CN109599544B - Lithium vanadium phosphate/carbon composite cathode material and preparation method thereof - Google Patents

Lithium vanadium phosphate/carbon composite cathode material and preparation method thereof Download PDF

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CN109599544B
CN109599544B CN201811467104.8A CN201811467104A CN109599544B CN 109599544 B CN109599544 B CN 109599544B CN 201811467104 A CN201811467104 A CN 201811467104A CN 109599544 B CN109599544 B CN 109599544B
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CN109599544A (en
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李娜丽
崔旭梅
张雪峰
同艳维
弋大为
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Panzhihua University
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Abstract

The invention relates to Li3V2(PO4)3a/C composite anode material and a preparation method thereof, belonging to Li3V2(PO4)3The preparation field of the/C composite anode material. Li3V2(PO4)3The preparation method of the/C material comprises the following steps: weighing a compound containing lithium, vanadium, phosphate radical, nitrate radical and organic compound; dissolving the compound in water, and then heating and stirring to obtain dark blue gel; placing the gel in an environment with the temperature being raised to 750-900 ℃ in advance, and burning the gel for 10-40min to obtain a black precursor; finally adding an organic carbon source, mixing the organic carbon source with the precursor uniformly, calcining the mixture for 2 to 4 hours at the temperature of 700 ℃ and 900 ℃ under the protection of inert gas, and naturally cooling the mixture to obtain Li3V2(PO4)3And C, a positive electrode material. Prepared Li3V2(PO4)3the/C anode material has the advantages of good electrochemical performance, short process flow, low cost and easy industrial production.

Description

Lithium vanadium phosphate/carbon composite cathode material and preparation method thereof
Technical Field
The invention relates to a lithium vanadium phosphate/carbon composite anode material and a preparation method thereof, belonging to Li3V2(PO4)3The preparation field of the/C composite anode material.
Background
Lithium ion batteries have been widely used, including power batteries, due to their high specific energy, high operating voltage, long cycle life, no memory effect, and low pollution. However, with the rapid development of new energy automobiles, higher requirements are put on the performance of lithium ion batteries, and a more potential electrode cathode material is expected to be found. Of positive electrode materialsThe energy density is determined by the specific capacity and discharge voltage of the material, while the power density is determined by the rate capability of the material. Therefore, the specific capacity is high (197mAh/g), the platform voltage is high (3.6-4.5V vs. Li/Li)+) Monoclinic Li with good stability of circulating structure and the like3V2(PO4)3The anode material becomes a hot spot of energy material research. Currently restricting Li3V2(PO4)3One of the major obstacles to commercialization is the low electron conductivity due to its inherent structure (10)-8cm/s). Therefore, both at home and abroad for Li3V2(PO4)3The modification research mainly focuses on improving the electronic conductivity of the modified graphene, and the main ways of modification are as follows: coating or doping with highly conductive substances, ion doping and controlling the morphology of the sample by appropriate preparation methods.
The synthesis method of the lithium vanadium phosphate mainly comprises a solid phase method, a sol-gel method and the like, the solid phase method has a simple preparation process, the production conditions are easy to control, and the method is the preferred method for industrial production. However, the particle uniformity of the material prepared by the method is poor, and the morphology and the particle size of the material are difficult to control. The sol-gel method can realize uniform mixing on the molecular level, the obtained sample has low calcining temperature, small particle size and uniform distribution, the reaction is easy to control, the equipment is simple, but the shrinkage is large in the drying process, the synthesis period is too long, the sol-gel method is not suitable for industrial production, the material has irregular shape and is easy to agglomerate. The combustion method is characterized in that the self-generated heat and the self-conduction action of the chemical and physical reaction heat between the raw materials participating in the reaction are used for reacting to generate a product, the process is simple, the product performance is good, the preparation cost is low, and the like, so that the combustion method gradually becomes an excellent preparation method with the potential of industrial production, and the combustion method has the defects that the reaction process is violent and the granularity of the product is not easy to control. The combination of the sol-gel method and the combustion method can avoid the defects of the sol-gel method and the combustion method, develops the respective advantages of the sol-gel method and the combustion method, and is a convenient and practical new method for preparing the nano material. Zhang L, and the like, and a porous LVP/C composite cathode material is prepared by a sol-gel combustion method, and the results show that the material shows excellent rate capability due to a special porous structureCan be used. Ou et al NH4NO3Synthesis of submicron porous Li by sol-gel combustion method as additive3V2(PO4)3the/C composite material has excellent electrochemical performance, but the sintering time of the method is 6 hours, and if the sintering time is further shortened, such as when the sintering time is 4 hours, the reaction is incomplete, the crystallinity is poor, the crystal form is incomplete, and the electrochemical performance is poor. Therefore, the technology has the defects of long final solid-phase sintering time and overlong synthesis period, and is not suitable for industrial production.
Disclosure of Invention
The first technical problem to be solved by the invention is to provide Li with short synthesis period3V2(PO4)3A preparation method of the/C composite material.
Li3V2(PO4)3The preparation method of the/C composite positive electrode material comprises the following steps:
a. respectively weighing a lithium-containing compound, a vanadium-containing compound and a phosphate radical-containing compound according to the molar ratio of lithium to vanadium to phosphate radical of 3:2: 3; respectively weighing an organic compound and a nitrate-containing compound;
wherein the organic compound and the nitrate radical-containing compound are used in amounts satisfying the following conditions:
the molar ratio of the metal ions to the carbon to the nitrate is 1: 3-12: 0.3-1.2, and the molar ratio of the carbon to the nitrate is not less than 10; the carbon is carbon in an organic compound; the metal ions are the sum of metal ions in lithium ions, vanadium ions, phosphate radical-containing compounds and nitrate radical-containing compounds; the nitrate is the sum of nitrate in a nitrate-containing compound, a lithium-containing compound and a vanadium-containing compound;
b. dissolving all the weighed compounds in water, wherein the water amount is 3-8 times of the total weight of the compounds, heating to 80-100 ℃, and stirring for 1-3 hours under heat preservation to obtain dark blue gel;
c. putting the dark blue gel in an environment with the temperature pre-raised to 750-900 ℃, and burning for 10-40min to obtain a black precursor;
d. weighing an organic carbon source according to the weight of the organic carbon source which is 5-20% of that of the black precursor, crushing and uniformly mixing the precursor and the organic carbon source, calcining at 700-900 ℃ for 2-4 hours under the protection of inert gas, and naturally cooling to obtain Li3V2(PO4)3the/C composite cathode material.
Preferably, the lithium-containing compound is at least one of lithium hydroxide, lithium acetate, lithium carbonate and lithium nitrate; the vanadium-containing compound is at least one of vanadium pentoxide and ammonium metavanadate.
Preferably, the phosphate-containing compound is at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate, phosphoric acid and lithium dihydrogen phosphate.
Preferably, the nitrate-containing compound is at least one of ammonium nitrate and lithium nitrate.
Preferably, the organic compound is at least one of citric acid, urea, aspartic acid, tartaric acid, salicylic acid, ethylene glycol and ascorbic acid.
Preferably, the inert gas is Ar gas or N2And (4) qi.
Preferably, in step d, the organic carbon source is at least one of citric acid, glucose, stearic acid and sucrose.
Preferably, the molar ratio of metal ion, carbon to nitrate is 1:10.2: 0.3.
Preferably, in step c: heating to 750-850 ℃; preferably, the temperature is raised to 850 ℃.
Preferably, in step d, the calcination is carried out for 3 hours.
The invention also provides Li3V2(PO4)3a/C composite positive electrode material made of said Li3V2(PO4)3The preparation method of the/C composite anode material.
The invention has the beneficial effects that:
1. the invention greatly shortens the final solid phase sintering time by improving the ignition temperature, thereby shortening the synthesis period of the anode material and being beneficial to industrial production.
2. The invention does not need to be dried before ignition, and the ignition can be directly carried out, thereby saving the process steps and reducing the cost.
3. Li prepared by the invention3V2(PO4)3the/C anode material has good crystallinity and perfect crystal growth.
4. Li prepared by the invention3V2(PO4)3the/C positive electrode material has good electrochemical performance and excellent cycle performance, and the first charge specific capacity is 130.9 mAh.g within the charge-discharge range of 3-4.3V under the charge-discharge condition of 0.2C-1The first discharge specific capacity is up to 129.5 mAh.g-1The first coulombic efficiency is 98.93%, and the capacity retention rate after 20 cycles is 98.07%; under the charge-discharge condition of 2C, the first discharge specific capacity is up to 124.6 mAh.g-1And under the condition of charging and discharging of 5C, the first discharge specific capacity is as high as 120.8 mAh.g-1。
Drawings
FIG. 1 shows Li prepared in example 13V2(PO4)3XRD pattern of the/C sample.
FIG. 2 shows Li prepared in example 23V2(PO4)3XRD pattern of the/C sample.
FIG. 3 shows Li prepared in example 33V2(PO4)3XRD pattern of the/C sample.
FIG. 4 shows Li prepared in example 13V2(PO4)3The first charge-discharge curve of the/C sample under the voltage range of 3.0-4.3V and 0.2C multiplying power.
FIG. 5 shows Li prepared in example 23V2(PO4)3The first charge-discharge curve of the/C sample under the voltage range of 3.0-4.3V and 0.2C multiplying power.
FIG. 6 shows Li prepared in example 33V2(PO4)3The first charge-discharge curve of the/C sample under the voltage range of 3.0-4.3V and 0.2C multiplying power.
FIG. 7 shows Li prepared in example 23V2(PO4)3The cycle performance curve of the/C sample under the voltage range of 3.0-4.3V and the multiplying power of 0.2C, 2C and 5C.
FIG. 8 shows Li obtained in examples 4 to 73V2(PO4)3XRD pattern of/C precursor.
FIG. 9 shows Li obtained in examples 4 to 73V2(PO4)3Cell cycle plot of the precursor of/C.
Detailed Description
The first technical problem to be solved by the invention is to provide Li with short synthesis period3V2(PO4)3A preparation method of the/C composite material.
Li3V2(PO4)3The preparation method of the/C composite positive electrode material comprises the following steps:
a. respectively weighing a lithium-containing compound, a vanadium-containing compound and a phosphate radical-containing compound according to the molar ratio of lithium to vanadium to phosphate radical of 3:2: 3; respectively weighing an organic compound and a nitrate-containing compound;
wherein the organic compound and the nitrate radical-containing compound are used in amounts satisfying the following conditions:
the molar ratio of the metal ions to the carbon to the nitrate is 1: 3-12: 0.3-1.2, and the molar ratio of the carbon to the nitrate is not less than 10; the carbon is carbon in an organic compound; the metal ions are the sum of metal ions in lithium ions, vanadium ions, phosphate radical-containing compounds and nitrate radical-containing compounds; the nitrate is the sum of nitrate in a nitrate-containing compound, a lithium-containing compound and a vanadium-containing compound;
b. dissolving all the weighed compounds in water, wherein the water amount is 3-8 times of the total weight of the compounds, heating to 80-100 ℃, and stirring for 1-3 hours under heat preservation to obtain dark blue gel; all the compounds are the lithium-containing compound, the vanadium-containing compound, the phosphate radical-containing compound, the organic compound and the nitrate radical-containing compound which are weighed in the step a;
c. putting the dark blue gel in an environment with the temperature pre-raised to 750-900 ℃, and burning for 10-40min to obtain a black precursor; the specific operation of this step may be: placing the dark blue gel in a crucible, and then placing the crucible in a muffle furnace which is preheated to 750-900 ℃ for operation; the temperature of 750-900 ℃ is the ignition temperature of the invention.
d. Weighing an organic carbon source according to the weight of the organic carbon source which is 5-20% of that of the black precursor, crushing and uniformly mixing the precursor and the organic carbon source, calcining at 700-900 ℃ for 2-4 hours under the protection of inert gas, and naturally cooling to obtain Li3V2(PO4)3the/C composite cathode material.
The invention needs to add nitrate-containing compound to provide nitrate, and the nitrate is used as an oxidant to generate oxidation reaction to generate NO2NO or N2And the lithium vanadium phosphate particles are made porous.
The molar ratio of carbon to nitrate needs to be not less than 10, and if the molar ratio is less than 10, LiVOPO is generated4。
The purpose of adding the organic compound is to provide a carbon source and act as a complexing agent and a reducing agent.
In the step c, the ignition temperature needs to be 750-900 ℃ and lower than 750 ℃, and vanadium lithium phosphate cannot be obtained or only a small amount of vanadium lithium phosphate can be obtained; above 900 ℃, the generated lithium vanadium phosphate crystal grains are relatively coarse, and the electrochemical performance is poor.
Because the invention adopts higher ignition temperature, the obtained gel can be directly ignited without being dried first, and the operation does not influence the performance of the product.
Preferably, the lithium-containing compound is at least one of lithium hydroxide, lithium acetate, lithium carbonate and lithium nitrate; the vanadium-containing compound is at least one of vanadium pentoxide and ammonium metavanadate.
Preferably, the phosphate-containing compound is at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate, phosphoric acid and lithium dihydrogen phosphate.
Preferably, the nitrate-containing compound is at least one of ammonium nitrate and lithium nitrate.
Preferably, the organic compound is at least one of citric acid, urea, aspartic acid, tartaric acid, salicylic acid, ethylene glycol and ascorbic acid.
Preferably, the inert gas is Ar gas or N2And (4) qi.
Preferably, in step d, the organic carbon source is at least one of citric acid, glucose, stearic acid and sucrose.
Preferably, the molar ratio of metal ion, carbon to nitrate is 1:10.2: 0.3. The material prepared by the proportion has good electrochemical performance.
In order to improve the crystallinity of the crystal of the material and improve the electrochemical properties of the material, preferably, in step c: heating to 750-850 ℃; preferably, the temperature is raised to 850 ℃ in which case Li is obtained3V2(PO4)3The crystallinity of the/C precursor is best, the crystal form growth is perfect, and the electrochemical performance is best.
Preferably, in step d, the calcination is carried out for 3 hours. At this firing time, the resulting cell performed best electrochemically.
The invention also provides Li3V2(PO4)3a/C composite positive electrode material made of said Li3V2(PO4)3The preparation method of the/C composite anode material.
The following examples are provided to further illustrate the embodiments of the present invention and are not intended to limit the scope of the present invention.
Example 1 preparation of Li3V2(PO4)3/C composite positive electrode material
a. 23.641g of citric acid was dissolved in 200g of deionized water, and 3.509g of NH was added4VO3、1.888gLiOH·H2O and 5.176gNH4H2PO4Adding into citric acid solution, stirring to dissolve, adding 0.931g ethylene glycol and 1.801g NH4NO3The solution was then evaporated at 80 ℃ with stirring for 1.5h to a dark blue gel.
b. The dark blue gel was transferred to a crucible and placed in a muffle furnace preheated to 850 deg.CIt was burnt for 20min to obtain black Li3V2(PO4)3and/C precursor.
c. Weighing an organic carbon source citric acid according to the weight of the organic carbon source which is 10 percent of that of the black precursor, crushing and uniformly mixing the precursor and the organic carbon source, calcining for 2 hours at 850 ℃ under the protection of inert gas, and naturally cooling to obtain Li3V2(PO4)3the/C composite cathode material.
Li prepared in this example3V2(PO4)3The X-ray diffraction pattern of the/C composite positive electrode material is shown in figure 1, and the figure shows that the product has no impurity phase and is pure-phase monoclinic system Li3V2(PO4)3。
Example 2
Li was obtained by changing the calcination time of only step c to 3 hours on the basis of example 13V2(PO4)3the/C composite cathode material. Li prepared in this example3V2(PO4)3The X-ray diffraction pattern of the/C composite positive electrode material is shown in figure 2, and the figure shows that the product has no impurity phase and is pure-phase monoclinic Li3V2(PO4)3。
Example 3
Li was obtained by changing the calcination time of only step c to 4 hours on the basis of example 13V2(PO4)3the/C composite cathode material. Li prepared in this example3V2(PO4)3The X-ray diffraction pattern of the/C composite positive electrode material is shown in figure 3, and the figure shows that the product has no impurity phase and is pure-phase monoclinic Li3V2(PO4)3。
Test example 1
Li prepared in examples 1 to 33VLi3V2(PO4)3320mg of/C composite positive electrode material and 40mg of acetylene black are ground in an agate grinding bowl for 30 min; putting 1g of polyvinylidene fluoride (PVDF, AR) into a 25mL reagent bottle and adding 19gN-The methylpyrrolidone (NMP, AR) is stirred and dissolved to prepare a PVDF-NMP solution with the mass fraction of 5%. And adding the mixture of the active substance and the acetylene black into a small weighing bottle, adding 800mg of 5% (mass fraction) PVDF-NMP solution, and finally placing the small weighing bottle on a magnetic stirrer to stir for 12 hours to prepare slurry. An aluminum foil 20 μm thick was placed on a smooth glass plate, and the slurry was coated on the aluminum foil with a coater, dried at 80 ℃ and then vacuum-dried at 120 ℃ for 8 hours. The electrode sheet was punched into a circular piece having a diameter of 14mm by a punch. A metal lithium sheet is taken as a negative electrode, a Celgard2500 film (made by America) is taken as a diaphragm, and 1mol/LLIPF is adopted6The electrolyte is prepared from the following components of/EC + DMC + EMC (volume ratio of 1:1: 1). Assembling into a CR2016 button cell in an argon atmosphere glove box, standing for 24h in a dry environment, and carrying out electrochemical performance test in a voltage range of 3.0-4.3V.
The first charge specific capacity of the sample prepared in example 1 at 0.2C rate was 131.6mAh g-1The specific discharge capacity is 122.1mAh g-1The first coulombic efficiency was 92.78%; the first charge-discharge curve is shown in figure 4.
The first charge specific capacity of the sample prepared in example 2 at 0.2C rate is 130.9mAh g-1The specific discharge capacity is 129.5mAh g-1The first coulombic efficiency is 98.93%, and the capacity retention rate after 20 cycles is 98.07%; the first charge specific capacity under the 2C multiplying power is 129.7mAh g-1The specific discharge capacity is 124.6 mAh.g-1The capacity retention rate after 20 times of circulation is 99.11%; the first charging specific capacity under 5C multiplying power is 128.3 mAh.g-1The specific discharge capacity is 120.8 mAh.g-1The capacity retention rate after 20 cycles was 98.18%. The first charge-discharge curve of 0.2C is shown in figure 5, and the cycle performance curves of 0.2C, 2C and 5C are shown in figure 7.
The first charge specific capacity of the sample prepared in example 3 at 0.2C rate was 129.8mAh g-1The specific discharge capacity is 122.7mAh g-1The first charge-discharge curve of 0.2C is shown in figure 6.
Example 4
a. 23.641g of citric acid was dissolved in 200g of deionized water, and 3.509g of NH was added4VO3、1.888gLiOH·H2O and 5.176gNH4H2PO4Adding into citric acid solution, stirring to dissolve, adding 0.931g ethylene glycol and 5.403g NH4NO3The solution was then evaporated at 80 ℃ with stirring for 1.5h to a dark blue gel.
b. Transferring the dark blue gel into a crucible, putting the crucible into a muffle furnace preheated to 750 ℃ in advance, and burning the crucible for 20min to obtain black Li3V2(PO4)3and/C precursor.
Example 5
On the basis of example 4, changing only the ignition temperature of step b to 800 ℃ gives black Li3V2(PO4)3and/C precursor.
Example 6
On the basis of example 4, changing only the ignition temperature of step b to 850 ℃ gives black Li3V2(PO4)3and/C precursor.
Example 7
On the basis of example 4, changing only the ignition temperature of step b to 900 ℃ gives black Li3V2(PO4)3and/C precursor.
Li obtained in examples 4 to 73V2(PO4)3The XRD pattern of the/C precursor is shown in figure 8;
as can be seen from FIG. 8, Li having a monoclinic structure can be generated when the temperature reaches 750 ℃ or higher3V2(PO4)3。
Li obtained in examples 4 to 73V2(PO4)3The cell cycle curves for the/C precursor are shown in FIG. 9.
With Li3V2(PO4)3And the/C precursor anode material is used as an anode active material and assembled into a button cell in an argon protective glove box, and the button cell is subjected to constant-current charge-discharge test. The electrolyte selected for the experiment is LiPF6The voltage range selected during the charge and discharge test of the organic solution is 3.0-4.3V, the multiplying power cycle test is 0.2C, and the cycle times are 20 times.
And (3) testing results:
the specific first discharge capacities of example 4, example 5, example 6 and example 7 were 109.3mAh g, respectively-1、95.6mAh·g-1、120.2mAh·g-1And 58.3mAh · g-1The specific discharge capacity after 20 cycles is 93.5mAh g-1、89.3mAh·g-1、104mAh·g-1And 57 mAh. g-1The capacity retention rates were 85.5%, 93.4%, 86.5%, and 97.8%, respectively.
As can be seen from test example 2, Li was obtained by comparing the ignition temperature3V2(PO4)3The performance of the/C precursor has an influence, and the crystal structure and the electrochemical performance of the/C precursor are influenced by over-high or over-low temperature.
In experiments, it is found that if the ignition temperature is lower than 750 ℃, lithium vanadium phosphate can not be obtained or only a small amount of lithium vanadium phosphate can be obtained, and if the ignition temperature is higher than 900 ℃, the generated lithium vanadium phosphate has larger crystal grains and poor electrochemical performance.

Claims (11)

1.Li3V2(PO4)3The preparation method of the/C composite positive electrode material is characterized by comprising the following steps of:
a. respectively weighing a lithium-containing compound, a vanadium-containing compound and a phosphate radical-containing compound according to the molar ratio of lithium to vanadium to phosphate radical of 3:2: 3; respectively weighing an organic compound and a nitrate-containing compound;
wherein the organic compound and the nitrate radical-containing compound are used in amounts satisfying the following conditions:
the molar ratio of the metal ions to the carbon to the nitrate is 1: 3-12: 0.3-1.2, and the molar ratio of the carbon to the nitrate is not less than 10; the carbon is carbon in an organic compound; the metal ions are the sum of metal ions in lithium ions, vanadium ions, phosphate radical-containing compounds and nitrate radical-containing compounds; the nitrate is the sum of nitrate in a nitrate-containing compound, a lithium-containing compound and a vanadium-containing compound;
b. dissolving all the weighed compounds in water, wherein the water amount is 3-8 times of the total weight of the compounds, heating to 80-100 ℃, and stirring for 1-3 hours under heat preservation to obtain dark blue gel;
c. putting the dark blue gel in an environment with the temperature pre-raised to 750-900 ℃, and burning for 10-40min to obtain a black precursor;
d. weighing an organic carbon source according to the weight of the organic carbon source being 5-20% of that of the black precursor, crushing and uniformly mixing the precursor and the organic carbon source, calcining at 700-900 ℃ for 2-3 hours under the protection of inert gas, and naturally cooling to obtain Li3V2(PO4)3the/C composite cathode material.
2. Li according to claim 13V2(PO4)3The preparation method of the/C composite positive electrode material is characterized in that the lithium-containing compound is at least one of lithium hydroxide, lithium acetate, lithium carbonate and lithium nitrate; the vanadium-containing compound is at least one of vanadium pentoxide and ammonium metavanadate.
3. Li according to claim 13V2(PO4)3The preparation method of the/C composite cathode material is characterized in that the phosphate radical-containing compound is at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate, phosphoric acid and lithium dihydrogen phosphate.
4. Li according to claim 13V2(PO4)3The preparation method of the/C composite cathode material is characterized in that the nitrate radical-containing compound is at least one of ammonium nitrate and lithium nitrate.
5. Li according to claim 13V2(PO4)3The preparation method of the/C composite cathode material is characterized in that the organic compound is at least one of citric acid, urea, aspartic acid, tartaric acid, salicylic acid, glycol and ascorbic acid.
6. Li according to claim 13V2(PO4)3The preparation method of the/C composite cathode material is characterized in that in the step d, the organic carbon source is at least one of citric acid, glucose, stearic acid and sucrose.
7. Li according to any one of claims 1 to 63V2(PO4)3The preparation method of the/C composite cathode material is characterized in that in the step a, the molar ratio of metal ions, carbon and nitrate radicals is 1:10.2: 0.3.
8. Li according to any one of claims 1 to 63V2(PO4)3The preparation method of the/C composite cathode material is characterized in that in the step C: heating to 750-850 ℃.
9. Li according to claim 83V2(PO4)3The preparation method of the/C composite cathode material is characterized in that in the step C: the temperature is raised to 850 ℃.
10. Li according to any one of claims 1 to 63V2(PO4)3The preparation method of the/C composite cathode material is characterized in that in the step d, the sintering is carried out for 3 hours.
11.Li3V2(PO4)3a/C composite positive electrode material comprising the Li according to any one of claims 1 to 103V2(PO4)3The preparation method of the/C composite anode material.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101841024A (en) * 2010-03-11 2010-09-22 南昌大学 Method for preparing cathode material lithium vanadium phosphate of lithium ion battery by using fast sol-gel method
CN102299332A (en) * 2011-07-25 2011-12-28 华南理工大学 Preparation method of porous lithium vanadium phosphate/carbon cathode material of lithium ion battery
CN103165890A (en) * 2013-03-26 2013-06-19 四川大学 Method for preparing lithium vanadium phosphate through sol-gel self-propagating combustion method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101841024A (en) * 2010-03-11 2010-09-22 南昌大学 Method for preparing cathode material lithium vanadium phosphate of lithium ion battery by using fast sol-gel method
CN102299332A (en) * 2011-07-25 2011-12-28 华南理工大学 Preparation method of porous lithium vanadium phosphate/carbon cathode material of lithium ion battery
CN103165890A (en) * 2013-03-26 2013-06-19 四川大学 Method for preparing lithium vanadium phosphate through sol-gel self-propagating combustion method

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