CN112978703A - Lithium ion battery positive electrode material with carbon fluoride-coated lithium manganese phosphate derived from black talc and preparation method thereof - Google Patents
Lithium ion battery positive electrode material with carbon fluoride-coated lithium manganese phosphate derived from black talc and preparation method thereof Download PDFInfo
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Abstract
The invention provides a lithium ion battery anode material with carbon fluoride-coated lithium manganese phosphate derived from black talc and a preparation method thereof, wherein the lithium ion battery anode material with carbon fluoride-coated lithium manganese phosphate derived from black talc is prepared by the following method: crushing and ball-milling a black talc mineral material from Guangfeng area in Jiangxi, preparing a thin black talc nanosheet in an ultrasonic stripping mode, treating the black talc nanosheet by a three-time acid method to obtain derived carbon fluoride, and on the other hand, synthesizing lithium manganese phosphate by a solvothermal method, coating the carbon fluoride on the surface of lithium manganese phosphate particles, so as to synthesize a novel carbon fluoride/lithium manganese phosphate anode material; the anode material prepared by the method has high specific capacity and good rate capability.
Description
Technical Field
The invention belongs to the technical field of inorganic energy storage materials, and particularly relates to a black talc derived carbon fluoride coated lithium manganese phosphate lithium ion battery anode material and a preparation method thereof.
Background
Generally, carbon fluoride materials are obtained by direct reaction of fluorine gas with carbon materials at high temperatures, and higher fluorine contents (0.5) can be obtained at higher reaction temperatures<x<1) However, too high a temperature causes decomposition of the carbon fluoride, and therefore the reaction temperature is usually less than 600 ℃. Generally speaking CFxThe F content in (A) is generally not more than 1, but when we use amorphous carbon and highly disordered carbon materials, the F content may exceed 1, giving CF2And CF3Etc., but these functional groups are less reactive than CF. Thus, graphite materials or other highly graphitized materials are more suitable as raw materials for preparing carbon fluoride.
Black talc is a layered clay mineral, has huge reserves of 10 hundred million tons in China Jiangxi Guangfeng, and occupies the first place of the world, and the main chemical component of the black talc is Mg3(Si4O10)(OH)2Since the graphene-like organic material is contained, the material is black or grayish black. The reason why the value of d of the (001) plane diffraction peak of the black talc is larger than that of the white talc is that "extra layer-like graphene carbon layers" appear between the crystal layers of the black talc. Therefore, black talc can be used as a raw material for synthesizing a carbon fluoride material.
LiMnPO4The material is a natural mineral or artificially synthesized ternary lithium battery electrode material. Lithium manganese phosphate has an olivine structure, typically orthorhombic (space group: Pmnb), has a transformation point of about 760 degrees celsius, and maintains its crystal structure at higher temperatures. The one-dimensional channel can enable lithium ions to be inserted and extracted, so that the lithium ion battery anode material can be used as a lithium ion battery anode material. The density of the lithium manganese phosphate is about 3.50 times of that of water, the electric conductivity of the lithium manganese phosphate is extremely low and is 2 to 3 orders of magnitude lower than that of lithium iron phosphate, and the lithium manganese phosphate mineral exists stably in nature. Lithium manganese phosphate has a specific capacity of 171mAh/g and a discharge plateau (vs Li/Li +) of around 4.1V,this also makes lithium manganese phosphate an ideal material for the new generation of lithium ion power cells.
Disclosure of Invention
The invention aims to provide a lithium ion battery anode material with carbon fluoride coated lithium manganese phosphate derived from black talc and a preparation method thereof.
The technical scheme of the invention is as follows:
a lithium ion battery anode material with carbon fluoride coated lithium manganese phosphate derived from black talc is prepared by the following steps:
(1) crushing, ball-milling and ultrasonically stripping a black talc mineral raw material to obtain a black talc nanosheet;
the black talc mineral raw material is from Guangfeng area in Jiangxi; ball-milling the black talc mineral raw material by using a ball mill, and ultrasonically stripping for 0.5-1 h under a 40kHz ultrasonic instrument to obtain a black talc nanosheet; the particle size of the obtained black talc nano sheet is 100-300 nm, preferably 100-200 nm;
(2) acid treatment of black talc nanoplatelets was performed in three times: removing carbonate by adopting hydrochloric acid treatment for the first time; after centrifugation, removing all silicon substances by hydrofluoric acid treatment for the second time; centrifuging again, treating with nitric acid for the third time, and centrifuging and drying to obtain a carbon fluoride material;
in the first acid treatment, the concentration of hydrochloric acid is 5-10M, the time is 2-8 h, and the temperature is room temperature (20-30 ℃); preferably, the concentration of hydrochloric acid is 5-8M, the time is 2-6 h, and the temperature is room temperature;
in the second acid treatment, the concentration of hydrofluoric acid is 2-6M, the time is 10-15 h, and the temperature is 20-80 ℃; preferably, the concentration of hydrofluoric acid is 3-6M, the time is 12-15 h, and the temperature is 50-80 ℃;
in the third acid treatment, the concentration of nitric acid is 2-6M, the time is 10-25 h, and the temperature is 20-50 ℃; preferably, the concentration of nitric acid is 3-6M, the time is 20-25 h, and the temperature is 30-50 ℃;
(3) mixing manganese salt, phosphoric acid, lithium hydroxide and a reaction solvent, carrying out solvothermal reaction for 2-10 h (preferably 6-10 h) at 120-200 ℃ (preferably 150-200 ℃), and then carrying out centrifugal drying to obtain lithium manganese phosphate;
the mass ratio of the manganese salt to the phosphoric acid to the lithium hydroxide is 1: 1-2: 1-3, preferably 1: 1-1.5: 1-3;
the manganese salt is selected from manganese sulfate, manganese nitrate or manganese acetate, preferably manganese nitrate or manganese acetate;
the volume dosage of the reaction solvent is 50-70 mL/g, preferably 60mL/g, calculated by the mass of the manganese salt;
the reaction solvent is selected from ethylene glycol, isopropanol or glycerol, preferably ethylene glycol or isopropanol;
(4) mixing the carbon fluoride obtained in the step (2) with the lithium manganese phosphate obtained in the step (3), and calcining for 2-4 hours at 300-600 ℃ (preferably 400-600 ℃) to obtain the carbon fluoride-coated lithium manganese phosphate lithium ion battery anode material derived from black talc;
the mass ratio of the carbon fluoride to the lithium manganese phosphate is 1: 40-50, preferably 1: 42 to 50.
The carbon fluoride coated lithium manganese phosphate lithium ion battery cathode material derived from black talc can be applied to lithium ion batteries.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, the carbon fluoride derived from black talc is coated on the surface of lithium manganese phosphate particles for the first time, and the carbon fluoride is calcined at high temperature, so that fewer structural defects can be obtained in the process of converting the orbital hybridization of C from sp2-sp3, and the difference in structure can further cause the difference in electrochemical properties, thereby obtaining good conductivity. Therefore, the carbon fluoride coated lithium manganese phosphate particles can obviously improve the conductivity of the lithium manganese phosphate, and compared with the conventional lithium manganese phosphate material, the specific capacity of the lithium manganese phosphate can be improved by 30-50 mAh.g-1The highest value can reach 165.6mAh g-1Near theoretical capacity 171mAh g-1。
Drawings
FIG. 1 is a high-power transmission electron microscope image of a carbon fluoride-coated lithium manganese phosphate cathode material synthesized in example 1.
Fig. 2 charge and discharge curves for example 5 and the comparative example.
FIG. 3 test chart of AC impedance of example 5 and comparative example.
Detailed Description
The invention is further described below by means of specific examples, without the scope of protection of the invention being limited thereto.
Example 1
Crushing and ball-milling black talc mineral materials from Guangfeng areas in Jiangxi, ultrasonically stripping the crushed materials for 30 minutes by using an ultrasonic instrument (40kHz) to prepare thin black talc nanosheets, and then classifying and screening the thin black talc nanosheets with the average particle size of 300nm after the thin black talc nanosheets are measured by using a particle size analyzer. Carrying out acid treatment on the black talc nanosheets for three times, soaking the black talc nanosheets in 5M hydrochloric acid for the first time, and treating at room temperature for 2 hours to remove carbonate; after centrifugation, soaking the treated sample in 3M hydrofluoric acid for the second time, and treating at 50 ℃ for 12h to remove all silicon substances; and after centrifuging again, soaking the sample in 3M nitric acid for the third time, treating at 30 ℃ for 20h, and centrifugally drying to obtain the required carbon fluoride material. On the other hand, manganese lithium phosphate is synthesized by a solvothermal method, and manganese acetate, phosphoric acid and lithium hydroxide are mixed according to the weight ratio of 1: 1: 1 (the mass of manganese acetate is 2g) is mixed and added into 120ml of glycol solvent, the mixture is stirred evenly and put into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction, the reaction time is 2h, the temperature is 150 ℃, and after the reaction is finished, the required lithium manganese phosphate is obtained by centrifugal drying. And finally, mixing the synthesized carbon fluoride and lithium manganese phosphate according to the weight ratio of 1: and after 40 compounding, calcining for 2 hours at 300 ℃ to obtain the novel carbon fluoride/lithium manganese phosphate cathode material.
Constant current cyclic charge and discharge test
The charge and discharge test experiment can be used for detecting the charge and discharge specific capacity and the cycle performance of the electrode material of the lithium ion secondary battery, and is an important experimental method in the research of the performance of the electrode material. In the process of charging and discharging the battery, electrochemical parameters such as charging and discharging voltage, charging and discharging time, charging and discharging capacity and the like of the battery are measured. The cycle performance is also an important index for the anode material, and the battery with good cycle performance has less capacity decline, stable voltage characteristic and good repeatability after multiple charging and discharging cycles.
The capacity of the electrode material is divided into theoretical capacity and actual capacity, and the theoretical capacity is calculated according to the following formula:
wherein C is the theoretical capacity of the positive electrode material; e is the amount of charge of a charge; na is the Avogastron constant; m is the mass of the active species fully reacted; z is the number of electrons lost or gained by the electrode reaction; m is the formula weight of the active substance. LiMnPO4The theoretical capacity of the anode material is as follows: c (LiMnPO)4)＝171mAh g-1
In the actual test, the actual discharge specific capacity (C) of the positive electrode material is tested by constant current charging and dischargingo) Calculated according to the following formula:
in the formula: coThe actual specific discharge capacity of the anode material is generally mAh g-1(ii) a I represents a current (mA); t represents the time (h) from discharge to the end voltage; m represents the mass (g) of the active substance actually participating in the reaction.
In the experiment, a constant current cyclic charging and discharging method is adopted to test the specific capacity and the cyclic stability of the lithium battery, a charging and discharging test is carried out on a LAND battery testing system (CT2001A,5V/10mA) of Wuhan Jinnuo electronics Limited company, the voltage range is 2.5-4.2V, and the magnitude of charging and discharging current is represented by the charging and discharging multiplying power (C) (1C is 171mAh: g'). The charging and discharging process of the lithium battery in the experiment: firstly, setting the current according to different charge and discharge multiplying factors, firstly charging at constant current, switching to the discharge process after the equal voltage reaches 4.2V, and then discharging in the constant current mode, wherein the discharge current is the same as the charge current, and when the voltage of the battery is reduced to 2.5V, the discharge is automatically stopped, and then switching to the next cycle. And dividing the charge-discharge capacity by the mass of the positive electrode active substance to obtain the charge-discharge specific capacity of the positive electrode material. The ambient temperature for charging and discharging the laboratory battery was 20 ℃.
AC impedance testing
Ac impedance, also called electrochemical impedance spectroscopy, is an important tool for studying electrode process dynamics and electrode surface phenomena. A sine wave AC excitation signal is superposed on a given polarized current AC impedance test method, a small solution DC component or electrode potential is added, and after an electrochemical system reaches a stable state, the change relation of the potential of the measurement system to current and impedance is analyzed and measured, so that information about the electrochemical current, phase, time, reaction, ohmic resistance, kinetic parameters of an electrode process, a surface film layer and the like output in the system is obtained. The method can estimate the equivalent circuit of the electrode process and calculate the value of each element in the equivalent circuit in a simulation mode. The equivalent circuit refers to a circuit utilizing sums to simulate the electrochemical process of the electrode during the ac impedance characterization process. The equivalent circuit can be deduced according to the process characteristics of the electrode, and then the comparison is carried out according to the actually measured alternating current impedance diagram. Generally, parallel connection of elements is a process occurring in parallel in a system, and parallel connection of elements is a process occurring dimensionally in a system.
And taking the imaginary part of the impedance as a vertical coordinate and the real part as a horizontal coordinate to obtain a curve, namely a Niquist diagram. In a quasi-reversible electrode system, a charge mass transfer process and a transfer process jointly form an electrode process, concentration polarization and electrochemical polarization exist simultaneously, impedance spectrums of the two processes can appear in different frequency ranges, a characteristic spectrum straight line controlled by diffusion can appear in a low-frequency region, a characteristic impedance semicircle controlled by charge migration can appear in a high-frequency region, so that a complex plan view of impedance generally consists of a straight line in the low-frequency region and a semicircle in the high-frequency region, polarization impedance of electrode reaction is represented by the diameter of the semicircle, and Watbaug impedance caused by lithium ion diffusion is represented by the straight line. From the Watbaug impedance, the diffusion coefficient of lithium ions in the electrode can be calculated.
Tests prove that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 142.1mAh g-1And no obvious attenuation is generated in the process of 30 times of cyclic charge and discharge.
Example 2
Crushing and ball-milling black talc mineral materials from Guangfeng areas in Jiangxi, ultrasonically stripping the crushed materials for 30 minutes by using an ultrasonic instrument (40kHz) to prepare thin black talc nanosheets, and then classifying and screening the thin black talc nanosheets with the average particle size of 100nm after the thin black talc nanosheets are measured by using a particle size analyzer. Carrying out acid treatment on the black talc nanosheets for three times, soaking the black talc nanosheets in 5M hydrochloric acid for the first time, and treating at room temperature for 2 hours to remove carbonate; after centrifugation, soaking the treated sample in 3M hydrofluoric acid for the second time, and treating at 50 ℃ for 12h to remove all silicon substances; and after centrifuging again, soaking the sample in 3M nitric acid for the third time, treating at 30 ℃ for 20h, and centrifugally drying to obtain the required carbon fluoride material. On the other hand, manganese lithium phosphate is synthesized by a solvothermal method, and manganese acetate, phosphoric acid and lithium hydroxide are mixed according to the weight ratio of 1: 1: 1 (the mass of manganese acetate is 2g) is mixed and added into 120ml of glycol solvent, the mixture is stirred evenly and put into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction, the reaction time is 2h, the temperature is 150 ℃, and after the reaction is finished, the required lithium manganese phosphate is obtained by centrifugal drying. And finally, mixing the synthesized carbon fluoride and lithium manganese phosphate according to the weight ratio of 1: and after 40 compounding, calcining for 2 hours at 300 ℃ to obtain the novel carbon fluoride/lithium manganese phosphate cathode material.
Tests show that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 146.7mAh g-1And no obvious attenuation is generated in the process of 30 times of cyclic charge and discharge.
Example 3
Crushing and ball-milling black talc mineral materials from Guangfeng areas in Jiangxi, ultrasonically stripping the crushed materials for 30 minutes by using an ultrasonic instrument (40kHz) to prepare thin black talc nanosheets, and then classifying and screening the thin black talc nanosheets with the average particle size of 100nm after the thin black talc nanosheets are measured by using a particle size analyzer. Carrying out acid treatment on the black talc nanosheets for three times, soaking the black talc nanosheets in 10M hydrochloric acid for the first time, and treating at room temperature for 2 hours to remove carbonate; after centrifugation, soaking the treated sample in 6M hydrofluoric acid for the second time, and treating at 50 ℃ for 12h to remove all silicon substances; and after centrifuging again, soaking the sample in 6M nitric acid for the third time, treating at 30 ℃ for 20h, and centrifugally drying to obtain the required carbon fluoride material. On the other hand, manganese lithium phosphate is synthesized by a solvothermal method, and manganese acetate, phosphoric acid and lithium hydroxide are mixed according to the weight ratio of 1: 1: 1 (the mass of manganese acetate is 2g) is mixed and added into 120ml of glycol solvent, the mixture is stirred evenly and put into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction, the reaction time is 2h, the temperature is 150 ℃, and after the reaction is finished, the required lithium manganese phosphate is obtained by centrifugal drying. And finally, mixing the synthesized carbon fluoride and lithium manganese phosphate according to the weight ratio of 1: and after 40 compounding, calcining for 2 hours at 300 ℃ to obtain the novel carbon fluoride/lithium manganese phosphate cathode material.
Tests show that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 152.8mAh g-1And no obvious attenuation is generated in the process of 30 times of cyclic charge and discharge.
Example 4
Crushing and ball-milling black talc mineral materials from Guangfeng areas in Jiangxi, ultrasonically stripping the crushed materials for 30 minutes by using an ultrasonic instrument (40kHz) to prepare thin black talc nanosheets, and then classifying and screening the thin black talc nanosheets with the average particle size of 100nm after the thin black talc nanosheets are measured by using a particle size analyzer. Carrying out acid treatment on the black talc nanosheets for three times, soaking the black talc nanosheets in 10M hydrochloric acid for the first time, and treating at room temperature for 2 hours to remove carbonate; after centrifugation, soaking the treated sample in 6M hydrofluoric acid for the second time, and treating at 50 ℃ for 12h to remove all silicon substances; and after centrifuging again, soaking the sample in 6M nitric acid for the third time, treating at 30 ℃ for 20h, and centrifugally drying to obtain the required carbon fluoride material. On the other hand, manganese lithium phosphate is synthesized by a solvothermal method, and manganese acetate, phosphoric acid and lithium hydroxide are mixed according to the weight ratio of 1: 1: 2.5 (the mass of manganese acetate is 2g), mixing and adding the mixture into 120ml of glycol solvent, stirring the mixture evenly, putting the mixture into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction for 2 hours at the temperature of 150 ℃, and after the reaction is finished, carrying out centrifugal drying to obtain the required lithium manganese phosphate. And finally, mixing the synthesized carbon fluoride and lithium manganese phosphate according to the weight ratio of 1: after 50 compounding, calcining for 2h at 300 ℃ to obtain the novel carbon fluoride/lithium manganese phosphate anode material.
Tests show that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 155.3mAh g-1And no obvious attenuation is generated in the process of 30 times of cyclic charge and discharge.
Example 5
Crushing and ball-milling black talc mineral materials from Guangfeng areas in Jiangxi, ultrasonically stripping the crushed materials for 30 minutes by using an ultrasonic instrument (40kHz) to prepare thin black talc nanosheets, and then classifying and screening the thin black talc nanosheets with the average particle size of 100nm after the thin black talc nanosheets are measured by using a particle size analyzer. Carrying out acid treatment on the black talc nanosheets for three times, soaking the black talc nanosheets in 10M hydrochloric acid for the first time, and treating at room temperature for 2 hours to remove carbonate; after centrifugation, soaking the treated sample in 6M hydrofluoric acid for the second time, and treating at 50 ℃ for 12h to remove all silicon substances; and after centrifuging again, soaking the sample in 6M nitric acid for the third time, treating at 30 ℃ for 20h, and centrifugally drying to obtain the required carbon fluoride material. On the other hand, manganese lithium phosphate is synthesized by a solvothermal method, and manganese acetate, phosphoric acid and lithium hydroxide are mixed according to the weight ratio of 1: 1: 2.5 (the mass of manganese acetate is 2g), mixing and adding the mixture into 120ml of glycol solvent, stirring the mixture evenly, putting the mixture into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction for 2 hours at the temperature of 150 ℃, and after the reaction is finished, carrying out centrifugal drying to obtain the required lithium manganese phosphate. And finally, mixing the synthesized carbon fluoride and lithium manganese phosphate according to the weight ratio of 1: after being compounded by 45, the mixture is calcined for 3 hours at 550 ℃ to obtain the novel carbon fluoride/lithium manganese phosphate anode material.
Tests show that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 165.6mAh g-1And no obvious attenuation is generated in the process of 30 times of cyclic charge and discharge.
By comparing examples 4 and 5, it is found that the specific capacity is improved after high temperature heat treatment, because the C-F bond is closer to the covalent bond, the fluorine content is further improved, and the content of volatile fluoride is further reduced.
Comparative example
Synthesizing lithium manganese phosphate by a solvothermal method, and mixing manganese acetate, phosphoric acid and lithium hydroxide according to the weight ratio of 1: 1: 2.5 (the mass of manganese acetate is 2g), mixing and adding the mixture into 120ml of glycol solvent, stirring the mixture evenly, putting the mixture into a 200ml of polytetrafluoroethylene reaction kettle for solvothermal reaction for 2 hours at the temperature of 150 ℃, and after the reaction is finished, carrying out centrifugal drying to obtain the required lithium manganese phosphate.
Tests show that the specific capacity of the synthesized carbon fluoride coated lithium manganese phosphate anode material is 112.2mAh g-1At 10 cyclesThe ring begins to decay after charging and discharging.
Through comparison, the manganese phosphate lithium material coated by the carbon fluoride has better conductivity, higher specific capacity and more stable electrochemical performance.
Claims (6)
1. The lithium ion battery positive electrode material with carbon fluoride-coated lithium manganese phosphate derived from black talc is characterized by being prepared by the following method:
(1) crushing, ball-milling and ultrasonically stripping a black talc mineral raw material to obtain a black talc nanosheet;
(2) acid treatment of black talc nanoplatelets was performed in three times: removing carbonate by adopting hydrochloric acid treatment for the first time; after centrifugation, removing all silicon substances by hydrofluoric acid treatment for the second time; centrifuging again, treating with nitric acid for the third time, and centrifuging and drying to obtain a carbon fluoride material;
in the first acid treatment, the concentration of hydrochloric acid is 5-10M, the time is 2-8 h, and the temperature is room temperature;
in the second acid treatment, the concentration of hydrofluoric acid is 2-6M, the time is 10-15 h, and the temperature is 20-80 ℃;
in the third acid treatment, the concentration of nitric acid is 2-6M, the time is 10-25 h, and the temperature is 20-50 ℃;
(3) mixing manganese salt, phosphoric acid, lithium hydroxide and a reaction solvent, carrying out solvothermal reaction for 2-10 h at 120-200 ℃, and then carrying out centrifugal drying to obtain lithium manganese phosphate;
the mass ratio of the manganese salt to the phosphoric acid to the lithium hydroxide is 1: 1-2: 1-3;
(4) mixing the carbon fluoride obtained in the step (2) with the lithium manganese phosphate obtained in the step (3), and calcining at 300-600 ℃ for 2-4 h to obtain the carbon fluoride-coated lithium manganese phosphate lithium ion battery anode material derived from the black talc;
the mass ratio of the carbon fluoride to the lithium manganese phosphate is 1: 40 to 50.
2. The lithium ion battery cathode material of carbon fluoride-coated lithium manganese phosphate derived from black talc according to claim 1, wherein in step (1), the black talc mineral raw material is ball-milled by a ball mill, and is ultrasonically stripped for 0.5-1 h under a 40kHz ultrasonic instrument to obtain a black talc nanosheet; the particle size of the obtained black talc nano sheet is 100-300 nm.
3. The black talc-derived carbon fluoride-coated lithium manganese phosphate lithium ion battery positive electrode material as claimed in claim 1, wherein in the step (2), in the first acid treatment, the concentration of hydrochloric acid is 5-8M, the time is 2-6 h, and the temperature is room temperature; in the second acid treatment, the concentration of hydrofluoric acid is 3-6M, the time is 12-15 h, and the temperature is 50-80 ℃; in the third acid treatment, the concentration of nitric acid is 3-6M, the time is 20-25 h, and the temperature is 30-50 ℃.
4. The black talc-derived carbon fluoride-coated lithium manganese phosphate positive electrode material for lithium ion batteries according to claim 1, wherein in step (3), the manganese salt is selected from manganese sulfate, manganese nitrate or manganese acetate.
5. The black talc-derived carbon fluoride-coated lithium manganese phosphate lithium ion battery positive electrode material according to claim 1, wherein in step (3), the reaction solvent is selected from ethylene glycol, isopropanol or glycerol.
6. The black talc-derived carbon fluoride-coated lithium manganese phosphate lithium ion battery positive electrode material according to claim 1, wherein in the step (3), the volume usage amount of the reaction solvent is 50-70 mL/g based on the mass of the manganese salt.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113809306A (en) * | 2021-09-17 | 2021-12-17 | 中国科学院广州地球化学研究所 | Method for preparing silicon-carbon nano composite material by using black talc, product and application |
| CN115536033A (en) * | 2022-08-16 | 2022-12-30 | 浙江工业大学 | Preparation method of ultrathin black talc nanosheet |
| CN117049524A (en) * | 2023-10-12 | 2023-11-14 | 中南大学 | Method for extracting graphene-like material from black talcum and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102186768A (en) * | 2008-10-22 | 2011-09-14 | 株式会社Lg化学 | Lithium iron phosphate having an olivine structure, and preparation method thereof |
| CN102583298A (en) * | 2012-02-18 | 2012-07-18 | 无锡合志科技有限公司 | Preparation method of lithium iron phosphate compounded by graphite fluoride as cathode material of secondary lithium battery |
| CN103904321A (en) * | 2014-03-31 | 2014-07-02 | 华南理工大学 | High-temperature solid-phase preparation method of lithium ion battery negative electrode material |
| CN109286006A (en) * | 2018-09-18 | 2019-01-29 | 华北电力大学 | A kind of preparation method being fluorinated carbon coating nickel-cobalt-manganternary ternary anode material |
-
2021
- 2021-02-08 CN CN202110174831.0A patent/CN112978703A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102186768A (en) * | 2008-10-22 | 2011-09-14 | 株式会社Lg化学 | Lithium iron phosphate having an olivine structure, and preparation method thereof |
| CN102583298A (en) * | 2012-02-18 | 2012-07-18 | 无锡合志科技有限公司 | Preparation method of lithium iron phosphate compounded by graphite fluoride as cathode material of secondary lithium battery |
| CN103904321A (en) * | 2014-03-31 | 2014-07-02 | 华南理工大学 | High-temperature solid-phase preparation method of lithium ion battery negative electrode material |
| CN109286006A (en) * | 2018-09-18 | 2019-01-29 | 华北电力大学 | A kind of preparation method being fluorinated carbon coating nickel-cobalt-manganternary ternary anode material |
Non-Patent Citations (1)
| Title |
|---|
| PENG FAN ET AL: "Excellent electrochemical properties of graphene-like carbon obtained from acid-treating natural black talc as Li-ion battery anode", 《ELECTROCHIMICA ACTA》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113809306A (en) * | 2021-09-17 | 2021-12-17 | 中国科学院广州地球化学研究所 | Method for preparing silicon-carbon nano composite material by using black talc, product and application |
| CN115536033A (en) * | 2022-08-16 | 2022-12-30 | 浙江工业大学 | Preparation method of ultrathin black talc nanosheet |
| CN115536033B (en) * | 2022-08-16 | 2024-02-13 | 浙江工业大学 | Preparation method of ultrathin black talcum nano-sheet |
| CN117049524A (en) * | 2023-10-12 | 2023-11-14 | 中南大学 | Method for extracting graphene-like material from black talcum and application thereof |
| CN117049524B (en) * | 2023-10-12 | 2024-01-23 | 中南大学 | Method for extracting graphene-like material from black talcum and application thereof |
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