying for 30 minutes in a horizontal state. After the dried pole piece is taken out, a positive pole plate cutter is used for cutting the pole piece into a size with the length of 25cm and 7.5cm, and then blank aluminum foils with the same size are independently cut; according to 3.2g/cm 3 Rolling the pole piece, punching the rolled pole piece into a positive pole piece by using a punching die, and baking for 8 hours in a vacuum oven at 100+/-3 ℃ and-0.1 MPa; the diaphragm is aligned and folded into four layers, a button cell diaphragm is punched out by a punching die, and the button cell diaphragm is baked in a blast oven at 60 ℃ for 2 to 3 hours; and assembling and sealing the cathode shell, the gasket, the lithium sheet, 2 drops of electrolyte, the diaphragm, 1 drop of electrolyte, the anode sheet and the cathode shell in sequence in a glove box, and completing the manufacturing of the 2016-type button cell.
Capacity: after the button cell is prepared, the button cell is subjected to formation, the formation voltage is 3.0-4.3V, the formation rate is 0.1C, and the charging specific capacity of 0.1C, the discharging specific capacity of 0.1C and the first efficiency are respectively obtained, and the results are shown in Table 1.
Cycle performance: the obtained positive electrode material is manufactured into a soft-package battery under the conditions of constant temperature and constant humidity at the normal temperature of 21-25 ℃ and the humidity of less than or equal to 10 percent, the soft-package battery is formed after the preparation is finished, and the formed battery is subjected to high-temperature cycle test in a high-temperature detection cabinet: the high temperature is 45 ℃, the charging rate is 1C rate and the discharging rate is 1C rate in the voltage range of 2.75-4.2V, and the result is shown in figure 3.
Rate capability: and preparing the obtained positive electrode material into a soft-package battery, carrying out formation after the preparation of the soft-package battery is finished, carrying out rate performance test on the battery after formation in a normal temperature detection cabinet, carrying out charging rate of 1C at normal temperature of 23 ℃, respectively carrying out discharging rate of 1C, 3C and 5C, and calculating discharge capacity retention rates of different rates, wherein the results are shown in Table 2 and the graphs shown in figures 4 and 5.
TABLE 1 detection results of precursor porosity and positive electrode material buckling property
The data of comparative example 1 show that the sintering temperature needs to be changed in order to ensure the formation of gradient and the electrical properties of the material by doping during sintering, and that the sintering is multi-step and the energy consumption is high. Comparative example 1 also had poorer buckling performance and lower capacity and initial efficiency than the examples.
As can be seen from table 1, the cobalt-free precursor of the porous core-shell structure can be obtained by strictly controlling the reaction molar ratio, ammonia concentration, pH, rotation speed and D50 in each link of the precursor coprecipitation reaction. In the comparative example, however, the reaction was not performed in accordance with the above-described strict control of each index, and a precursor having such morphology could not be obtained. The small porosity is not beneficial to the rapid deintercalation of lithium ions, and the charge and discharge performance of the material in a lithium ion battery is limited to a great extent. The porous structure of the positive electrode material prepared by the method greatly shortens the diffusion path of lithium ions, improves the deintercalation rate of the positive electrode material and strengthens the diffusion kinetics of the lithium ions. According to the data of the examples and the comparative examples, the positive electrode material with relatively large porosity and high discharge specific capacity corresponding to the precursor with gradient distribution of doping elements is obtained.
TABLE 2 discharge capacity at different rates and retention
As can be seen from table 2 and fig. 4 and 5, the cathode materials prepared in example 3 and example 4 have relatively high discharge capacity and capacity retention rate compared to the cathode material prepared in comparative example 3, indicating that the gradient distribution of doping elements leads to improvement of rate performance. Whereas example 4 slightly decreased the discharge capacity and the capacity retention rate compared with example 3. Therefore, the doping amount and the porosity of doping elements in the cobalt-free cathode material with the porous core-shell structure need to be strictly controlled; the doping amount is more, the porosity is small, the resistance is improved, and the rate performance is poor; the doping amount is less, the contact area of the positive electrode material with larger porosity and the electrolyte is increased, and the multiplying power and the cycle performance of the material are not facilitated.
From fig. 3, it can be derived that: the cycle retention rates of the soft-packed batteries prepared from the cobalt-free cathode materials with the porous core-shell structures obtained in examples 1 to 4 are all better than those of the soft-packed batteries prepared from the conventional cobalt-free cathode materials of comparative examples 1 to 3. On the premise of not changing the total metal composition of the material, the internal elements of the material are distributed in a changing concentration, the nickel content of the material is gradually reduced from the inside to the outside, and the manganese content and the doping elements are gradually increased. The concentration distribution material effectively improves the cycle life and the safety of the battery.
From fig. 6, it can be seen that by performing EDS characterization analysis on the cross section of the cathode material microsphere, the Ni content of the material tends to rise and then fall from the leftmost end to the rightmost end of the cross section, and the Mn and Y contents tend to fall and then rise. This is the same as the elemental distribution content during precursor doping, i.e. the material internal composition content does not tend to be uniformly distributed after sintering.
It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. It should be noted that modifications and creations can be made by those skilled in the art without departing from the principle of the present invention, and the modifications and creations should also be regarded as the protection scope of the present invention.
Claims (8)
1. The preparation method of the cobalt-free cathode material with the porous core-shell structure is characterized by comprising the following steps of:
step one: preparing a mixed solution A containing nickel and manganese, wherein the molar ratio of nickel ions to manganese ions in the mixed solution A is (85-95): (5-15), wherein the sum of the concentration of nickel ions and manganese ions in the mixed solution A is 2.00 mol/L-4.00 mol/L; pumping the mixed solution A into a first reaction kettle at a rate of 2.5L/h-5L/h under the atmosphere of protective gas, and simultaneously adding a precipitant solution and a complexing agent solution into the first reaction kettle to perform a first coprecipitation reaction to obtain a precursor core part, wherein the molecular formula of the precursor core part is Ni a Mn b (OH) 2 Wherein a is more than or equal to 0.8 and less than or equal to 0.95, b is more than or equal to 0.05 and less than or equal to 0.2; the concentration of the precipitant solution is 2 mol/L-4 mol/L, the complexing agent solution is 1 mol/L-4 mol/L ammonia water solution, and the technological conditions of the first coprecipitation reaction are thatThe method comprises the following steps: the ammonia concentration in the first reaction kettle is kept between 4g/L and 12g/L, the temperature is controlled between 40 ℃ and 70 ℃, the pH of the reaction is between 10.5 and 13, and the rotating speed of the reaction is between 450rpm and 500rpm; stopping the reaction when the nucleation D50 grows to 2.30-4.0 mu m in the first stage;
step two: preparing a mixed solution B containing nickel, manganese and R, wherein the molar ratio of nickel ions, manganese ions and R ions in the mixed solution B is (80-85): (10-20): (0.5-1.5), wherein the sum of the concentrations of nickel ions, manganese ions and R ions in the mixed solution B is 2.00 mol/L-4.00 mol/L; overflowing the inner core which is reacted in the first step and reaches the target particle size from a first reaction kettle, pumping the inner core into a second reaction kettle at the rate of 9-12L/h, simultaneously adding a precipitant solution and a complexing agent solution into the second reaction kettle, wherein the concentration of the precipitant solution is 2-4 mol/L, the concentration of the complexing agent solution is 1-4 mol/L of ammonia water solution, and slowly adding the mixed solution B to perform secondary coprecipitation; the process conditions of the second coprecipitation reaction are as follows: the ammonia concentration in the second reaction kettle is kept between 5g/L and 15g/L, the pH of the reaction is between 10 and 12, and the rotating speed of the reaction is between 480 and 550rpm; stopping the reaction when the integral D50 of the inner core and the inner shell layer in the second reaction kettle is as long as 6.5-8.0 mu m;
step three: preparing a mixed solution C containing nickel, manganese and R, dissolving nickel salt, manganese salt and R salt powder in pure water, and preparing the mixed solution C with the total concentration of 2.00mol/L to 4.00mol/L according to the molar ratio of (70-80): (15-30): (1.5-3); overflowing the precursor inner core and the precursor inner shell which reach the target particle size in the second step into a third reaction kettle at the rate of 12-15L/h through a second reaction kettle, and simultaneously adding a precipitant solution, a complexing agent solution and a mixed solution C into the third reaction kettle for a third coprecipitation reaction, wherein the concentration of the precipitant solution is 2-4 mol/L, and the concentration of the complexing agent solution is 1-4 mol/L of ammonia water solution; the process conditions of the third coprecipitation reaction are as follows: the ammonia concentration in the third reaction kettle is kept between 7g/L and 15g/L, the pH of the reaction is between 10.5 and 12, the reaction time is between 50 and 60 hours, and the rotating speed of the reaction is between 550 and 600rpm; stopping the reaction when the final grain size grows to 8.5-10.0 mu m;
step four: carrying out solid-liquid separation, washing, drying and screening on the precursor prepared in the step three to obtain a cobalt-free precursor with a porous core-shell structure;
step five: uniformly mixing the precursor obtained in the fourth step with one or two of lithium carbonate and lithium hydroxide, and sintering at a high temperature of 650-950 ℃ for 10-15 h; the sintering atmosphere is oxygen, air with moisture and carbon dioxide removed or a mixed gas atmosphere of the oxygen, the air with moisture and the carbon dioxide removed; the temperature rising rate is 2-8 ℃/min; crushing, crushing and sieving after cooling;
step six: uniformly mixing the anode material matrix obtained in the step five with a source B and a source P, and then performing secondary sintering at 300-550 ℃ for 4-8 hours; the sintering atmosphere is oxygen, air with moisture and carbon dioxide removed or a mixed gas atmosphere of the oxygen, the air with moisture and the carbon dioxide removed; the temperature rising rate is 2-8 ℃/min; and cooling and sieving to obtain the cobalt-free anode material with the porous core-shell structure.
2. The method for preparing the cobalt-free cathode material with the porous core-shell structure according to claim 1, wherein the mixed solution A, the mixed solution B and the mixed solution C are one or more of nitrate, sulfate, chloride and acetate solutions of nickel and manganese.
3. The method for preparing a cobalt-free cathode material with a porous core-shell structure according to claim 1, wherein the precipitant solution is one or more of potassium hydroxide, potassium carbonate, sodium hydroxide and sodium carbonate aqueous solution.
4. The method for preparing a cobalt-free cathode material with a porous core-shell structure according to claim 1, wherein in the fifth step, the molar ratio of the total mole of metals in the precursor to the mole of lithium element is 1:1.04-1.1.
5. The method for preparing a cobalt-free cathode material with a porous core-shell structure according to claim 1, wherein R is one or more of Al, Y, nb, ce, ti, ta.
6. A plurality of as claimed in claim 1The preparation method of the cobalt-free cathode material with the pore core-shell structure is characterized in that the source B is H 3 BO 3 The P source is NH 4 H 2 PO 4 。
7. The cobalt-free anode material with the porous core-shell structure, which is obtained by adopting the preparation method of the cobalt-free anode material with the porous core-shell structure, is disclosed in claim 5.
8. The cobalt-free cathode material of claim 7, wherein the cobalt-free cathode material of porous core-shell structure has a chemical composition formula ofWherein a is more than or equal to 1.04 and less than or equal to 1.1,0.8, x is more than or equal to 0.95,0.005 and y is more than or equal to 0.03,0.0005 and e is more than or equal to 0.01,0.0005 and f is more than or equal to 0.01.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410038059.3A CN117558904A (en) | 2024-01-11 | 2024-01-11 | Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410038059.3A CN117558904A (en) | 2024-01-11 | 2024-01-11 | Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117558904A true CN117558904A (en) | 2024-02-13 |
Family
ID=89813078
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410038059.3A Pending CN117558904A (en) | 2024-01-11 | 2024-01-11 | Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117558904A (en) |
Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180013129A1 (en) * | 2015-06-17 | 2018-01-11 | Lg Chem, Ltd. | Positive electrode active material for secondary battery, method of preparing the same, and secondary battery including the positive electrode active material |
| WO2018143753A1 (en) * | 2017-02-06 | 2018-08-09 | 주식회사 엘지화학 | Positive electrode active material for secondary battery, method for preparing same and lithium secondary battery comprising same |
| CN108899502A (en) * | 2018-06-29 | 2018-11-27 | 格林美（无锡）能源材料有限公司 | A kind of high capacity nickle cobalt lithium manganate base composite positive pole and preparation method thereof |
| CN110422889A (en) * | 2019-06-24 | 2019-11-08 | 当升科技(常州)新材料有限公司 | Precursor of lithium ionic cell positive material and anode material for lithium-ion batteries and respective preparation method and lithium ion battery |
| CN111628149A (en) * | 2020-06-02 | 2020-09-04 | 格林美股份有限公司 | Gradient-doped high-nickel ternary positive electrode material and preparation method thereof |
| CN111634958A (en) * | 2020-06-02 | 2020-09-08 | 格林美股份有限公司 | Precursor for lithium battery, lithium battery positive electrode material and preparation method of lithium battery positive electrode material |
| CN111653742A (en) * | 2020-05-11 | 2020-09-11 | 格林美（无锡）能源材料有限公司 | Lithium ion battery anode material with full-gradient concentration distribution and preparation method thereof |
| CN111916723A (en) * | 2020-07-14 | 2020-11-10 | 蜂巢能源科技有限公司 | Gradient-doped cobalt-free cathode material, preparation method thereof, lithium ion battery cathode and lithium battery |
| CN112993259A (en) * | 2021-05-12 | 2021-06-18 | 蜂巢能源科技有限公司 | Coated ternary cathode material, preparation method thereof and lithium ion battery |
| WO2021238051A1 (en) * | 2020-05-25 | 2021-12-02 | 蜂巢能源科技有限公司 | Cobalt-free positive electrode material, preparation method therefor, and lithium-ion battery |
| CN113889615A (en) * | 2021-08-30 | 2022-01-04 | 中南大学 | Cobalt-free high-nickel ternary concentration gradient core-shell structure lithium ion battery cathode material and preparation method thereof |
| CN114551837A (en) * | 2022-03-25 | 2022-05-27 | 中南大学 | Quick-charging type cobalt-free high-nickel ternary concentration gradient core-shell structure lithium ion battery positive electrode material and preparation method thereof |
| CN115745028A (en) * | 2022-12-15 | 2023-03-07 | 广东佳纳能源科技有限公司 | Binary material precursor, preparation method thereof and positive electrode material |
| CN115959717A (en) * | 2022-12-21 | 2023-04-14 | 北京工业大学 | Preparation of cobalt-free high-nickel layered oxide positive electrode material with full concentration gradient and adjustable gradient slope |
| CN116314731A (en) * | 2023-05-24 | 2023-06-23 | 浙江帕瓦新能源股份有限公司 | Sodium ion battery anode material, precursor thereof, preparation method and application |
| WO2023185278A1 (en) * | 2022-03-30 | 2023-10-05 | 宁波容百新能源科技股份有限公司 | Hollow porous positive electrode material having concentration gradient and preparation method therefor |
| WO2023193826A1 (en) * | 2022-06-30 | 2023-10-12 | 北京当升材料科技股份有限公司 | Positive electrode material, preparation method therefor, and application thereof |
| CN117105283A (en) * | 2023-08-23 | 2023-11-24 | 荆门市格林美新材料有限公司 | Core-shell structured positive electrode precursor material and preparation method and application thereof |
| CN117352706A (en) * | 2023-12-04 | 2024-01-05 | 宁波容百新能源科技股份有限公司 | Positive electrode material, preparation method thereof and lithium ion battery |
-
2024
- 2024-01-11 CN CN202410038059.3A patent/CN117558904A/en active Pending
Patent Citations (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20180013129A1 (en) * | 2015-06-17 | 2018-01-11 | Lg Chem, Ltd. | Positive electrode active material for secondary battery, method of preparing the same, and secondary battery including the positive electrode active material |
| WO2018143753A1 (en) * | 2017-02-06 | 2018-08-09 | 주식회사 엘지화학 | Positive electrode active material for secondary battery, method for preparing same and lithium secondary battery comprising same |
| CN108899502A (en) * | 2018-06-29 | 2018-11-27 | 格林美（无锡）能源材料有限公司 | A kind of high capacity nickle cobalt lithium manganate base composite positive pole and preparation method thereof |
| CN110422889A (en) * | 2019-06-24 | 2019-11-08 | 当升科技(常州)新材料有限公司 | Precursor of lithium ionic cell positive material and anode material for lithium-ion batteries and respective preparation method and lithium ion battery |
| CN111653742A (en) * | 2020-05-11 | 2020-09-11 | 格林美（无锡）能源材料有限公司 | Lithium ion battery anode material with full-gradient concentration distribution and preparation method thereof |
| WO2021238051A1 (en) * | 2020-05-25 | 2021-12-02 | 蜂巢能源科技有限公司 | Cobalt-free positive electrode material, preparation method therefor, and lithium-ion battery |
| CN111628149A (en) * | 2020-06-02 | 2020-09-04 | 格林美股份有限公司 | Gradient-doped high-nickel ternary positive electrode material and preparation method thereof |
| CN111634958A (en) * | 2020-06-02 | 2020-09-08 | 格林美股份有限公司 | Precursor for lithium battery, lithium battery positive electrode material and preparation method of lithium battery positive electrode material |
| CN111916723A (en) * | 2020-07-14 | 2020-11-10 | 蜂巢能源科技有限公司 | Gradient-doped cobalt-free cathode material, preparation method thereof, lithium ion battery cathode and lithium battery |
| CN112993259A (en) * | 2021-05-12 | 2021-06-18 | 蜂巢能源科技有限公司 | Coated ternary cathode material, preparation method thereof and lithium ion battery |
| CN113889615A (en) * | 2021-08-30 | 2022-01-04 | 中南大学 | Cobalt-free high-nickel ternary concentration gradient core-shell structure lithium ion battery cathode material and preparation method thereof |
| CN114551837A (en) * | 2022-03-25 | 2022-05-27 | 中南大学 | Quick-charging type cobalt-free high-nickel ternary concentration gradient core-shell structure lithium ion battery positive electrode material and preparation method thereof |
| WO2023185278A1 (en) * | 2022-03-30 | 2023-10-05 | 宁波容百新能源科技股份有限公司 | Hollow porous positive electrode material having concentration gradient and preparation method therefor |
| WO2023193826A1 (en) * | 2022-06-30 | 2023-10-12 | 北京当升材料科技股份有限公司 | Positive electrode material, preparation method therefor, and application thereof |
| CN115745028A (en) * | 2022-12-15 | 2023-03-07 | 广东佳纳能源科技有限公司 | Binary material precursor, preparation method thereof and positive electrode material |
| CN115959717A (en) * | 2022-12-21 | 2023-04-14 | 北京工业大学 | Preparation of cobalt-free high-nickel layered oxide positive electrode material with full concentration gradient and adjustable gradient slope |
| CN116314731A (en) * | 2023-05-24 | 2023-06-23 | 浙江帕瓦新能源股份有限公司 | Sodium ion battery anode material, precursor thereof, preparation method and application |
| CN117105283A (en) * | 2023-08-23 | 2023-11-24 | 荆门市格林美新材料有限公司 | Core-shell structured positive electrode precursor material and preparation method and application thereof |
| CN117352706A (en) * | 2023-12-04 | 2024-01-05 | 宁波容百新能源科技股份有限公司 | Positive electrode material, preparation method thereof and lithium ion battery |
Non-Patent Citations (2)
| Title |
|---|
| 张永政: "梯度型高镍NCM三元材料的铌掺杂研究", 中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑, no. 03, 15 March 2022 (2022-03-15), pages 015 - 600 * |
| 李伟权;刘更好;汪乾;林弘嘉;阮丁山;: "内多孔型LiNi_(0.5)Co_(0.2)Mn_(0.3)O_2正极材料的制备及性能", 电源技术, no. 07, 20 July 2020 (2020-07-20), pages 942 - 944 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11394024B2 (en) | Nickel-cobalt-manganese complex hydroxide particles and method for producing same, positive electrode active material for nonaqueous electrolyte secondary battery and method for producing same, and nonaqueous electrolyte secondary battery | |
| US10038189B2 (en) | Transition metal composite hydroxide capable of serving as precursor of positive electrode active material for nonaqueous electrolyte secondary batteries | |
| US11482703B2 (en) | Positive-electrode active material precursor for nonaqueous electrolyte secondary battery and method for manufacturing positive-electrode active material precursor for nonaqueous electrolyte secondary battery | |
| CN111916727B (en) | Dual-ion wet-doped ternary high-nickel cathode material and preparation method thereof | |
| CN110867573A (en) | Ternary cathode material, preparation method thereof, lithium ion battery and electric automobile | |
| CN104136376A (en) | Nickel compound hydroxide and method for producing same, positive pole active substance for nonaqueous electrolyte secondary cell and method for producing same, and nonaqueous electrolyte secondary cell | |
| US11949102B2 (en) | Positive electrode active material precursor for nonaqueous electrolyte secondary battery and method for manufacturing positive electrode active material precursor for nonaqueous electrolyte secondary battery | |
| JPWO2017104688A1 (en) | Positive electrode active material for lithium secondary battery, method of producing precursor of positive electrode active material, method of producing positive electrode active material, positive electrode for lithium secondary battery, and lithium secondary battery | |
| CN114665090A (en) | Method for preparing large-particle-size single crystal ternary cathode material at low temperature in one step | |
| CN110854385A (en) | Ternary cathode material with different particle sizes and preparation method thereof | |
| CN110863245A (en) | Ternary cathode material, preparation method thereof, lithium ion battery and electric automobile | |
| CN113113590B (en) | Single crystal anode material with core-shell structure and preparation method thereof | |
| CN109216678B (en) | Preparation method of nickel-rich ternary material coated with lithium cobalt phosphate | |
| CN114645314A (en) | Preparation method of single crystal morphology ternary cathode material | |
| WO2024082929A1 (en) | Lithium-nickel composite oxide positive electrode material and preparation method therefor | |
| CN116864687A (en) | Positive electrode material, preparation method thereof and lithium ion battery | |
| US20230268495A1 (en) | Method of producing nickel-containing hydroxide, method of producing positive electrode active material for lithium ion secondary battery, positive electrode active material for lithium ion secondary battery, and lithium ion secondary battery | |
| CN117558904A (en) | Cobalt-free positive electrode material with porous core-shell structure and preparation method thereof | |
| JP2019169412A (en) | Positive electrode active material for high-strength lithium ion secondary battery, and lithium ion secondary battery arranged by use thereof | |
| CN115084457A (en) | High-compaction long-life ternary cathode material and preparation method thereof | |
| CN113707873A (en) | Lithium ion battery positive electrode material using eutectic lithium salt and preparation method thereof | |
| WO2023228957A1 (en) | Positive electrode active material for lithium-ion secondary battery and method for producing same | |
| WO2023228956A1 (en) | Positive electrode active material for lithium ion secondary battery, and method for manufacturing positive electrode active material for lithium ion secondary battery | |
| CN116750802A (en) | Preparation method and application of layered oxide sodium ion battery positive electrode material | |
| CN117164021A (en) | Tungsten element doped cobalt-free positive electrode precursor, and preparation method and application 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 |