CN114566625A - Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof - Google Patents
Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof Download PDFInfo
- Publication number
- CN114566625A CN114566625A CN202210204581.5A CN202210204581A CN114566625A CN 114566625 A CN114566625 A CN 114566625A CN 202210204581 A CN202210204581 A CN 202210204581A CN 114566625 A CN114566625 A CN 114566625A
- Authority
- CN
- China
- Prior art keywords
- lithium
- positive electrode
- rich manganese
- electrode material
- based positive
- 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.)
- Granted
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
-
- 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
- C01G53/42—Nickelates containing alkali metals, e.g. LiNiO2
- C01G53/44—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M2220/00—Batteries for particular applications
- H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
-
- 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)
- Composite Materials (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a lithium-rich manganese-based positive electrode material with low pressure drop performance, and a preparation method and application thereof, wherein the chemical formula of the lithium-rich manganese-based positive electrode material is Li1.2Mn0.54NixCo(0.26－x)O2X is more than or equal to 0.13 and less than or equal to 0.26, and the coating layer is Li3NbO4The coating amount is 1-5% of the mass of the lithium-rich manganese-based positive electrode material. The invention adjusts nickel element and cobalt elementThe proportion of the element is in a specific proportion range, the anode material which is excellent in the aspect of inhibiting voltage attenuation is prepared by adopting a sol-gel method, under the test conditions of a voltage range of 2.0V-4.8V and 0.1C charge and discharge current, the average voltage attenuation after 50 weeks of circulation is optimally represented by 120-130mV, the anode material has excellent low voltage drop performance, and meanwhile, the anode material passes through Li3NbO4The low-pressure drop performance of the coated lithium-rich manganese-based positive electrode material is better, and the commercialization process of the lithium-rich manganese-based positive electrode material is promoted.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a lithium-rich manganese-based positive electrode material with low pressure drop performance and a preparation method and application thereof.
Background
Under the background of global warming, aggravation of greenhouse effect, energy shortage, vigorous driving of national policies and enhancement of environmental awareness of people, new energy automobiles become a necessary trend for development of the current automobile industry. The development of an energy storage system which is one of the most core technologies of the electric automobile is inseparable with the promotion of the new energy automobile industry. The best energy storage device known at present is a lithium ion battery, and compared with other energy storage systems, the lithium ion battery has the advantages of high energy density, high average output voltage, high output power, small self-discharge, high charging efficiency and the like, and is widely applied to the fields of portable equipment, electric automobiles, hybrid electric vehicles and the like. However, lithium ion batteries still need further improvement in rate performance, cycle performance, safety performance, and the like. Compared with the negative electrode material of the lithium ion battery, the positive electrode material has lower specific discharge capacity, and the positive electrode material contains a large amount of transition metal and lithium to directly control the cost of the lithium ion battery, and is also the main reason for limiting the further improvement of the performance of the lithium ion battery.
In recent years, lithium-rich manganese-based positive electrode material (xLiMO)2·(1-x)Li2MnO3) By virtue of high energy density, high specific capacity, low cost,The lithium ion battery anode material has the advantages of good safety performance and the like, becomes a hotspot of research, and is considered to be one of the lithium ion battery anode materials with great application prospects. However, the lithium-rich manganese-based cathode material is not widely applied in a commercial way at present, one of the main reasons is that the problem of voltage attenuation occurs in the circulation process, and the gradual reduction of the average discharge voltage leads to the change of the output voltage, power and energy of the battery, thereby directly restricting the development of the high-capacity layered lithium-rich manganese-based cathode material. The high capacity of the lithium-rich manganese-based cathode material is derived from the additional utilization of lattice oxygen, but lithium oxygen vacancies, lithium tetrahedral sites, transition metal migration, edge dislocations, stacking faults, local stress and the like are generated in the crystal structure in the process of activating the oxygen activity of the lattice, the formation of the defects causes the first irreversible structural transformation and the voltage attenuation in the cycle process, and although the formation of the defects can be inhibited by means of surface modification, element doping and the like so as to maintain the structural order, the intrinsic voltage attenuation of the material is unavoidable. The voltage attenuation is related to the metastability, the reversibility and the voltage recoverability of the structure, and the calculation is performed by combining the synchrotron radiation X-ray diffraction, the neutron diffraction, the electron diffraction and the first principle, so that a possible effective way is found for solving the voltage attenuation problem of the lithium-rich manganese-based anode material, the voltage attenuation of the lithium-rich manganese-based anode material can be effectively inhibited, and the commercialization process of the lithium-rich manganese-based anode material is promoted.
Disclosure of Invention
The invention aims to: aiming at the existing problems, the invention provides the lithium-rich manganese-based positive electrode material with low pressure drop performance, and the preparation method and the application thereof.
The technical scheme adopted by the invention is as follows: the lithium-rich manganese-based anode material with low pressure drop performance has a chemical formula of Li1.2Mn0.54NixCo(0.26-x)O2Wherein x is more than or equal to 0.13 and less than or equal to 0.26.
In the present invention, it is concluded from the simultaneous experiments that the molar ratio of nickel and cobalt is required to be within the above-mentioned range, and that an excessively high or low molar ratio of nickel and cobalt may cause the pressure drop property of the positive electrode material to be difficult to achieve the low pressure drop property claimed in the present invention.
Preferably, the chemical formula of the lithium-rich manganese-based cathode material is Li1.2Mn0.54Ni0.23O2。
In the invention, in order to further improve the low pressure drop performance of the lithium-rich manganese-based cathode material, the surface of the lithium-rich manganese-based cathode material is coated with Li3NbO4And (3) a layer. Li3NbO4The coating prevents the corrosion of the electrolyte to the material, reduces the occurrence of side reaction of the electrolyte, and promotes the diffusion of lithium ions and the conduction of electrons, in addition, Nb diffuses into the surface crystal lattice of the material in the calcining process to form a stronger Nb-O bond, and inhibits the loss of surface crystal lattice oxygen of the lithium-rich manganese-based anode material in the circulating process, thereby stabilizing the crystal structure of the material and improving the circulating performance of the material.
Further, the Li3NbO4The coating amount of the layer is 1-5% of the mass of the lithium-rich manganese-based positive electrode material.
The invention also discloses a preparation method of the lithium-rich manganese-based positive electrode material with low pressure drop performance, which comprises the following steps:
A. dissolving soluble lithium salt, soluble nickel salt, soluble cobalt salt and soluble manganese salt in a designed proportion into deionized water to obtain a mixed salt solution, adding a citric acid solution into the mixed salt solution, uniformly stirring, and adding a pH value regulator to regulate the pH value of the solution;
B. and C, heating and evaporating the mixed salt solution obtained in the step A at constant temperature, and then drying, calcining and cooling to obtain the lithium-rich manganese-based positive electrode material.
Further, the molar concentration ratio of the citric acid solution to the mixed salt solution is 1: 1; the molar concentration of the mixed salt solution is 2 mol/L; the pH value of the solution is adjusted to 7.0-7.5.
Further, in the step B, the constant temperature heating temperature is 80 ℃, the drying mode adopts vacuum drying, the drying time is 24-36h, and the drying temperature is 80 ℃.
Further, weighing a designed amount of the lithium-rich manganese-based positive electrode material obtained in the step B, dissolving the lithium-rich manganese-based positive electrode material in an organic solvent to form a solution, weighing a designed amount of soluble niobium salt and soluble lithium salt, adding the soluble niobium salt and the soluble lithium salt into the solution, stirring and mixing, stirring at a constant temperature of 50-60 ℃, evaporating to dryness, and calcining to obtain Li3NbO4And (3) a coated lithium-rich manganese-based positive electrode material.
Further, during calcination, the temperature is raised to 450-550 ℃ at the temperature raising rate of 4-6 ℃/min, and after heat preservation is carried out for 3-7h, the Li is obtained by furnace cooling3NbO4And (3) a coated lithium-rich manganese-based positive electrode material.
The invention also comprises a lithium ion battery which comprises the lithium ion battery anode material, wherein the lithium ion battery anode material is the lithium-rich manganese-based anode material with the low pressure drop performance.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
1. according to the invention, by adjusting the proportion of nickel element and cobalt element, under a specific proportion range, the cathode material which is excellent in voltage attenuation inhibition is prepared by adopting a sol-gel method, under the test conditions of a voltage interval of 2.0V-4.8V and 0.1C (1C is 250mAh g-1) charge-discharge current, the average voltage attenuation is optimally expressed as 120-130mV after 50-week circulation, the cathode material has excellent low voltage drop performance, and the commercialization process of the lithium-rich manganese-based cathode material is promoted;
2. the invention is prepared by Li3NbO4The low-pressure drop performance of the lithium-rich manganese-based positive electrode material is better due to the coating, and the commercialization process of the lithium-rich manganese-based positive electrode material is further promoted.
Drawings
Fig. 1 shows the voltage range of 2.0V to 4.8V and 0.1C (1C: 250mAh g) of CR2025 coin cells assembled with the lithium-rich manganese-based positive electrode materials prepared in examples 1 to 4-1) A cycle performance curve under magnification;
fig. 2 shows the voltage range of 2.0V to 4.8V and 0.1C (1C ═ C) for CR2025 coin cells assembled with the lithium-rich manganese-based positive electrode materials prepared in examples 1 to 4250mAh·g-1) Average voltage change curve under multiplying power;
FIGS. 3-6 are Scanning Electron Microscope (SEM) images of lithium-rich manganese-based positive electrode materials of different ratios of nickel and cobalt prepared in examples 1-4;
FIG. 7 is an X-ray diffraction (XRD) normalized spectrum of lithium-rich manganese-based cathode materials of different ratios of nickel and cobalt prepared in examples 1-4;
FIG. 8 shows different Li prepared in example 53NbO4A first-cycle charge-discharge curve of the lithium-rich manganese-based positive electrode material with the coating amount;
FIG. 9 shows different Li's prepared in example 53NbO4First cycle capacity differential curve of the coated amount of lithium-rich manganese-based positive electrode material.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
A preparation method of a lithium-rich manganese-based positive electrode material with low pressure drop performance comprises the following steps:
s1, adding CH3COOHLi·2H2O(AR 99.0％)、Mn(CH3COOH)2·4H2O(AR 99.0％)、Ni(CH3COOH)2·4H2O (AR 99.0%) and Co (CH)3COOH)2·4H2O (AR 99.0%) in a molar ratio Li: mn: ni: co 1.2: 0.54: 0.13: 0.13 is mixed with deionized water to prepare the Mn, Ni and Co ions with the total concentration of 2 mol.L-1Adding citric acid solution with the same volume and the same molar concentration into the mixed salt solution, uniformly stirring, and adding ammonia water to adjust the pH value of the solution to about 7;
s2, placing the solution obtained in the step S1 on a heatable magnetic stirrer, stirring at a constant temperature of 80 ℃ until the solution is completely evaporated to dryness to obtain gel, uniformly coating the gel on the wall of a crucible, and placing the gel in a vacuum oven at 80 ℃ for drying for 24 hours;
s3, placing the dried material in a muffle furnace for calcination, heating to 450 ℃ at a speed of 5 ℃/min, preserving heat for 5h to completely remove organic matters, cooling along with the furnace, taking out and grinding for 10min, then placing the material in the muffle furnace, heating to 900 ℃ at a speed of 5 ℃/min, preserving heat for 12h, and cooling along with the furnace to obtain the lithium-rich manganese-based positive electrode material Li1.2Mn0.54Ni0.13Co0.13O2。
The obtained positive electrode material, acetylene black and polyvinylidene fluoride (PVDF) were mixed in accordance with a ratio of 8: 1: 1, adding a solvent N-methyl-2-pyrrolidone (NMP), mixing into a slurry, adjusting to a certain viscosity, uniformly coating the slurry on an aluminum foil by using a scraper, drying the aluminum foil in a 60 ℃ oven for 12 to 18 hours, drying the aluminum foil in a 120 ℃ vacuum oven for 2 to 3 hours, cutting the dried aluminum foil loaded with the slurry into small round pieces with the diameter of about 11mm by using a cutting machine as a positive electrode, using a metal lithium piece as a negative electrode, using Celgard2500 as a diaphragm, using a 1M carbonate solution as an electrolyte (wherein the solvent is a mixed solution of ethylene carbonate and dimethyl carbonate with the volume ratio of 1: 1, and the solute is LiPF6) Assembled into CR2025 button cells in an argon glove box: the assembled CR2025 button cell was tested for cycle performance at 0.1C rate using a CT2001AAlnd cell tester, defining a 1C current density of 250mAh g-1The charging and discharging voltage interval is 2.0V-4.8V, and the testing temperature is 30 ℃.
Example 2
Example 2 is the same as example 1 except that the mixed salt solution contains Mn (CH)3COOH)2·4H2O(AR 99.0％)、Ni(CH3COOH)2·4H2O (AR 99.0%) and Co (CH)3COOH)2·4H2Molar ratio of O (AR 99.0%) Mn: ni: co ═ 0.54: 0.18: 0.08 to obtain the lithium-rich manganese-based cathode material Li1.2Mn0.54Ni0.18Co0.08O2. The CR2025 coin cells were assembled in the same manner and subjected to the relevant electrochemical performance tests.
Example 3
Example 3 is the same as example 1 except that the mixed salt solution contains Mn (CH)3COOH)2·4H2O(AR 99.0％)、Ni(CH3COOH)2·4H2O (AR 99.0%) and Co (CH)3COOH)2·4H2Molar ratio of O (AR 99.0%) Mn: ni: co ═ 0.54: 0.23: 0.03 to obtain the lithium-rich manganese-based cathode material Li1.2Mn0.54Ni0.23Co0.03O2. The CR2025 coin cells were assembled in the same manner and subjected to the relevant electrochemical performance tests.
Example 4
Example 3 is the same as example 1 except that the mixed salt solution contains Mn (CH)3COOH)2·4H2O(AR 99.0％)、Ni(CH3COOH)2·4H2O (AR 99.0%) and Co (CH)3COOH)2·4H2Molar ratio of O (AR 99.0%) Mn: ni: co ═ 0.54: 0.23: 0, obtaining the lithium-rich manganese-based cathode material Li1.2Mn0.54Ni0.23O2. The same way is adopted to assemble the CR2025 button cell, and relevant electrochemical performance tests are carried out.
Example 5
A preparation method of a lithium-rich manganese-based positive electrode material with low pressure drop performance comprises the following steps:
s1, weighing 1g of Li-rich manganese-based cathode material Li prepared in example 41.2Mn0.54Ni0.23O2Placing in a beaker filled with anhydrous ethanol, and adding 1%, 3% and 5% of Li3NbO4Respectively weighing niobium ethoxide and CH according to coating mass ratio3COOHLi·2H2Mixing O (AR 99.0%) with the above solution in a beaker, stirring at room temperature for 14-18h, placing on a heatable magnetic stirrer, and stirring at constant temperature of 50 deg.C until a powdery material is obtained;
s2, calcining the powdery material obtained in the step S1 in a muffle furnace, heating to 500 ℃ at the speed of 5 ℃/min, preserving heat for 5 hours, and then cooling along with the furnace to obtain Li3NbO4Coated withA lithium-rich manganese-based positive electrode material.
Comparative example 1
Comparative example 1 is the same as example 1 except that Mn (CH) in the mixed salt solution3COOH)2·4H2O(AR 99.0％)、Ni(CH3COOH)2·4H2O (AR 99.0%) and Co (CH)3COOH)2·4H2Molar ratio of O (AR 99.0%) Mn: ni: co ═ 0.4: 0.1: 0.3, obtaining the lithium-rich manganese-based cathode material Li1.2Mn0.4Ni0.1CO0.3O2. The CR2025 coin cells were assembled in the same manner and subjected to the relevant electrochemical performance tests. The battery has a voltage range of 2.0V-4.8V and 0.1C (1C: 250 mAh.g)-1) Under the multiplying power, after circulating for 50 circles, the average discharge voltage attenuation amplitude is between 320 and 330mV, and the voltage attenuation is larger.
Test results
1. FIG. 1 shows a CR2025 coin cell assembled with the lithium-rich manganese-based positive electrode materials obtained in examples 1 to 4 as the positive electrode bulk material, at a voltage range of 2.0V to 4.8V and at 0.1C (1C: 250 mAh. g)-1) Graph of average voltage change under magnification. As can be seen from fig. 1: the four prepared materials have different voltage attenuation trends in the circulating process, and after the four prepared materials are circulated for 50 circles under the same test condition, the average voltage attenuation amplitude is gradually reduced along with the increase of the proportion of the Ni element in the materials, wherein Li with the most excellent performance1.2Mn0.54Ni0.23O2The average discharge voltage decay amplitude of the material after 50 cycles is between 120 and 130 mV. It is thus demonstrated that the lithium-rich manganese-based positive electrode materials obtained in examples 1 to 4 of the present invention are excellent in suppressing voltage drop, and within the range of the ratio specified in the present invention, the positive electrode materials are more excellent in suppressing voltage drop as the content of nickel increases.
2. FIG. 2 shows a CR2025 coin cell assembled with the lithium-rich manganese-based positive electrode materials obtained in examples 1 to 4 as a positive electrode material, at a voltage range of 2.0V to 4.8V and at 0.1C (1C: 250 mAh. g)-1) Cycle performance graph under multiplying power. As can be seen from fig. 2: under the same test conditionsAfter 50 cycles, the discharge capacity at the first cycle gradually decreased with an increase in the proportion of the Ni element in the material, but the capacity retention rate tended to gradually increase, and Li, which is excellent in suppressing the voltage drop-off, among them1.2Mn0.54Ni0.23O2The first-week discharge capacity of the material is 260mAh g-1About, after 50 cycles at a current density of 0.1C, the capacity retention rate was close to 90%. Therefore, the lithium-rich manganese-based positive electrode material prepared by the invention is excellent in capacity retention rate.
3. Fig. 3 to 6 are SEM images of the lithium-rich manganese-based positive electrode materials prepared in examples 1 to 4. As can be seen in fig. 3-6: the four prepared lithium-rich manganese-based anode materials are in random shapes, the particle size is below 500nm, the particle size is gradually increased along with the increase of the proportion of Ni element in the materials, and the increase range of the particle size is between 100nm and 200nm each time. Therefore, the lithium-rich manganese-based positive electrode material prepared by the method has small primary particle size and uniform dispersion, and is beneficial to shortening the lithium ion transmission path and improving the electrochemical performance.
4. Fig. 7 is an XRD normalized graph of the lithium-rich manganese-based positive electrode materials prepared in examples 1 to 4. As can be seen in fig. 7: XRD spectrograms of the four materials all show characteristic diffraction peaks of the layered lithium-rich manganese-based positive electrode material, and the main part of the material is represented by layered R-3m type LiCoO2Analogous alpha-NaFeO2The standard characteristic peaks of (a), weak diffraction peaks appear at 2 θ of 20 to 25 °, and both the (006) and (102) or (018) and (110) diffraction peaks can be clearly identified and clearly split, thereby indicating that the crystalline crystallinity of the material is good.
5. FIG. 8 shows different Li prepared in example 53NbO4CR2025 coin cell comprising a positive electrode material containing a coating amount of a lithium-rich manganese-based positive electrode material, wherein the coating amount is in a voltage range of 2.0V to 4.8V and at a voltage of 0.1C (1C: 250mAh g)-1) First cycle charge and discharge curve chart under multiplying power. As can be seen in fig. 8: the material is close to 256mAh g relative to the bulk material-1Specific discharge capacity of, Li3NbO4The discharge specific capacity of the coated anode material is lower and is along with Li3NbO4Increase in coating amount, of materialThe first-cycle discharge specific capacity shows a gradually decreasing trend, but the irreversible capacity of the material is reduced. Thus, Li3NbO4The coating can reduce the first cycle irreversible capacity loss of the lithium-rich manganese-based cathode material.
6. FIG. 9 shows different Li prepared in example 53NbO4CR2025 coin cell comprising a positive electrode material containing a lithium-rich manganese-based material in a coating amount, wherein the voltage range is 2.0V-4.8V and the voltage range is 0.1C (1C: 250mAh g)-1) First cycle capacity differential plot at magnification. As can be seen in fig. 9: the oxidation peaks of all materials appearing below 4.5V correspond to Ni2+→Ni3+And Ni3+→Ni4+During discharge, two reduction peaks occurring between 4.5 and 3.0V correspond to Ni4+→Ni2+、Mn4+→Mn3+Compared to the bulk material, Li3NbO4The shift in the position of the reduction peak of the coated material occurs, probably due to Li3NbO4The coating reduces the occurrence of side reactions of the electrolyte.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. The lithium-rich manganese-based positive electrode material with low pressure drop performance is characterized in that the chemical formula of the lithium-rich manganese-based positive electrode body material is Li1.2Mn0.54NixCo(0.26－x)O2Wherein x is more than or equal to 0.13 and less than or equal to 0.26.
2. The lithium-rich manganese-based positive electrode material with low pressure drop of claim 1, wherein the chemical formula of the lithium-rich manganese-based positive electrode material is Li1.2Mn0.54Ni0.23O2。
3. The lithium-rich manganese-based positive electrode material having low pressure drop properties according to claim 1 or 2,characterized in that the surface of the lithium-rich manganese-based cathode material is coated with Li3NbO4And (3) a layer.
4. The lithium-rich manganese-based positive electrode material with low pressure drop property according to claim 3, wherein said Li is3NbO4The coating amount of the layer is 1-5% of the mass of the lithium-rich manganese-based positive electrode material.
5. A method for preparing a lithium-rich manganese-based positive electrode material with low pressure drop performance according to claim 1 or 2, comprising the steps of:
A. dissolving soluble lithium salt, soluble nickel salt, soluble cobalt salt and soluble manganese salt in a designed proportion into deionized water to obtain a mixed salt solution, adding a citric acid solution into the mixed salt solution, uniformly stirring, and adding a pH value regulator to regulate the pH value of the solution;
B. and D, heating the mixed salt solution obtained in the step A at constant temperature, evaporating to dryness, and then drying, calcining and cooling to obtain the lithium-rich manganese-based positive electrode material.
6. The method according to claim 5, wherein the molar concentration ratio of the citric acid solution to the mixed salt solution is 1: 1; the molar concentration of the mixed salt solution is 2 mol/L; the pH value of the solution is adjusted to 7.0-7.5.
7. The method for preparing the lithium-rich manganese-based positive electrode material with low pressure drop performance according to claim 5, wherein in the step B, the constant temperature heating is 80 ℃, the drying mode adopts vacuum drying, the drying time is 24-36h, and the drying temperature is 80 ℃.
8. The method according to claim 5, wherein the lithium-rich manganese-based positive electrode material obtained in step B is weighed to obtain a design amount, the lithium-rich manganese-based positive electrode material is dissolved in an organic solvent to form a solution, and then the soluble manganese-based positive electrode material is weighed to obtain a design amountAdding the soluble niobium salt and the soluble lithium salt into the solution, stirring and mixing, stirring and evaporating at a constant temperature of 50-60 ℃, and calcining to obtain Li3NbO4And (3) a coated lithium-rich manganese-based positive electrode material.
9. The method as claimed in claim 8, wherein the temperature is increased to 550 ℃ at a rate of 4-6 ℃/min during the calcination, and the temperature is maintained for 3-7h, and then the Li is obtained by furnace cooling3NbO4And (3) a coated lithium-rich manganese-based positive electrode material.
10. A lithium ion battery comprises a lithium ion battery cathode material, and is characterized in that the lithium ion battery cathode material is the lithium-rich manganese-based cathode material with low pressure drop performance according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210204581.5A CN114566625B (en) | 2022-03-02 | 2022-03-02 | Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210204581.5A CN114566625B (en) | 2022-03-02 | 2022-03-02 | Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114566625A true CN114566625A (en) | 2022-05-31 |
| CN114566625B CN114566625B (en) | 2023-06-20 |
Family
ID=81717254
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210204581.5A Active CN114566625B (en) | 2022-03-02 | 2022-03-02 | Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114566625B (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20170155132A1 (en) * | 2015-11-30 | 2017-06-01 | Lg Chem, Ltd. | Surface-treated positive electrode active material for lithium secondary battery, method for preparing the same, and lithium secondary battery comprising the same |
| CN106935832A (en) * | 2017-03-31 | 2017-07-07 | 四川浩普瑞新能源材料股份有限公司 | Lithium manganese phosphate composite, its preparation method and lithium ion battery |
| CN107069026A (en) * | 2017-02-15 | 2017-08-18 | 浙江大学 | A kind of rich lithium manganese oxide anode material of effective stratiform for suppressing capacity/voltage attenuation in cyclic process and its preparation method and application |
| CN107565122A (en) * | 2017-08-07 | 2018-01-09 | 复旦大学 | A kind of preparation method of doping type nickel-cobalt lithium manganate cathode material |
| US20190157661A1 (en) * | 2016-06-15 | 2019-05-23 | Ningbo Institute Of Materials Technology And Engineering, Chinese Academy Of Sciences | Battery paste, battery electrode plate, and preparation method therefor |
| WO2020149244A1 (en) * | 2019-01-18 | 2020-07-23 | 日本化学工業株式会社 | Positive electrode active material for lithium secondary battery, method for producing same, and lithium secondary battery |
| CN112421010A (en) * | 2020-11-25 | 2021-02-26 | 惠州亿纬锂能股份有限公司 | Cathode material, preparation method thereof and lithium ion battery |
| CN113184923A (en) * | 2021-04-29 | 2021-07-30 | 昆山宝创新能源科技有限公司 | Preparation method of niobium modified lithium-rich manganese-based material, positive electrode material and lithium ion battery |
-
2022
- 2022-03-02 CN CN202210204581.5A patent/CN114566625B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20170155132A1 (en) * | 2015-11-30 | 2017-06-01 | Lg Chem, Ltd. | Surface-treated positive electrode active material for lithium secondary battery, method for preparing the same, and lithium secondary battery comprising the same |
| US20190157661A1 (en) * | 2016-06-15 | 2019-05-23 | Ningbo Institute Of Materials Technology And Engineering, Chinese Academy Of Sciences | Battery paste, battery electrode plate, and preparation method therefor |
| CN107069026A (en) * | 2017-02-15 | 2017-08-18 | 浙江大学 | A kind of rich lithium manganese oxide anode material of effective stratiform for suppressing capacity/voltage attenuation in cyclic process and its preparation method and application |
| CN106935832A (en) * | 2017-03-31 | 2017-07-07 | 四川浩普瑞新能源材料股份有限公司 | Lithium manganese phosphate composite, its preparation method and lithium ion battery |
| CN107565122A (en) * | 2017-08-07 | 2018-01-09 | 复旦大学 | A kind of preparation method of doping type nickel-cobalt lithium manganate cathode material |
| WO2020149244A1 (en) * | 2019-01-18 | 2020-07-23 | 日本化学工業株式会社 | Positive electrode active material for lithium secondary battery, method for producing same, and lithium secondary battery |
| CN112421010A (en) * | 2020-11-25 | 2021-02-26 | 惠州亿纬锂能股份有限公司 | Cathode material, preparation method thereof and lithium ion battery |
| CN113184923A (en) * | 2021-04-29 | 2021-07-30 | 昆山宝创新能源科技有限公司 | Preparation method of niobium modified lithium-rich manganese-based material, positive electrode material and lithium ion battery |
Non-Patent Citations (1)
| Title |
|---|
| XUE JIN等: "Excellent rate capability of Mg doped Li[Li0.2Ni0.13Co0.13Mn0.54]O2cathode material for lithium-ion battery", 《ELECTROCHIMICA ACTA》, pages 19 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114566625B (en) | 2023-06-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Wu et al. | Can surface modification be more effective to enhance the electrochemical performance of lithium rich materials? | |
| Li et al. | The role of yttrium content in improving electrochemical performance of layered lithium-rich cathode materials for Li-ion batteries | |
| Wu et al. | Li [Li0. 2Mn0. 54Ni0. 13Co0. 13] O2–MoO3 composite cathodes with low irreversible capacity loss for lithium ion batteries | |
| Li et al. | Effect of niobium doping on the microstructure and electrochemical properties of lithium-rich layered Li [Li 0.2 Ni 0.2 Mn 0.6] O 2 as cathode materials for lithium ion batteries | |
| CN109560265B (en) | Coating method for effectively inhibiting oxygen loss of lithium-rich manganese-based positive electrode material | |
| WO2022100507A1 (en) | Positive electrode active material and electrochemical device | |
| CN107834050A (en) | A kind of lithium-enriched cathodic material of lithium ion battery and its improved method | |
| CN109713260A (en) | A kind of method of modifying of Phosphate coating lithium-rich manganese-based anode material | |
| Jin et al. | Improved electrochemical performances of li-and Mn-Rich layered oxides 0.4 Li4/3Mn2/3O2· 0.6 LiNi1/3Co1/3Mn1/3O2 cathode material by Co3O4 coating | |
| CN114420920B (en) | Fluorine ion gradient doped lithium-rich manganese-based positive electrode material, and preparation method and application thereof | |
| CN113788500A (en) | Surface modification method of lithium-rich manganese-based positive electrode material and lithium-rich manganese-based positive electrode material | |
| CN113880147A (en) | Preparation method for reducing voltage drop of positive electrode material, positive electrode material and application | |
| Meng et al. | Magnesium-doped Li [Li 0.2 Mn 0.54 Ni 0.13 Co 0.13] O 2 cathode with high rate capability and improved cyclic stability | |
| Tang et al. | La doping and coating enabled by one-step method for high performance Li1. 2Mn0. 54Ni0. 13Co0. 13O2 Li-rich cathode | |
| CN111799465B (en) | Composite coating method for manganese-based lithium battery electrode material | |
| CN110931733B (en) | Surface manganese doping and Li-Mn-PO4Coated high-nickel positive electrode material and preparation method and application thereof | |
| CN114649526B (en) | Inner-high-outer low-gradient doped lithium-rich manganese-based layered material and preparation method thereof | |
| CN114203993B (en) | Li (lithium ion battery) 2 SeO 4 Fast ion conductor modified lithium ion battery anode material | |
| CN114864894A (en) | High-pressure-resistant coating-layer-modified lithium-rich manganese-based positive electrode material and preparation method and application thereof | |
| CN114566625B (en) | Lithium-rich manganese-based positive electrode material with low pressure drop performance and preparation method and application thereof | |
| CN114864911A (en) | Modified high-nickel ternary cathode material and preparation method and application thereof | |
| CN114566647A (en) | Calcium phosphate coated high-nickel ternary cathode material and preparation method and application thereof | |
| CN114975914A (en) | High-nickel NCM ternary positive electrode material with surface coated with multiple substances and application thereof | |
| CN112607790A (en) | Preparation method of lithium-ion conductor-coated lithium-rich manganese-based positive electrode material | |
| CN112436135A (en) | Positive electrode material 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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |