CN113072049A - Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material - Google Patents
Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material Download PDFInfo
- Publication number
- CN113072049A CN113072049A CN202110325292.6A CN202110325292A CN113072049A CN 113072049 A CN113072049 A CN 113072049A CN 202110325292 A CN202110325292 A CN 202110325292A CN 113072049 A CN113072049 A CN 113072049A
- Authority
- CN
- China
- Prior art keywords
- manganese
- phosphate
- compaction
- steps
- carbon composite
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/45—Phosphates containing plural metal, or metal and ammonium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
-
- 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
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/624—Electric conductive fillers
- H01M4/625—Carbon or graphite
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
- C01P2004/32—Spheres
-
- 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
- C01P2006/11—Powder tap density
-
- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/028—Positive electrodes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses a preparation method of a high-compaction-density lithium manganese iron phosphate/carbon composite anode material, which has a chemical general formula as follows: LiMnxFeyPO4X is more than or equal to 0.5 and less than or equal to 0.9, and x + y is 1; the preparation method comprises the following steps: diluting phosphoric acid for later use, adding a manganese source, an iron source, a dispersing agent and deionized water into a sealable container, and introducing protective gas; adding diluted phosphoric acid into a sealed container, aging to ensure that the pH value is 2.0-5.0, and uniformly nucleating; will formCleaning the precipitate, drying in vacuum, and sintering at high temperature for the first time to form spherical particles A; preparing a solution by using lithium hydroxide monohydrate, adding the spherical particles A into the solution, carrying out spray drying, and sintering at a high temperature for the second time to obtain spherical particles B; and preparing a glucose solution, adding the spherical particles B into the glucose solution, spray-drying, and sintering at a high temperature for the third time to obtain the nano spherical lithium manganese iron phosphate/carbon composite material. The invention greatly improves the electrochemical performance and the material compaction density of the material.
Description
Technical Field
The invention belongs to the technical field of energy storage materials, and particularly relates to a preparation method of a high-compaction-density lithium manganese iron phosphate/carbon composite anode material.
Background
The use of Lithium Ion Batteries (LIBs) in hybrid and electric vehicles has generated considerable academic and industrial research interest. Polyanionic phosphate materials of olivine structure (LiMPO) since the original work of the Goodenough group 19974M ═ Fe, Mn, Co, and Ni) is widely studied as a positive electrode material because of its high theoretical capacity, thermal stability, and environmental friendliness. Based on safety requirements, LiFePO4(LFP) has been successfully used in LIBs as a replacement for LiMnPO4(LMP) provides the same theoretical specific capacity (170mAh g)-1) And with Fe2+/Fe3+In contrast, Mn2+/Mn3+Is higher, thus making the theoretical energy density of LMP about 20% higher than that of LFP. Despite these advantages of LMP, it is still difficult to obtain LMP with significantly improved power density, high specific capacity and long-term cycling stability. Extremely low lithium ion diffusion coefficient (D)Li，10-16～10-14cm2S) and electron conductivity: (<10-10s cm-1) Also reducing its electrochemical activity. In addition, LMP has a larger volume change during charge and discharge, and an unstable crystal structure during charge and discharge cycles results in a lower capacity retention rate. The Jahn-Teller effect, the dissolution of divalent Mn, leads to poor electrochemical performance of LMP. The ex-situ carbon coating method can only improve the conductivity between the secondary particles, and the in-situ carbon coating layer can be mixed with LiMnPO4The anode material primary particles form a three-dimensional continuous conductive system, and the electronic conductivity among the primary particles is improved. In micron-scale battery materials, the kinetics of charge storage are generally determined by Li in the microparticles+The diffusion rate of (c). Therefore, the reaction kinetics can be improved by nanocrystallizing the LMP material. The Fe doping can mitigate lattice distortion caused by the Jahn-Teller effect, thereby stabilizing the crystal structure and enhancing charge transfer. Therefore, replacing Mn with an appropriate amount of Fe is to increase LiMnPO4A method for synthesizing lithium manganese iron phosphate (LiMn) with excellent electrochemical performancexFe1-xPO4) Positive electrode materialIs very necessary.
In addition, the synthesis method and preparation process determine the LiMnxFe1-xPO4The intrinsic structural characteristics of the particle size, the particle size distribution, the morphology, the specific surface area, the crystallinity, the lattice defects and the like directly influence the lithium ion deintercalation process, namely determine the electrochemical properties of the material, such as charge-discharge capacity, cycle life and the like. The traditional synthesis method, namely the solid phase method, has the advantages of simple synthesis process, uniform particles of materials and large inter-particle space. The hydrothermal method has obvious advantages in controlling chemical composition and crystallite size, but the synthetic material is lamellar and cannot realize densification.
For example, chinese patent publication No. CN104009234A discloses a method for synthesizing LiMn, a positive electrode material for lithium ion batteries, by using a coprecipitation-microwave method0.7Fe0.3PO4By reacting Li with a catalyst of2CO3、Fe2O3After phosphoric acid is metered according to a certain molar ratio, preparing phosphoric acid into a phosphoric acid solution, and adding citric acid into the phosphoric acid solution to prepare an aqueous solution of citric acid and phosphoric acid; mixing Li2CO3、Fe2O3Adding, and stirring to obtain paste mixture; aging and microwave heat treatment to obtain a precursor A; in the same way with Li2CO3、MnCO3Or MnO2Mixing the precursors A and B, and adding a glucose solution to obtain a paste precursor; finally, the anode material is obtained through microwave sintering, and the discharge capacity of the prepared lithium iron manganese phosphate anode material is 138.6mAh g-1。
Chinese patent publication No. CN103515599A discloses a method for preparing a lithium manganese phosphate and carbon nanotube nanocomposite, which comprises dropping phosphoric acid into a lithium hydroxide solution to obtain lithium phosphate; adding manganese salt and ferric salt into the lithium phosphate dispersion liquid, stirring to obtain a precursor solution, then sintering at high temperature to obtain lithium manganese phosphate or iron-doped lithium manganese phosphate, then performing catalyst deposition on the surface of the lithium manganese phosphate or iron-doped lithium manganese phosphate, and finally sintering in the atmosphere of carbon source gas and protective gas to obtain the lithium manganese phosphate and carbon nano tube nanocomposite or iron-doped lithium manganese phosphate and carbon nano tube nanocomposite.
Chinese patent publication No. CN109524644A discloses LiMn1-xMgxPO4The preparation method of the/C positive electrode material comprises the following steps: (1) slowly dropping phosphoric acid or phosphate solution B into lithium salt solution A under the inert gas atmosphere and continuously stirring to obtain suspension C; (2) slowly pouring the manganese salt and magnesium salt mixed solution D into the suspension C, uniformly stirring and dispersing, performing microwave reaction, cooling, centrifuging, washing, vacuum drying and grinding to obtain manganese magnesium lithium phosphate precursor powder; (3) ball-milling and uniformly mixing the manganese-magnesium-lithium phosphate precursor powder and a carbon source, roasting in an inert gas atmosphere, and then grinding to obtain LiMn1-xMgxPO4the/C positive electrode material is characterized in that x is 0.01-0.15.
Chinese patent publication No. CN103413940A discloses a method for synthesizing nano-lithium manganese phosphate as a lithium ion battery anode material, which comprises the steps of dissolving phosphoric acid in deionized water to obtain a phosphoric acid solution, adding PEG400 in a stirring state to obtain a PEG400 phosphoric acid mixed solution, dissolving lithium hydroxide in deionized water to obtain a lithium hydroxide aqueous solution, adding the lithium hydroxide aqueous solution into the PEG400 phosphoric acid mixed solution under stirring to obtain a white emulsion, dissolving manganese sulfate in deionized water to prepare a manganese sulfate solution, adding the manganese sulfate solution into the obtained white emulsion under stirring to obtain a precursor emulsion, placing the precursor emulsion into a microwave reactor, controlling the temperature to be 140-180 ℃ to perform microwave reaction for 5-20 min, centrifuging, washing and drying to obtain the nano-lithium manganese phosphate as the lithium ion battery anode material.
Chinese patent publication No. CN102956887A discloses a preparation method of a nano-scale lithium manganese phosphate anode material, which comprises the following steps of mixing a lithium source, a manganese source, a phosphorus source and a doped element compound according to a molar ratio of (0.9-1): (0.9-1): (0.9-1): (0-0.1) preparing a solution, adding a complexing agent, and adding a carbon source into the solution to obtain a uniform colloid; drying the colloid to obtain precursor powder, heating the precursor powder in a protective atmosphere to obtain nano powder, and sintering the nano powder in the protective atmosphere to obtain the nano lithium manganese phosphate anode material.
The above-mentioned patent publications synthesize lithium manganese phosphate or iron-doped lithium manganese phosphate materials in different ways, but do not improve the compacted density of the materials.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a preparation method of a high-compaction-density lithium manganese iron phosphate/carbon composite anode material, the method prepares nano spherical particles by a three-step sintering synthesis method, the electrochemical properties such as discharge capacity and the like can be greatly improved, the product particles are regular in shape, reasonable in size distribution and smaller in particle gap, and the compaction density is greatly improved (reaching 2.8g cm)-3Above).
The invention is realized in such a way that a preparation method of the high-compaction-density lithium manganese iron phosphate/carbon composite anode material has a chemical general formula as follows: LiMnxFeyPO4The formula is/C, wherein x is more than or equal to 0.5 and less than or equal to 0.9, and x + y is 1;
the preparation method comprises the following steps:
1) diluting phosphoric acid to a mass concentration of 2-55% for later use, adding a manganese source, an iron source, a dispersing agent and deionized water into a sealable container, and introducing protective gas into the container;
2) slowly adding the diluted phosphoric acid solution into a sealed container to generate ferromanganese phosphate precipitate, aging for 10-20 days, and adjusting the pH value to be stable at 2.0-5.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated;
3) washing the formed precipitate for 3-5 times by using deionized water with the mass being 5-50 times that of the precipitate, then drying the precipitate at the temperature of 60-80 ℃ in vacuum, and then sintering the precipitate for the first time at a high temperature in a protective gas atmosphere to form spherical particles A with the particle size of 1-10 mu m;
4) taking monohydrate lithium hydroxide LiOH.H2O is prepared into a solution with the mass concentration of 1-15%, the spherical particles A are added into the solution, and after spray drying, the spherical particles B are obtained by secondary sintering at high temperature in a protective gas atmosphere;
5) preparing glucose into a solution with the mass concentration of 30-70%, adding the spherical particles B into the solution, spray-drying, and sintering at high temperature for the third time in a protective gas atmosphere to obtain the nano spherical lithium manganese iron phosphate/carbon (LiMn)xFeyPO4and/C) material.
In the above technical solution, preferably, the manganese source is manganese sulfate (MnSO)4) Manganese chloride (MnCl)2) Manganese oxalate (MnC)2O4) And manganese acetate (Mn (CH)3COO)2) One or more of them.
In the above technical solution, preferably, the iron source is ferrous sulfate (FeSO)4) Ferrous chloride (FeCl)2) Iron oxalate (FeC)2O4) And ferrous acetate (Fe (CH)3COO)2) One or more of them.
In the above technical scheme, preferably, the dispersant is one or more of polyethylene glycol 400, polyethylene wax, stearamide and stearic acid monoglyceride.
In the technical scheme, preferably, the mass ratio of the dispersing agent to the deionized water is (1-5): (70-150).
In the above technical solution, preferably, in the steps 1), 3), 4), and 5), the protective gas is argon or nitrogen.
In the above technical scheme, preferably, in the steps 4) and 5), a spray dryer or a centrifugal spray dryer or a pressure spray dryer is adopted to spray-dry the precursor material, wherein the inlet temperature of the spray dryer is 200-350 ℃, and the outlet temperature of the spray dryer is 60-120 ℃.
In the above technical scheme, preferably, in the steps 3), 4) and 5), the sintering temperature is 700-800 ℃ and the time is 4-12 hours.
The invention has the advantages and positive effects that:
(1) the method adopts a coprecipitation method to synthesize the ferromanganese source precursor, reaction conditions are easy to control in the reaction process, and the product has good performance repeatability.
(2) The prepared lithium iron manganese phosphate/carbon composite positive electrode material is nano-particles, is uniform in size distribution, and can effectively reduce the separation and embedding paths in the lithium ion charging and discharging process; the anode material has the advantages of high specific capacity, high working voltage, good rate capability, good cycling stability and the like.
(3) The lithium iron manganese phosphate/carbon composite anode material prepared by coprecipitation-three-step sintering synthesis can control the shape and size of particles in each step, and can improve the material compaction density which reaches 2.8g cm-3The above.
(4) The main raw materials used in the invention have rich sources and low price, and the invention has good application prospect.
Drawings
Fig. 1 is an SEM image of a high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material prepared in example 1 of the present invention;
fig. 2 is an XRD chart of the high-compacted-density lithium iron manganese phosphate/carbon composite positive electrode material prepared in example 1 of the present invention;
fig. 3 is a charge-discharge performance curve diagram of the high-compaction-density lithium iron manganese phosphate/carbon composite positive electrode material prepared in embodiment 1 of the invention at a magnification of 0.2C within a range of 2.5-4.5V.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following 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.
The embodiment of the invention provides a preparation method of a high-compaction-density lithium manganese iron phosphate/carbon composite anode material, which has a chemical general formula as follows: LiMnxFeyPO4The formula is/C, wherein x is more than or equal to 0.5 and less than or equal to 0.9, and x + y is 1;
the preparation method comprises the following steps:
1) diluting phosphoric acid to a mass concentration of 2-55% for later use, adding a manganese source, an iron source, a dispersing agent and deionized water into a sealable container, and introducing protective gas into the container;
2) slowly adding the diluted phosphoric acid solution into a sealed container to generate ferromanganese phosphate precipitate, aging for 10-20 days, and adjusting the pH value to be stable at 2.0-5.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated;
3) washing the formed precipitate for 3-5 times by using deionized water with the mass being 5-50 times that of the precipitate, then drying the precipitate at the temperature of 60-80 ℃ in vacuum, and then sintering the precipitate for the first time at a high temperature in a protective gas atmosphere to form spherical particles A with the particle size of 1-10 mu m;
4) taking monohydrate lithium hydroxide LiOH.H2O is prepared into a solution with the mass concentration of 1-15%, the spherical particles A are added into the solution, and after spray drying, the spherical particles B are obtained by secondary sintering at high temperature in a protective gas atmosphere;
5) preparing glucose into a solution with the mass concentration of 30-70%, adding the spherical particles B into the solution, spray-drying, and sintering at high temperature for the third time in a protective gas atmosphere to obtain the nano spherical lithium manganese iron phosphate/carbon (LiMn)xFeyPO4and/C) material.
The manganese source is manganese sulfate (MnSO)4) Manganese chloride (MnCl)2) Manganese oxalate (MnC)2O4) And manganese acetate (Mn (CH)3COO)2) One or more of them.
The iron source is ferrous sulfate (FeSO)4) Ferrous chloride (FeCl)2) Iron oxalate (FeC)2O4) And ferrous acetate (Fe (CH)3COO)2) One or more of them.
The dispersing agent is one or more of polyethylene glycol 400, polyethylene wax, stearamide and stearic acid monoglyceride.
The mass ratio of the dispersing agent to the deionized water is (1-5): (70-150).
In the steps 1), 3), 4) and 5), the protective gas is argon or nitrogen.
And in the steps 4) and 5), spray drying is carried out on the precursor material by adopting a spray dryer or a centrifugal spray dryer or a pressure spray dryer, wherein the inlet temperature of the spray drying is 200-350 ℃, and the outlet temperature of the spray drying is 60-120 ℃.
In the steps 3), 4) and 5), the sintering temperature is 700-800 ℃ and the time is 4-12 h.
Example 1
1) 28.7ml of 85% strength phosphoric acid are weighed out and slowly added to 200ml of deionized waterPrepared into solution for standby, and 45.30g of manganese sulfate MnSO is added into a sealed container455.61g of ferrous sulfate heptahydrate FeSO4·7H2O, 4g of polyethylene glycol 400 and 100ml of deionized water, and introducing a nitrogen protective gas into the container.
2) Slowly adding diluted phosphoric acid into a sealed container to generate ferromanganese phosphate precipitate, aging for 15 days, and adjusting the pH value to 4.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated.
3) The precipitate formed was washed 4 times with 10ml of deionized water and then dried under vacuum at 60 ℃. And then, sintering for the first time at the high temperature of 750 ℃ for 5 hours in the atmosphere of nitrogen protection gas to form spherical particles A with the particle size of 1-10 mu m.
4) 20.98g of lithium hydroxide monohydrate LiOH H were taken2And O, preparing a solution with the mass concentration of 10%, adding the spherical particles A into the solution, spray-drying at the inlet temperature of 200-350 ℃ and the outlet temperature of 60-120 ℃, and then sintering for 5 hours at the high temperature of 750 ℃ in a nitrogen atmosphere to obtain the spherical particles B.
5) Preparing 17.09g of glucose into a 50% mass concentration solution, adding the spherical particles B into the solution, spray-drying at an inlet temperature of 200-350 ℃ and an outlet temperature of 60-120 ℃, and sintering at a high temperature of 750 ℃ for 5 hours in a nitrogen protective atmosphere to obtain the nano spherical lithium manganese iron phosphate/carbon (LiMn)0.6Fe0.4PO4/C) composite positive electrode material.
Example 2
1) 28.7ml of 85% phosphoric acid was weighed and slowly added to 200ml of deionized water to dilute the solution and prepare a solution for use, and 37.77g of MnCl manganese dichloride was added into a sealed container225.35g of FeCl24g of polyethylene glycol 400 and 100ml of deionized water, and a nitrogen blanket was passed through the vessel.
2) Slowly adding diluted phosphoric acid into a sealed container to generate ferromanganese phosphate precipitate, aging for 12 days, and adjusting the pH value to 4.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated.
3) The precipitate formed was washed 4 times with 15ml of deionized water and then dried at 70 ℃ under vacuum. And then, sintering for the first time at the high temperature of 720 ℃ for 8 hours in the atmosphere of nitrogen protection gas to form spherical particles A with the particle size of 1-10 mu m.
4) 20.98g of lithium hydroxide monohydrate LiOH H were taken2And O, preparing a solution with the mass concentration of 10%, adding the spherical particles A into the solution, spray-drying at the inlet temperature of 200-350 ℃ and the outlet temperature of 60-120 ℃, and then sintering for 8 hours at the high temperature of 720 ℃ in a nitrogen atmosphere to obtain the spherical particles B.
5) Preparing 13.31g of glucose into a 50% mass concentration solution, adding the spherical particles B into the solution, spray-drying at the inlet temperature of 200-350 ℃ and the outlet temperature of 60-120 ℃, and then sintering for 8 hours at the high temperature of 720 ℃ in a nitrogen protective atmosphere for the third time to obtain the nano spherical lithium manganese iron phosphate/carbon (LiMn)0.6Fe0.4PO4/C) composite positive electrode material.
Example 3
1) 28.7ml of 85% phosphoric acid is weighed and slowly added into 200ml of deionized water to be diluted to prepare a solution for standby, and 42.89g of manganese oxalate MnSO is added into a sealed container428.77g of ferrous oxalate FeSO4·7H2O, 4g of polyethylene glycol 400 and 100ml of deionized water, and introducing a nitrogen protective gas into the container.
2) Slowly adding diluted phosphoric acid into a sealed container to generate ferromanganese phosphate precipitate, aging for 18 days, and adjusting the pH value to 4.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated.
3) The precipitate formed was washed 5 times with 20ml of deionized water and then dried under vacuum at 80 ℃. And then, sintering for the first time at the high temperature of 780 ℃ for 4 hours in the atmosphere of nitrogen protection gas to form spherical particles A with the particle size of 1-10 mu m.
4) 20.98g of lithium hydroxide monohydrate LiOH H were taken2And O, preparing a solution with the mass concentration of 10%, adding the spherical particles A into the solution, spray-drying at the inlet temperature of 200-350 ℃ and the outlet temperature of 60-120 ℃, and then sintering for 4 hours at the high temperature of 780 ℃ in a nitrogen atmosphere to obtain the spherical particles B.
5) Preparing 14.16g glucose into 50% solution, adding spherical granule B, and sprayingDrying, wherein the inlet temperature of spray drying is 200-350 ℃, the outlet temperature of spray drying is 60-120 ℃, and then, sintering for 4 hours at high temperature of 780 ℃ in the atmosphere of nitrogen protection gas for the third time to obtain the nano spherical lithium iron manganese phosphate/carbon (LiMn)0.6Fe0.4PO4/C) composite positive electrode material.
Performance testing
The nano-spherical lithium manganese iron phosphate/carbon (LiMn) prepared in example 1 was added0.6Fe0.4PO4and/C) testing the composite positive electrode material. FIG. 1 shows the nano-sized spherical lithium iron manganese phosphate/carbon (LiMn) prepared in example 10.6Fe0.4PO4and/C) a scanning electron microscope image of the composite cathode material, wherein as can be seen from FIG. 1, the secondary particles are spherical and are distributed in different particle sizes, and the particle size range is 2-15 mu m. The secondary particle balls are formed by stacking primary particles, and the primary particles are tightly connected and almost have no gaps.
FIG. 2 shows the nano-sized spherical lithium iron manganese phosphate/carbon (LiMn) prepared in example 10.6Fe0.4PO4The XRD pattern of the/C) composite anode material can be seen from figure 2, and the peak position of the pattern is matched with the standard PDF card of lithium iron manganese phosphate.
FIG. 3 shows the nano-sized spherical lithium iron manganese phosphate/carbon (LiMn) prepared in example 10.6Fe0.4PO4the/C) composite positive electrode material has a charge-discharge performance curve diagram under the multiplying power of 0.2C within the range of 2.5-4.5V, and as can be seen from figure 3, the specific discharge capacity reaches 154 mAh/g. With Li+Compared with Li, the material has two pairs of typical charge-discharge voltage platforms at about 4.1V and 3.5V, which respectively correspond to Mn3+/Mn2+And Fe3+/Fe2+Oxidation-reduction reaction of (1).
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or some or all of the technical features may be equivalently replaced, and the modifications or the replacements may not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (8)
1. A preparation method of a high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material is characterized by comprising the following steps of: the chemical general formula of the lithium iron manganese phosphate/carbon composite anode material is as follows: LiMnxFeyPO4The formula is/C, wherein x is more than or equal to 0.5 and less than or equal to 0.9, and x + y is 1;
the preparation method comprises the following steps:
1) diluting phosphoric acid to a mass concentration of 2-55% for later use, adding a manganese source, an iron source, a dispersing agent and deionized water into a sealable container, and introducing protective gas into the container;
2) slowly adding the diluted phosphoric acid solution into a sealed container to generate ferromanganese phosphate precipitate, aging for 10-20 days, and adjusting the pH value to be stable at 2.0-5.0 at any time to ensure that the ferromanganese phosphate precipitate is uniformly nucleated;
3) washing the formed precipitate for 3-5 times by using deionized water with the mass being 5-50 times that of the precipitate, then drying the precipitate at the temperature of 60-80 ℃ in vacuum, and then sintering the precipitate for the first time at a high temperature in a protective gas atmosphere to form spherical particles A with the particle size of 1-10 mu m;
4) taking monohydrate lithium hydroxide LiOH.H2O is prepared into a solution with the mass concentration of 1-15%, the spherical particles A are added into the solution, and after spray drying, the spherical particles B are obtained by secondary sintering at high temperature in a protective gas atmosphere;
5) preparing glucose into a solution with the mass concentration of 30-70%, adding the spherical particles B into the solution, spray-drying, and sintering at high temperature for the third time in a protective gas atmosphere to obtain the nano spherical lithium manganese iron phosphate/carbon (LiMn)xFeyPO4/C) composite positive electrode material.
2. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: the manganese source is manganese sulfate (MnSO)4) Manganese chloride (MnCl)2) Manganese oxalate (MnC)2O4) And manganese acetate (Mn (CH)3COO)2) One or more of them.
3. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: the iron source is ferrous sulfate (FeSO)4) Ferrous chloride (FeCl)2) Iron oxalate (FeC)2O4) And ferrous acetate (Fe (CH)3COO)2) One or more of them.
4. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: the dispersing agent is one or more of polyethylene glycol 400, polyethylene wax, stearamide and stearic acid monoglyceride.
5. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: the mass ratio of the dispersing agent to the deionized water is (1-5): (70-150).
6. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: in the steps 1), 3), 4) and 5), the protective gas is argon or nitrogen.
7. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: and in the steps 4) and 5), spray drying is carried out on the precursor material by adopting a spray dryer or a centrifugal spray dryer or a pressure spray dryer, wherein the inlet temperature of the spray drying is 200-350 ℃, and the outlet temperature of the spray drying is 60-120 ℃.
8. The method for preparing the high-compaction-density lithium iron manganese phosphate/carbon composite cathode material according to claim 1, wherein the method comprises the following steps: in the steps 3), 4) and 5), the sintering temperature is 700-800 ℃ and the time is 4-12 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110325292.6A CN113072049B (en) | 2021-03-26 | 2021-03-26 | Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110325292.6A CN113072049B (en) | 2021-03-26 | 2021-03-26 | Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113072049A true CN113072049A (en) | 2021-07-06 |
| CN113072049B CN113072049B (en) | 2023-01-31 |
Family
ID=76610445
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110325292.6A Active CN113072049B (en) | 2021-03-26 | 2021-03-26 | Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113072049B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114649530A (en) * | 2022-03-28 | 2022-06-21 | 湖北云翔聚能新能源科技有限公司 | Preparation method of nanometer lithium manganese iron phosphate material of vanadium-titanium doped composite carbon nanotube and nanometer lithium manganese iron phosphate material |
| CN114644328A (en) * | 2022-04-01 | 2022-06-21 | 星恒电源股份有限公司 | Preparation method of lithium iron manganese phosphate, positive electrode material and lithium ion battery |
| CN115159491A (en) * | 2022-08-05 | 2022-10-11 | 湖北融通高科先进材料有限公司 | Preparation method of high-safety high-capacity lithium iron manganese phosphate |
| CN115403023A (en) * | 2022-11-01 | 2022-11-29 | 浙江格派钴业新材料有限公司 | Method for preparing lithium iron manganese phosphate by supercritical hydrothermal method assisted spray drying |
| WO2023024651A1 (en) * | 2021-08-25 | 2023-03-02 | 北京当升材料科技股份有限公司 | Lithium iron manganese phosphate precursor, lithium iron manganese phosphate positive electrode material and preparation method therefor, electrode material, electrode, and lithium-ion battery |
| CN115947327A (en) * | 2023-02-07 | 2023-04-11 | 湖北亿纬动力有限公司 | Lithium manganese iron phosphate cathode material and preparation method and application thereof |
| CN116154156A (en) * | 2023-04-18 | 2023-05-23 | 江苏集萃分子工程研究院有限公司 | Spherical lithium iron manganese phosphate positive electrode material and preparation method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249208A (en) * | 2011-05-06 | 2011-11-23 | 朱鸥鹭 | Hydrothermal synthesis method for lithium ferromanganese phosphate anode material of lithium ion battery |
| CN103000898A (en) * | 2012-12-11 | 2013-03-27 | 中国电子科技集团公司第十八研究所 | Preparation method for carbon compounded lithium ferromanganese phosphate used for lithium ion battery |
| WO2014034775A1 (en) * | 2012-08-31 | 2014-03-06 | 戸田工業株式会社 | Method for producing carbon composite lithium manganese iron phosphate particle powder, carbon composite lithium manganese iron phosphate particle powder, and nonaqueous electrolyte secondary battery using carbon composite lithium manganese iron phosphate particle powder |
| CN105355880A (en) * | 2015-11-13 | 2016-02-24 | 山东精工电子科技有限公司 | Preparation method of LiFePO4/C modified ternary positive electrode material |
| CN107046128A (en) * | 2017-05-12 | 2017-08-15 | 龙能科技如皋市有限公司 | A kind of preparation method of iron manganese phosphate for lithium composite |
| CN109250698A (en) * | 2018-08-22 | 2019-01-22 | 江苏元景锂粉工业有限公司 | A kind of high-tap density lithium iron manganese phosphate anode material and its preparation method and application |
| CN111613786A (en) * | 2020-05-29 | 2020-09-01 | 东莞东阳光科研发有限公司 | Composite material and preparation method thereof |
-
2021
- 2021-03-26 CN CN202110325292.6A patent/CN113072049B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249208A (en) * | 2011-05-06 | 2011-11-23 | 朱鸥鹭 | Hydrothermal synthesis method for lithium ferromanganese phosphate anode material of lithium ion battery |
| WO2014034775A1 (en) * | 2012-08-31 | 2014-03-06 | 戸田工業株式会社 | Method for producing carbon composite lithium manganese iron phosphate particle powder, carbon composite lithium manganese iron phosphate particle powder, and nonaqueous electrolyte secondary battery using carbon composite lithium manganese iron phosphate particle powder |
| CN103000898A (en) * | 2012-12-11 | 2013-03-27 | 中国电子科技集团公司第十八研究所 | Preparation method for carbon compounded lithium ferromanganese phosphate used for lithium ion battery |
| CN105355880A (en) * | 2015-11-13 | 2016-02-24 | 山东精工电子科技有限公司 | Preparation method of LiFePO4/C modified ternary positive electrode material |
| CN107046128A (en) * | 2017-05-12 | 2017-08-15 | 龙能科技如皋市有限公司 | A kind of preparation method of iron manganese phosphate for lithium composite |
| CN109250698A (en) * | 2018-08-22 | 2019-01-22 | 江苏元景锂粉工业有限公司 | A kind of high-tap density lithium iron manganese phosphate anode material and its preparation method and application |
| CN111613786A (en) * | 2020-05-29 | 2020-09-01 | 东莞东阳光科研发有限公司 | Composite material and preparation method thereof |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023024651A1 (en) * | 2021-08-25 | 2023-03-02 | 北京当升材料科技股份有限公司 | Lithium iron manganese phosphate precursor, lithium iron manganese phosphate positive electrode material and preparation method therefor, electrode material, electrode, and lithium-ion battery |
| CN114649530A (en) * | 2022-03-28 | 2022-06-21 | 湖北云翔聚能新能源科技有限公司 | Preparation method of nanometer lithium manganese iron phosphate material of vanadium-titanium doped composite carbon nanotube and nanometer lithium manganese iron phosphate material |
| CN114644328A (en) * | 2022-04-01 | 2022-06-21 | 星恒电源股份有限公司 | Preparation method of lithium iron manganese phosphate, positive electrode material and lithium ion battery |
| CN114644328B (en) * | 2022-04-01 | 2023-10-20 | 星恒电源股份有限公司 | Preparation method of lithium iron manganese phosphate, positive electrode material and lithium ion battery |
| CN115159491A (en) * | 2022-08-05 | 2022-10-11 | 湖北融通高科先进材料有限公司 | Preparation method of high-safety high-capacity lithium iron manganese phosphate |
| CN115403023A (en) * | 2022-11-01 | 2022-11-29 | 浙江格派钴业新材料有限公司 | Method for preparing lithium iron manganese phosphate by supercritical hydrothermal method assisted spray drying |
| CN115947327A (en) * | 2023-02-07 | 2023-04-11 | 湖北亿纬动力有限公司 | Lithium manganese iron phosphate cathode material and preparation method and application thereof |
| CN116154156A (en) * | 2023-04-18 | 2023-05-23 | 江苏集萃分子工程研究院有限公司 | Spherical lithium iron manganese phosphate positive electrode material and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113072049B (en) | 2023-01-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113072049B (en) | Preparation method of high-compaction-density lithium manganese iron phosphate/carbon composite positive electrode material | |
| KR101403828B1 (en) | Li-Ni COMPLEX OXIDE PARTICLE POWDER FOR NONAQUEOUS ELECTROLYTE SECONDARY BATTERY, METHOD FOR PRODUCING THE SAME, AND NONAQUEOUS ELECTROLYTE SECONDARY BATTERY | |
| CN104882589B (en) | Carbon-coated ternary anode material and preparing method thereof, and lithium ion battery | |
| CN101789507B (en) | Electrode active material for anion-deficient lithium transition metal phosphate compound, method of preparing same, and electrochemical device using same | |
| CN101330141B (en) | Method for preparing lithium ionic battery anode material spherical LiFePO4 /C | |
| Zhao et al. | High performance LiMnPO 4/C prepared by a crystallite size control method | |
| CN104752718B (en) | A kind of LiMnxFe1‑xPO4Positive electrode active materials and preparation method thereof | |
| CN101826617B (en) | Preparation method of lithium iron phosphate | |
| CN112542589B (en) | Preparation method, product and application of positive electrode prelithiation material | |
| TW201335067A (en) | Electrode material, electrode board and lithium ion battery, and method of manufacturing electrode material and electrode board | |
| CN102110814B (en) | Preparation method of lithium iron phosphate and battery anode | |
| CN113066969A (en) | Preparation method of conductive polymer coated lithium manganese iron phosphate cathode material | |
| CN109360967A (en) | A kind of spherical LiFePO 4 cladding nickle cobalt lithium manganate battery material and preparation method | |
| CN103956485A (en) | Lithium iron phosphate electrode material having three-dimensional hierarchical structure, and preparation method thereof | |
| US20170092937A1 (en) | Electrode material for lithium-ion rechargeable battery, method for manufacturing electrode material for lithium-ion rechargeable battery, electrode for lithium-ion rechargeable battery, and lithium-ion rechargeable battery | |
| CN103208627A (en) | Ferric phosphate material and manufacturing method thereof | |
| CN107887583A (en) | A kind of doped lithium iron phosphate anode material and preparation method thereof | |
| CN103708434A (en) | Lithium iron phosphate material and preparation method thereof | |
| CN113651303A (en) | Preparation method of nano flaky iron phosphate and LiFePO prepared by using same4Positive electrode active material/C | |
| Zhou et al. | Fabrication of nanoplate Li-rich cathode material via surfactant-assisted hydrothermal method for lithium-ion batteries | |
| Du et al. | Synthesis of spinel LiMn2O4 with manganese carbonate prepared by micro-emulsion method | |
| JP4522682B2 (en) | Method for producing electrode material powder, electrode material powder and electrode, and lithium battery | |
| KR101170095B1 (en) | Method for synthesizing nanostructured gamma manganese oxide at atmospheric pressure and low temperature and spinel lithium manganese oxide thereof | |
| Kim et al. | Effects of the fluorine-substitution and acid treatment on the electrochemical performances of 0.3 Li2MnO3· 0.7 LiMn0. 60Ni0. 25Co0. 15O2 cathode material for Li-ion battery | |
| Yang et al. | Fast preparation of LiFePO4 nanoparticles for lithium batteries by microwave-assisted hydrothermal method |
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 |