CN109065856B - Modification method of lithium titanate negative electrode material of lithium ion battery - Google Patents
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Abstract
The invention discloses a method for modifying a lithium titanate negative electrode material of a lithium ion battery, which comprises the steps of placing a pure titanium sheet in an acid solution, soaking and calcining the pure titanium sheet to obtain a titanium dioxide film, soaking the titanium dioxide film in a lithium source sol, pre-burning the titanium dioxide film by an extraction method to obtain a lithium titanate precursor film, preparing a ytterbium silicate coating layer on the surface of a substrate by using the lithium titanate precursor film as the substrate and adopting a plasma spraying-physical vapor deposition technology, and calcining the ytterbium silicate coating lithium titanate film negative electrode material to obtain the ytterbium silicate coated lithium titanate negative electrode material. The ytterbium silicate coated lithium titanate film negative electrode material obtained after modification can inhibit growth of lithium titanate particles, inhibit water absorption of the material, effectively keep stable structure of lithium titanate in repeated charge and discharge processes, and improve multiplying power, circulation and chemical stability of lithium titanate.
Description
Technical Field
The invention relates to the field of lithium ion battery manufacturing, in particular to a method for modifying a lithium titanate negative electrode material of a lithium ion battery.
Background
The traditional negative electrode material is mainly a carbon material which has the advantages of good cycling stability, low charge and discharge platform and the like, but has some defects, such as potential safety hazard of lithium dendrite precipitation, insufficient speed of energy release, unsuitability for equipment needing instantaneous strong current and the like. Lithium titanate (Li) in contrast to carbon material4Ti5O12) Has the obvious advantages that the theoretical specific capacity of the lithium titanate material is 175mAh/g, the actual specific capacity is more than 160mAh/g, the cycle life of the lithium titanate is long, and Li4Ti5O12The lithium ion battery cathode material is a zero-strain material, lithium ions have good mobility, and the zero-strain material attracts great attention in lithium battery cathode materials.
Li4Ti5O12The main synthesis methods include solid-phase reaction method, sol-gel, hydrothermal ionExchange method, etc. Lai and the like use a titanium source and a lithium source to be mixed by ball milling, and porous Li is prepared after calcination in a high-temperature furnace4Ti5O12The specific discharge capacity after 50 cycles of 10C multiplying power charge-discharge cycle is 143.4mAh/g (Ball impedance assisted lithium-state reaction of mesoporous Li)4Ti5O12for lithium-ion batteries, Journal of Power Sources,2013,226: 71-74). Zhang et al use a modified sol-gel method for Li preparation4Ti5O12Preparation of nano-grade Li by using EDTA and citric acid as chelating agent4Ti5O12High specific capacity, excellent rate capability and cycle performance (Li)4Ti5O12prepared by a modified circulating acid sol-gel method for lithium-ion batteries in Journal of Power Sources 2013,236: 118-. Zhang Huan et al react TiO2Mixing with NaOH solution, preparing titanic acid nano-tube through hydrothermal reaction, performing ion exchange reaction with LiOH solution, and performing heat treatment to obtain lithium titanate, wherein the lithium titanate shows excellent rate capability and has a specific discharge capacity of 140mAh/g under 10C rate (the & ltion exchange method is used for synthesizing nano-scale lithium ion battery cathode material Li)4Ti5O12The book of inorganic chemistry, 2010, 26(9): 1539).
However, the lithium titanate negative electrode material is easy to generate gas in the battery manufacturing process, so that the electrode/electrolyte interface impedance is increased, the cycle performance is rapidly attenuated, the rate performance is reduced, the battery life is shortened, and the application of lithium titanate is greatly influenced.
Disclosure of Invention
The invention aims to solve the technical problem of providing a method for modifying lithium titanate cathode material of lithium ion battery, so that ytterbium silicate (YB)2SiO5) The lithium titanate can be effectively coated on the surface of lithium titanate, the growth of particles is inhibited, higher electrochemical activity is shown, the pH value of the negative electrode material can be reduced, and the water absorption of the negative electrode material is inhibited.
The technical scheme of the invention is as follows:
a modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) soaking the pure titanium sheet in an acid solution at normal temperature and pressure for 10-30h, taking out, cleaning until the pH value is 6-8, and then drying and calcining to obtain a titanium dioxide film;
(2) adding a chelating agent into an absolute ethyl alcohol solution containing a lithium source, and stirring in a water bath at 60-80 ℃ to obtain sol;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling, and then sequentially drying and presintering to obtain a layer of lithium titanate precursor film;
(4) taking the lithium titanate precursor film obtained in the step (3) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix by adopting a plasma spraying-physical vapor deposition technology in a rotating manner at 40-60r/min, wherein the method comprises the following specific steps: fixing the layer of lithium titanate precursor film obtained in the step (3) on a tool, performing ultrasonic degreasing and cleaning, then placing the film on a spraying clamp, preheating the matrix to 600-800 ℃ through plasma, and finally spraying ytterbium silicate powder to obtain a lithium titanate precursor film coated by ytterbium silicate;
(5) and (5) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (4) to obtain the lithium titanate film negative electrode material coated with the ytterbium silicate.
Repeating the steps (1) to (3) to obtain a lithium titanate precursor film with a preset number of layers, and then taking the obtained lithium titanate precursor film with the preset number of layers as the matrix in the step (4).
In the step (1), before the pure titanium sheet is soaked in the acid solution, the pure titanium sheet is polished to be smooth by using abrasive paper, and then is cleaned by ultrasonic cleaning sequentially by using acetone, absolute ethyl alcohol and deionized water; the acidic solution is selected from HCL solution and HNO3Solutions or H2SO4The molar concentration of the acid solution is 6-10 mol/L; soaking the pure titanium sheet in an acid solution, then cleaning the pure titanium sheet with deionized water until the pH value is 6-8, drying the pure titanium sheet in a drying box at 80-100 ℃ for 1-10h, and then calcining the pure titanium sheet at 650 ℃ for 3-5h to obtain the titanium dioxide film.
In the step (2), the molar concentration of the lithium source in the absolute ethyl alcohol solution containing the lithium source is 0.1-3mol/L, and the lithium source is one or a mixture of several of lithium hydroxide, lithium acetate and lithium nitrate; the mass concentration of the chelating agent is 1-15%, and the chelating agent is one or a mixture of more of ethylenediamine tetraacetic acid, oxalic acid and citric acid.
In the step (2), the stirring time in water bath is 2-12 h.
In the step (3), the titanium dioxide film is immersed into the sol, slowly pulled after 20 seconds, put into a drying box to be dried for 1-10 hours at the temperature of 80-100 ℃, and then presintered for 3-5 hours at the temperature of 350-450 ℃ to obtain a layer of lithium titanate precursor film.
In the step (4), the lithium titanate precursor film is fixed on a tool, ultrasonic degreasing is sequentially carried out on the matrix by using kerosene, acetone and alcohol, and the matrix is placed on a spraying fixture after being cleaned by deionized water.
In the step (4), a double-pipe spray gun is adopted to spray the matrix, before spraying, the spraying vacuum tank is pumped to 150-.
In the step (4), the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 1-5%.
In the step (5), the lithium titanate precursor film coated with ytterbium silicate is placed in an air atmosphere and calcined at the temperature of 700-900 ℃ for 5-10h to obtain the lithium titanate film coated with ytterbium silicate.
The invention has the advantages that:
(1) the method comprises the steps of soaking pure titanium sheets in acid, calcining to form a titanium dioxide film, soaking the titanium dioxide film into lithium salt sol, pre-burning to remove water and carbon in a chelating agent, and preparing YB on the surface of a substrate by adopting a plasma spraying-physical vapor deposition technology2SiO5Coating layer of (2), calcining to obtain YB2SiO5A coated lithium titanate modified negative electrode material.
(2) YB in the invention2SiO5The lithium titanate powder can be effectively coated on the surface of lithium titanate, so that the growth of lithium titanate particles is inhibited, the water absorption of the material is inhibited, the stable structure of the lithium titanate can be effectively maintained in the repeated charging and discharging process, and the multiplying power, the circulation and the chemical stability of the lithium titanate are improved.
(3) YB prepared by the invention2SiO5The coated lithium titanate film negative electrode material reduces the acting force between the migrating ions and the main framework and reduces the charge transfer impedance, wherein the calcining process improves the reaction activity of lithium titanate, is beneficial to overcoming the kinetic limitation of the charging and discharging process, reduces the polarization phenomenon and improves the reversible capacity and the cycle performance.
Drawings
Fig. 1 is an X-ray diffraction pattern of an ytterbium silicate-coated lithium titanate thin film negative electrode material prepared in example 1 of the present invention.
Fig. 2 is a cycle performance diagram of the ytterbium silicate coated lithium titanate thin film negative electrode material prepared in example 1 of the present invention and the lithium titanate negative electrode material prepared in the comparative example at 0.2C, 1C, and 2C magnifications.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, then putting the pure titanium sheet into a HCL solution with the molar concentration of 6mol/L at normal temperature and normal pressure, soaking for 10 hours, taking out, then cleaning by using deionized water until the pH value is 6, finally putting the pure titanium sheet into a drying box, drying for 1 hour at 80 ℃, and calcining for 3 hours at 350 ℃ to obtain a titanium dioxide film;
(2) adding an ethylene diamine tetraacetic acid chelating agent into an anhydrous ethanol solution containing lithium hydroxide, and stirring for 2 hours in a water bath at 60 ℃ to obtain sol; wherein the molar concentration of the lithium hydroxide is 0.1mol/L, and the mass concentration of the ethylene diamine tetraacetic acid is 1%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying for 1 hour at 80 ℃ in a pouring drying oven, and presintering for 3 hours at 350 ℃ to obtain a layer of lithium titanate precursor film;
(4) taking the lithium titanate precursor film obtained in the step (3) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix by adopting a plasma spraying-physical vapor deposition technology in a rotating manner at 40r/min, wherein the method comprises the following specific steps: fixing the layer of lithium titanate precursor film obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the matrix on a spraying fixture, pumping a spraying vacuum tank to 120Pa before spraying, igniting a spray gun when argon is backfilled to 3000Pa, preheating the matrix to 600 ℃ through plasma, adjusting the spraying distance to 800mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time for 30s to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 1%;
(5) and (5) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (4) for 5 hours at 700 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
From FIG. 1, YB can be seen2SiO5The structure of the lithium titanate is not changed in the coating, and the crystallinity is good.
Referring to fig. 2, the ytterbium silicate-coated lithium titanate film negative electrode material prepared in this embodiment 1 has a specific discharge capacity of 164.89mAh/g at a rate of 0.2C, a specific discharge capacity of 161.46mAh/g at a rate of 2C, and a capacity retention rate of 98.97% after 50 cycles.
Example 2
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, then putting the pure titanium sheet into a HCL solution with the molar concentration of 8mol/L at normal temperature and normal pressure, soaking for 15 hours, then taking out, then cleaning by using deionized water until the pH value is 7, finally putting the pure titanium sheet into a drying box, drying for 5 hours at the temperature of 90 ℃, and calcining for 4 hours at the temperature of 450 ℃ to obtain a titanium dioxide film;
(2) adding an oxalic acid chelating agent into an absolute ethyl alcohol solution containing lithium acetate, and stirring for 6 hours in a water bath at 70 ℃ to obtain sol; wherein the molar concentration of lithium acetate is 1.5mol/L, and the mass concentration of oxalic acid is 5%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying for 4 hours at 90 ℃ in a pouring drying oven, and presintering for 4 hours at 400 ℃ to obtain a layer of lithium titanate precursor film;
(4) repeating the steps (1) to (3) to obtain a four-layer lithium titanate precursor film;
(5) taking the four-layer lithium titanate precursor film obtained in the step (4) as a matrix, and adopting a plasma spraying-physical vapor deposition technology to prepare a coating layer of ytterbium silicate on the surface of the matrix in a rotating manner at 50r/min, wherein the method comprises the following specific steps: fixing the four-layer lithium titanate precursor film obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the cleaned matrix on a spraying fixture, pumping a spraying vacuum tank to 135Pa before spraying, igniting a spray gun when backfilling argon to 3400Pa, preheating the matrix to 700 ℃ firstly by using plasma, adjusting the spraying distance to 900mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time for 2min to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 3%;
(6) and (4) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (5) for 7 hours at 700 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
The ytterbium silicate coated lithium titanate film negative electrode material prepared in the embodiment 2 has a specific discharge capacity of 165.26mAh/g at a rate of 0.2C, a specific discharge capacity of 162.13mAh/g at a rate of 2C, and a capacity retention rate of 99.52% after 50 cycles.
Example 3
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, then putting the pure titanium sheet into a HCL solution with the molar concentration of 10mol/L at normal temperature and normal pressure, soaking for 25 hours, taking out, then cleaning by using deionized water until the pH value is 7.5, finally putting the pure titanium sheet into a drying box, drying for 8 hours at 100 ℃, and calcining for 4 hours at 600 ℃ to obtain a titanium dioxide film;
(2) adding a citric acid chelating agent into an absolute ethyl alcohol solution containing lithium nitrate, and stirring in a water bath at the temperature of 80 ℃ for 12 hours to obtain sol; wherein the molar concentration of lithium nitrate is 3mol/L, and the mass concentration of citric acid is 15%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying for 6 hours at 85 ℃ in a pouring drying oven, and presintering for 4 hours at 400 ℃ to obtain a layer of lithium titanate precursor film;
(4) repeating the steps (1) to (3) to obtain a seven-layer lithium titanate precursor film;
(5) and (3) taking the seven-layer lithium titanate precursor film obtained in the step (4) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix by adopting a plasma spraying-physical vapor deposition technology in a rotating mode at 60r/min, wherein the specific steps are as follows: fixing the seven-layer lithium titanate precursor film obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the cleaned matrix on a spraying fixture, pumping a spraying vacuum tank to 150Pa before spraying, igniting a spray gun when backfilling argon to 4000Pa, preheating the matrix to 800 ℃ firstly by using plasma, adjusting the spraying distance to 1000mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time for 10min to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 5%;
(6) and (4) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (5) for 10 hours at 900 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
The ytterbium silicate coated lithium titanate film negative electrode material prepared in the embodiment 3 has a specific discharge capacity of 165.58mAh/g at a rate of 0.2C, a specific discharge capacity of 161.96mAh/g at a rate of 2C, and a capacity retention rate of 99.43% after 50 cycles.
Example 4
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, and then putting HNO with the molar concentration of 6mol/L at normal temperature and normal pressure3Soaking the solution for 10h, taking out, washing with deionized water until the pH value is 7, finally drying in a drying oven at 80 ℃ for 6h, and calcining at 450 ℃ for 4.5h to obtain a titanium dioxide film;
(2) adding an oxalic acid chelating agent into an anhydrous ethanol solution containing lithium hydroxide, and stirring for 6 hours in a water bath at the temperature of 75 ℃ to obtain sol; wherein the molar concentration of the lithium hydroxide is 2.5mol/L, and the mass concentration of the oxalic acid is 8 percent;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling the titanium dioxide film after 20 seconds, drying the titanium dioxide film in a pouring drying oven at 95 ℃ for 7 hours, and presintering the titanium dioxide film at 400 ℃ for 4.5 hours to obtain a layer of lithium titanate precursor film;
(4) repeating the steps (1) to (3) to obtain ten layers of lithium titanate precursor films;
(5) and (3) taking the ten layers of lithium titanate precursor films obtained in the step (4) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix in a rotating manner at 45r/min by adopting a plasma spraying-physical vapor deposition technology, wherein the method comprises the following specific steps: fixing the ten layers of lithium titanate precursor films obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the matrix on a spraying fixture, pumping a spraying vacuum tank to 130Pa before spraying, igniting a spray gun when backfilling argon to 3600Pa, preheating the matrix to 750 ℃ firstly by using plasma, adjusting the spraying distance to 880mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time to be 6min to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 3%;
(6) and (4) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (5) for 10 hours at 900 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
The ytterbium silicate coated lithium titanate film negative electrode material prepared in the embodiment 4 has a specific discharge capacity of 164.65mAh/g at a rate of 0.2C, a specific discharge capacity of 161.31mAh/g at a rate of 2C, and a capacity retention rate of 98.87% after 50 cycles.
Example 5
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, and then putting HNO with the molar concentration of 6mol/L at normal temperature and normal pressure3Soaking the solution for 25h, taking out, cleaning with deionized water until the pH value is 6.5, drying in a drying oven at 95 ℃ for 7h, and calcining at 600 ℃ for 3h to obtain a titanium dioxide film;
(2) adding a citric acid chelating agent into an absolute ethyl alcohol solution containing lithium hydroxide, and stirring for 8 hours in a water bath at the temperature of 75 ℃ to obtain sol; wherein the molar concentration of the lithium hydroxide is 2.5mol/L, and the mass concentration of the citric acid is 6%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying for 5 hours at 85 ℃ in a pouring drying oven, and presintering for 5 hours at 400 ℃ to obtain a layer of lithium titanate precursor film;
(4) repeating the steps (1) to (3) to obtain a four-layer lithium titanate precursor film;
(5) taking the four-layer lithium titanate precursor film obtained in the step (4) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix by adopting a plasma spraying-physical vapor deposition technology in a rotating mode at 45r/min, wherein the specific steps are as follows: fixing the four-layer lithium titanate precursor film obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the matrix on a spraying fixture, pumping a spraying vacuum tank to 135Pa before spraying, igniting a spray gun when backfilling argon to 3600Pa, preheating the matrix to 750 ℃ firstly by using plasma, adjusting the spraying distance to 950mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time for 2min to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 1.5%;
(6) and (4) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (5) for 6 hours at 750 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
The ytterbium silicate coated lithium titanate film negative electrode material prepared in the embodiment 5 has a specific discharge capacity of 165.74mAh/g at a rate of 0.2C, a specific discharge capacity of 161.92mAh/g at a rate of 2C, and a capacity retention rate of 99.35% after 50 cycles.
Example 6
A modification method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, then sequentially using acetone, absolute ethyl alcohol and deionized water to carry out ultrasonic cleaning, and then adding H with the molar concentration of 10mol/L at normal temperature and normal pressure2SO4Soaking the solution for 30h, taking out, cleaning with deionized water until the pH value is 8, finally drying in a drying oven at 100 ℃ for 10h, and calcining at 650 ℃ for 5h to obtain a titanium dioxide film;
(2) adding an ethylenediaminetetraacetic acid chelating agent into an absolute ethyl alcohol solution containing lithium nitrate, and stirring in a water bath at the temperature of 80 ℃ for 12 hours to obtain sol; wherein the molar concentration of lithium nitrate is 3mol/L, and the mass concentration of ethylene diamine tetraacetic acid is 15%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying in a pouring drying oven at 100 ℃ for 10 hours, and presintering at 450 ℃ for 5 hours to obtain a layer of lithium titanate precursor film;
(4) repeating the steps (1) to (3) to obtain ten layers of lithium titanate precursor films;
(5) and (3) taking the ten layers of lithium titanate precursor films obtained in the step (4) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix in a rotating manner at 45r/min by adopting a plasma spraying-physical vapor deposition technology, wherein the method comprises the following specific steps: fixing the ten layers of lithium titanate precursor films obtained in the step (4) on a tool, sequentially carrying out ultrasonic oil removal on a matrix by using kerosene, acetone and alcohol, cleaning deionized water, then placing the matrix on a spraying fixture, pumping a spraying vacuum tank to 150Pa before spraying, igniting a spray gun when backfilling argon to 4000Pa, preheating the matrix to 800 ℃ firstly by using plasma, adjusting the spraying distance to 1000mm, conveying ytterbium silicate powder into a double pipe for spraying, and controlling the spraying time to be 11min to obtain a ytterbium silicate coated lithium titanate precursor film; wherein the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 5%;
(6) and (4) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (5) for 10 hours at 900 ℃ in an air atmosphere to obtain the lithium titanate film cathode material coated with the ytterbium silicate.
The ytterbium silicate coated lithium titanate film negative electrode material prepared in the embodiment 6 has a specific discharge capacity of 165.28mAh/g at a rate of 0.2C, a specific discharge capacity of 161.38mAh/g at a rate of 2C, and a capacity retention rate of 99.02% after 50 cycles.
Comparative example
A preparation method of a lithium titanate negative electrode material of a lithium ion battery specifically comprises the following steps:
(1) polishing a pure titanium sheet by using sand paper, sequentially carrying out ultrasonic cleaning by using acetone, absolute ethyl alcohol and deionized water, then putting the pure titanium sheet into a HCL solution with the molar concentration of 6mol/L at normal temperature and normal pressure, soaking for 10 hours, taking out, then cleaning by using deionized water until the pH value is 6, finally putting the pure titanium sheet into a drying box, drying for 1 hour at 80 ℃, and calcining for 3 hours at 350 ℃ to obtain a titanium dioxide film;
(2) adding an ethylene diamine tetraacetic acid chelating agent into an anhydrous ethanol solution containing lithium hydroxide, and stirring for 2 hours in a water bath at 60 ℃ to obtain sol; wherein the molar concentration of the lithium hydroxide is 0.1mol/L, and the mass concentration of the ethylene diamine tetraacetic acid is 1%;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling after 20 seconds, drying for 1 hour at 80 ℃ in a pouring drying oven, and presintering for 3 hours at 350 ℃ to obtain a layer of lithium titanate precursor film;
(4) and (4) calcining the lithium titanate precursor film obtained in the step (3) for 5 hours at 700 ℃ in an air atmosphere to obtain the lithium titanate film cathode material.
The lithium titanate film negative electrode material prepared in the comparative example has the specific discharge capacity of 160.12mAh/g at the multiplying power of 0.2C, the specific discharge capacity of 156.32mAh/g at the multiplying power of 2C, and the capacity retention rate after 50 cycles is 97.11%.
FIG. 2 is a cycle performance diagram of lithium titanate thin film anode materials obtained in example 1 and a comparative example at 0.2C, 1C and 2C multiplying power; the discharge specific capacity of the ytterbium silicate-coated lithium titanate film negative electrode material obtained by modification in example 1 at a rate of 0.2C is 164.89mAh/g, the discharge specific capacity at a rate of 2C is 161.46mAh/g, and the capacity retention rate after 50 cycles is 98.97%; the lithium titanate film negative electrode material prepared in the comparative example has the specific discharge capacity of 160.12mAh/g at the multiplying power of 0.2C, the specific discharge capacity of 156.32mAh/g at the multiplying power of 2C, and the capacity retention rate after 50 cycles is 97.11%; this illustrates ytterbium silicate (YB)2SiO5) Can be effectively coated on the surface of the lithium titanate film, and shows higher electrochemical activity and excellent electrochemical performance.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (10)
1. A modification method of a lithium titanate negative electrode material of a lithium ion battery is characterized by comprising the following steps: the method specifically comprises the following steps:
(1) soaking the pure titanium sheet in an acid solution at normal temperature and pressure for 10-30h, taking out, cleaning until the pH value is 6-8, and then drying and calcining to obtain a titanium dioxide film;
(2) adding a chelating agent into an absolute ethyl alcohol solution containing a lithium source, and stirring in a water bath at 60-80 ℃ to obtain sol;
(3) immersing the titanium dioxide film obtained in the step (1) into the sol obtained in the step (2), slowly pulling, and then sequentially drying and presintering to obtain a layer of lithium titanate precursor film;
(4) taking the lithium titanate precursor film obtained in the step (3) as a matrix, and preparing a coating layer of ytterbium silicate on the surface of the matrix by adopting a plasma spraying-physical vapor deposition technology in a rotating manner at 40-60r/min, wherein the method comprises the following specific steps: fixing the layer of lithium titanate precursor film obtained in the step (3) on a tool, performing ultrasonic degreasing and cleaning, then placing the film on a spraying clamp, preheating the matrix to 600-800 ℃ through plasma, and finally spraying ytterbium silicate powder to obtain a lithium titanate precursor film coated by ytterbium silicate;
(5) and (5) calcining the lithium titanate precursor film coated with the ytterbium silicate obtained in the step (4) to obtain the lithium titanate film negative electrode material coated with the ytterbium silicate.
2. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: repeating the steps (1) to (3) to obtain a lithium titanate precursor film with a preset number of layers, and then taking the obtained lithium titanate precursor film with the preset number of layers as the matrix in the step (4).
3. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (1), before the pure titanium sheet is soaked in the acid solution, the pure titanium sheet is polished to be smooth by abrasive paper, and then is subjected to ultrasonic cleaning and drying by sequentially using acetone, absolute ethyl alcohol and deionized waterCleaning; the acidic solution is selected from HCL solution and HNO3Solutions or H2SO4The molar concentration of the acid solution is 6-10 mol/L; soaking the pure titanium sheet in an acid solution, then cleaning the pure titanium sheet with deionized water until the pH value is 6-8, drying the pure titanium sheet in a drying box at 80-100 ℃ for 1-10h, and then calcining the pure titanium sheet at 650 ℃ for 3-5h to obtain the titanium dioxide film.
4. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (2), the molar concentration of the lithium source in the absolute ethyl alcohol solution containing the lithium source is 0.1-3mol/L, and the lithium source is one or a mixture of several of lithium hydroxide, lithium acetate and lithium nitrate; the mass concentration of the chelating agent is 1-15%, and the chelating agent is one or a mixture of more of ethylenediamine tetraacetic acid, oxalic acid and citric acid.
5. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (2), the stirring time in water bath is 2-12 h.
6. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (3), the titanium dioxide film is immersed into the sol, slowly pulled after 20 seconds, put into a drying box to be dried for 1-10 hours at the temperature of 80-100 ℃, and then presintered for 3-5 hours at the temperature of 350-450 ℃ to obtain a layer of lithium titanate precursor film.
7. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (4), the lithium titanate precursor film is fixed on a tool, ultrasonic degreasing is sequentially carried out on the matrix by using kerosene, acetone and alcohol, and the matrix is placed on a spraying fixture after being cleaned by deionized water.
8. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (4), a double-pipe spray gun is adopted to spray the matrix, before spraying, the spraying vacuum tank is pumped to 150-.
9. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (4), the mass percentage of ytterbium silicate coated on the surface of the lithium titanate precursor film is 1-5%.
10. The method for modifying the lithium titanate negative electrode material of the lithium ion battery according to claim 1, characterized in that: in the step (5), the lithium titanate precursor film coated with ytterbium silicate is placed in an air atmosphere and calcined at the temperature of 700-900 ℃ for 5-10h to obtain the lithium titanate film coated with ytterbium silicate.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103636035A (en) * | 2011-06-24 | 2014-03-12 | 旭硝子株式会社 | Method for manufacturing positive-electrode active material for lithium ion secondary cell |
| CN103682354A (en) * | 2012-09-18 | 2014-03-26 | 华为技术有限公司 | All-solid-state lithium ion battery composite electrode material and preparation method thereof and all-solid-state lithium ion battery |
| CN103746103A (en) * | 2014-01-15 | 2014-04-23 | 合肥国轩高科动力能源股份公司 | Preparation method for lithium titanate thin film |
| CN107293720A (en) * | 2017-06-28 | 2017-10-24 | 合肥国轩高科动力能源有限公司 | A kind of zirconium scandium composite oxides cladding lithium titanate anode material and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103636035A (en) * | 2011-06-24 | 2014-03-12 | 旭硝子株式会社 | Method for manufacturing positive-electrode active material for lithium ion secondary cell |
| CN103682354A (en) * | 2012-09-18 | 2014-03-26 | 华为技术有限公司 | All-solid-state lithium ion battery composite electrode material and preparation method thereof and all-solid-state lithium ion battery |
| CN103746103A (en) * | 2014-01-15 | 2014-04-23 | 合肥国轩高科动力能源股份公司 | Preparation method for lithium titanate thin film |
| CN107293720A (en) * | 2017-06-28 | 2017-10-24 | 合肥国轩高科动力能源有限公司 | A kind of zirconium scandium composite oxides cladding lithium titanate anode material and preparation method thereof |
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