CN111333107A - Preparation method of titanium-rich lithium titanate material - Google Patents

Preparation method of titanium-rich lithium titanate material Download PDF

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CN111333107A
CN111333107A CN202010263110.2A CN202010263110A CN111333107A CN 111333107 A CN111333107 A CN 111333107A CN 202010263110 A CN202010263110 A CN 202010263110A CN 111333107 A CN111333107 A CN 111333107A
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titanate
lithium hydroxide
lithium
titanium
temperature
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黄俊杰
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University of Shaoxing
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University of Shaoxing
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/003—Titanates
    • C01G23/005—Alkali titanates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G23/00—Compounds of titanium
    • C01G23/04—Oxides; Hydroxides
    • C01G23/047—Titanium dioxide
    • C01G23/053—Producing by wet processes, e.g. hydrolysing titanium salts
    • 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
    • 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
    • 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

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)

Abstract

The invention belongs to the field of lithium batteries, relates to the field of lithium titanate, and particularly relates to a preparation method of a titanium-rich lithium titanate material, which comprises the following steps: step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form stable n-butyl titanate ether liquid; step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 1-2h to obtain coated lithium hydroxide particles; and 3, putting the coated lithium hydroxide particles into a reaction kettle, reacting for 1-3h at constant temperature and constant pressure, then purging for 20-30min by adopting humid air, standing for reacting for 1-3h to obtain a titanate film-lithium hydroxide particles, and sintering to obtain the titanium-rich lithium titanate material. The invention solves the problem of poor conductivity of lithium titanate, greatly improves the electron transfer capacity by utilizing the conductivity of titanium dioxide, and effectively improves the performance of lithium titanate.

Description

Preparation method of titanium-rich lithium titanate material
Technical Field
The invention belongs to the field of lithium batteries, relates to the field of lithium titanate, and particularly relates to a preparation method of a titanium-rich lithium titanate material.
Background
Lithium titanate "zero strain materials" are being increasingly used in lithium ion batteries due to their superior cycle performance, good rate capability and reliable safety. The lithium titanate has a special three-dimensional lithium ion diffusion channel with a spinel structure, so that the lithium titanate has an obvious quick charge advantage and good high-low temperature performance; in addition, the safety is good, the service life is long, and the environment is protected, so that the electric vehicle has wide application space in the fields of electric motor coaches, energy storage, high-power equipment and the like. Especially in the field of energy storage, along with the continuous deepening of the power system reform in China and the rise of energy Internet, the increase of peak-load and frequency modulation requirements in the 'three north' area and the highlighting of the problems of wind abandonment and light abandonment, the application value of the energy storage in the fields of renewable energy consumption, distributed power generation, micro-grid and the like is more and more emphasized. Different from a power battery, the energy storage battery pays more attention to the performances of long service life, low cost and high safety of the battery, so that the advantages of the lithium titanate energy storage battery are very obvious. However, lithium titanate has a defect of poor conductivity.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a preparation method of a titanium-rich lithium titanate material, which solves the problem of poor conductivity of lithium titanate, greatly improves the electron transfer capacity by utilizing the conductivity of titanium dioxide, and effectively improves the performance of lithium titanate.
In order to achieve the technical purpose, the technical scheme of the invention is as follows:
a preparation method of a titanium-rich lithium titanate material comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form a stable n-butyl titanate ether solution, wherein the concentration of the n-butyl titanate in the anhydrous ether is 20-100 g/L;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 1-2h to obtain coated lithium hydroxide particles; the lithium hydroxide adopts nano-scale lithium hydroxide particles, the addition amount of the lithium hydroxide is 70-80% of the molar amount of the n-butyl titanate, the stirring speed is 1000-2000r/min, the stirring speed of stirring evaporation is 1000-2000r/min, and the temperature is 50-60 ℃;
step 3, putting the coated lithium hydroxide particles into a reaction kettle, reacting for 1-3h at constant temperature and constant pressure, then purging for 20-30min by adopting humid air, standing for reacting for 1-3h to obtain titanate films-lithium hydroxide particles, and sintering to obtain a titanium-rich lithium titanate material; the pressure of the constant-temperature and constant-pressure reaction is 0.2-0.3MPa, the temperature is 40-50 ℃, the humidity of the humid air is 30-50%, the purging speed is 10-20mL/min, the standing temperature is 80-90 ℃, and the sintering temperature is 500-600 ℃.
From the above description, it can be seen that the present invention has the following advantages:
1. the invention solves the problem of poor conductivity of lithium titanate, greatly improves the electron transfer capacity by utilizing the conductivity of titanium dioxide, and effectively improves the performance of lithium titanate.
2. According to the invention, a wrapping system is adopted, so that the combination effect of lithium hydroxide and titanic acid is improved, and a shell-core structure with lithium titanate as an inner core and titanium dioxide as a surface layer is formed.
Detailed Description
The present invention is described in detail with reference to examples, but the present invention is not limited to the claims.
A preparation method of a titanium-rich lithium titanate material comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, uniformly stirring to form a stable n-butyl titanate ether solution, wherein the concentration of n-butyl titanate in the anhydrous ether is 20-100g/L, and the n-butyl titanate has good solubility in the anhydrous ether;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 1-2h to obtain coated lithium hydroxide particles; the lithium hydroxide adopts nano-scale lithium hydroxide particles, the addition amount of the lithium hydroxide is 70-80% of the molar amount of the n-butyl titanate, the stirring speed is 1000-2000r/min, the stirring speed of stirring evaporation is 1000-2000r/min, and the temperature is 50-60 ℃; uniformly dispersing lithium hydroxide in n-butyl titanate ethyl ether liquid to form a stable suspension system, continuously evaporating and recovering anhydrous ethyl ether in the stirring and evaporation process, continuously increasing the concentration of n-butyl titanate, uniformly adhering the n-butyl titanate to the surface of lithium hydroxide particles until the lithium hydroxide particles are completely dried to obtain lithium hydroxide particles, and uniformly adhering n-butyl titanate to the surface of the particles;
step 3, putting the coated lithium hydroxide particles into a reaction kettle, reacting for 1-3h at constant temperature and constant pressure, then purging for 20-30min by adopting humid air, standing for reacting for 1-3h to obtain titanate films-lithium hydroxide particles, and sintering to obtain a titanium-rich lithium titanate material; the pressure of the constant-temperature and constant-pressure reaction is 0.2-0.3MPa, the temperature is 40-50 ℃, the humidity of the humid air is 30-50%, the purging speed is 10-20mL/min, the standing temperature is 80-90 ℃, and the sintering temperature is 500-600 ℃; in the drying process of the coated lithium hydroxide particles, anhydrous ether on the surface is completely evaporated, the lithium hydroxide particles have a certain amount of anhydrous ether residue based on the viscosity of n-butyl titanate, under the conditions of constant temperature and constant pressure, the internal anhydrous ether is further volatilized to form a structure that a film on the surface of n-butyl titanate wraps lithium hydroxide, wet air is adopted for blowing, water vapor is added into the whole system by the wet air, the water vapor and the n-butyl titanate on the surface of the lithium hydroxide form hydrolysis reaction and is converted into surface titanic acid, lithium hydroxide particles with a surface film being a titanic acid liquid film are formed by standing reaction, in the sintering process, the lithium hydroxide and the titanic acid form reaction and are converted into lithium titanate, meanwhile, the titanic acid is converted into titanium dioxide based on the titanic acid being a liquid film structure and is uniformly dispersed on the surface of the lithium hydroxide particles, therefore, forming the titanium-rich lithium titanate material which takes lithium titanate as a nuclear layer and titanium dioxide as a shell layer.
Example 1
A preparation method of a titanium-rich lithium titanate material comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form a stable n-butyl titanate ether solution, wherein the concentration of the n-butyl titanate in the anhydrous ether is 20 g/L;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and then stirring and evaporating for 1h to obtain coated lithium hydroxide particles; the lithium hydroxide adopts nano-scale lithium hydroxide particles, the addition amount of the lithium hydroxide is 70 percent of the molar amount of the n-butyl titanate, the stirring speed is 1000r/min, the stirring speed of stirring evaporation is 1000r/min, and the temperature is 50 ℃;
step 3, putting the coated lithium hydroxide particles into a reaction kettle, reacting for 1h at constant temperature and constant pressure, then purging for 20min by adopting humid air, standing for reacting for 1h to obtain a titanate film-lithium hydroxide particles, and sintering to obtain a titanium-rich lithium titanate material; the pressure of the constant-temperature and constant-pressure reaction is 0.2MPa, the temperature is 40 ℃, the humidity of the humid air is 30%, the purging speed is 10mL/min, the standing temperature is 80 ℃, and the sintering temperature is 500 ℃.
By taking a commercially available lithium titanate material as a comparative example, under the same detection conditions, the conductivity of the titanium-rich lithium titanate material prepared in the example is improved by 5% compared with that of the comparative example, and after 200 times of repeated use, the conductivity loss of the lithium titanate in the example is only 2%, so that good stability is achieved.
Example 2
A preparation method of a titanium-rich lithium titanate material comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form a stable n-butyl titanate ether solution, wherein the concentration of the n-butyl titanate in the anhydrous ether is 100 g/L;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 2 hours to obtain coated lithium hydroxide particles; the lithium hydroxide adopts nano-scale lithium hydroxide particles, the addition amount of the lithium hydroxide is 80 percent of the molar amount of the n-butyl titanate, the stirring speed is 2000r/min, the stirring speed of stirring evaporation is 2000r/min, and the temperature is 60 ℃;
step 3, putting the coated lithium hydroxide particles into a reaction kettle for constant-temperature and constant-pressure reaction for 3 hours, then purging with humid air for 30min, standing for reaction for 3 hours to obtain titanate films-lithium hydroxide particles, and sintering to obtain a titanium-rich lithium titanate material; the pressure of the constant-temperature and constant-pressure reaction is 0.3MPa, the temperature is 50 ℃, the humidity of the humid air is 50%, the purging speed is 20mL/min, the standing temperature is 90 ℃, and the sintering temperature is 600 ℃.
By taking a commercially available lithium titanate material as a comparative example, under the same detection conditions, the conductivity of the titanium-rich lithium titanate material prepared in the example is improved by 7% compared with that of the comparative example, and after 200 times of repeated use, the conductivity loss of the lithium titanate in the example is only 3%, so that good stability is achieved.
Example 3
A preparation method of a titanium-rich lithium titanate material comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form a stable n-butyl titanate ether solution, wherein the concentration of the n-butyl titanate in the anhydrous ether is 60 g/L;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 2 hours to obtain coated lithium hydroxide particles; the lithium hydroxide adopts nano-scale lithium hydroxide particles, the addition amount of the lithium hydroxide is 75 mol of n-butyl titanate, the stirring speed is 1500r/min, the stirring speed of stirring evaporation is 1500r/min, and the temperature is 55 ℃;
step 3, putting the coated lithium hydroxide particles into a reaction kettle for constant-temperature and constant-pressure reaction for 2 hours, then purging with humid air for 25 minutes, standing for reaction for 1-3 hours to obtain a titanate film-lithium hydroxide particles, and sintering to obtain a titanium-rich lithium titanate material; the pressure of the constant-temperature and constant-pressure reaction is 0.3MPa, the temperature is 45 ℃, the humidity of the humid air is 40%, the purging speed is 15mL/min, the standing temperature is 85 ℃, and the sintering temperature is 550 ℃.
By taking a commercially available lithium titanate material as a comparative example, under the same detection conditions, the conductivity of the titanium-rich lithium titanate material prepared in the example is improved by 6% compared with that of the comparative example, and after 200 times of repeated use, the conductivity loss of the lithium titanate in the example is only 2%, so that good stability is achieved.
In summary, the invention has the following advantages:
1. the invention solves the problem of poor conductivity of lithium titanate, greatly improves the electron transfer capacity by utilizing the conductivity of titanium dioxide, and effectively improves the performance of lithium titanate.
2. According to the invention, a wrapping system is adopted, so that the combination effect of lithium hydroxide and titanic acid is improved, and a shell-core structure with lithium titanate as an inner core and titanium dioxide as a surface layer is formed.
It should be understood that the detailed description of the invention is merely illustrative of the invention and is not intended to limit the invention to the specific embodiments described. It will be appreciated by those skilled in the art that the present invention may be modified or substituted equally as well to achieve the same technical result; as long as the use requirements are met, the method is within the protection scope of the invention.

Claims (4)

1. A preparation method of a titanium-rich lithium titanate material is characterized by comprising the following steps: the method comprises the following steps:
step 1, adding n-butyl titanate into anhydrous ether, and uniformly stirring to form stable n-butyl titanate ether liquid;
step 2, adding lithium hydroxide into n-butyl titanate ethyl ether solution, uniformly stirring, and stirring and evaporating for 1-2h to obtain coated lithium hydroxide particles;
and 3, putting the coated lithium hydroxide particles into a reaction kettle, reacting for 1-3h at constant temperature and constant pressure, then purging for 20-30min by adopting humid air, standing for reacting for 1-3h to obtain a titanate film-lithium hydroxide particles, and sintering to obtain the titanium-rich lithium titanate material.
2. The method of preparing a titanium-rich lithium titanate material according to claim 1, characterized in that: the concentration of the n-butyl titanate in the step 1 in the anhydrous ether is 20-100 g/L.
3. The method of preparing a titanium-rich lithium titanate material according to claim 1, characterized in that: the lithium hydroxide in the step 2 adopts nano-scale lithium hydroxide particles, the adding amount of the lithium hydroxide is 70-80% of the molar amount of the n-butyl titanate, the stirring speed is 1000-2000r/min, the stirring speed for stirring and evaporating is 1000-2000r/min, and the temperature is 50-60 ℃.
4. The method of preparing a titanium-rich lithium titanate material according to claim 1, characterized in that: the pressure of the constant-temperature and constant-pressure reaction in the step 3 is 0.2-0.3MPa, the temperature is 40-50 ℃, the humidity of the humid air is 30-50%, the purging speed is 10-20mL/min, the standing temperature is 80-90 ℃, and the sintering temperature is 500-600 ℃.
CN202010263110.2A 2020-04-07 2020-04-07 Preparation method of titanium-rich lithium titanate material Withdrawn CN111333107A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114573917A (en) * 2022-03-14 2022-06-03 青岛颐世保塑料有限公司 Preparation method of special laminating color master batch for outdoor tarpaulin
CN114573917B (en) * 2022-03-14 2024-06-07 青岛颐世保塑料有限公司 Preparation method of special film-coating color master batch for outdoor tarpaulin

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114573917A (en) * 2022-03-14 2022-06-03 青岛颐世保塑料有限公司 Preparation method of special laminating color master batch for outdoor tarpaulin
CN114573917B (en) * 2022-03-14 2024-06-07 青岛颐世保塑料有限公司 Preparation method of special film-coating color master batch for outdoor tarpaulin

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Application publication date: 20200626