CN107611413B - Preparation method of titanium-doped lithium iron phosphate positive electrode material - Google Patents
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Abstract
The invention discloses a preparation method of a titanium-doped lithium iron phosphate anode material, which comprises the steps of taking a lithium source compound, a phosphorus source compound, an iron source compound and metallic titanium as raw materials, uniformly mixing, carrying out high-temperature melting in a smelting furnace, carrying out water quenching to obtain particles, grinding and dispersing the particles together with a carbon source compound to enable the particle size to reach a fineness index D90 of less than or equal to 0.2 mu m, carrying out spray drying to prepare powder, calcining in an atmosphere furnace at 600-800 ℃ for 40-300 minutes, and cooling to obtain the lithium iron phosphate anode material; the uniformity of the lithium iron phosphate anode material is improved by adopting a high-temperature melting method; introducing metal titanium powder to make Fe in molten liquid in high-temperature molten state3+Reduction to Fe2+And Ti produced4+Doping the lithium iron phosphate structure, and improving the electron conductivity of the lithium iron phosphate anode material by forming a vacancy; the specific surface area is reduced by grinding, dispersing and carbon coating, and the tap density of the lithium iron phosphate anode material is improved.
Description
Technical Field
The invention relates to the field of lithium ion batteries, in particular to a preparation method of a titanium-doped lithium iron phosphate anode material.
Background
The lithium iron phosphate positive electrode material has an olivine structure, can reversibly insert and remove lithium, has the advantages of high voltage, high specific capacity, good cycle performance, stable electrochemical performance, low price of raw materials, environmental friendliness and the like, and is considered to be one of the best positive electrode materials for preparing a lithium ion power battery or an energy storage battery with long service life, high power, high safety and low cost. However, the lithium iron phosphate positive electrode material has some inherent structural defects: the lithium ion migration rate, the electronic conductivity and the tap density of the material are all low.
At present, in order to improve the problem of poor conductivity of a synthetic material, a plurality of synthetic processes adopt a high-temperature solid-phase carbothermic method to prepare a lithium iron phosphate positive electrode material, and Fe203Preparing LiFeP0 by carbothermic method as raw material4a/C composite material. However, the particle size of the material prepared by the method is universalOn the micron level, the tap density of the material synthesized by the method is lower than that of the material synthesized by the traditional high-temperature solid phase method. In addition, in order to overcome the defects of the solid-phase sintering method, a new synthesis method, namely a liquid-phase method, appears, wherein all raw materials for synthesis are water-soluble and are carried out in a closed reaction kettle, so that molecular contact can be realized among the raw materials; the liquid phase method has the biggest advantages that ultrafine particles can be prepared, the tap density of the material can be improved because the product of the contact reaction between molecules can reach the nanometer level, but the equipment investment is large, the process is complex, the yield is relatively low, and the waste water treatment in the production process also needs complicated process and equipment.
Therefore, it is urgently needed to provide a preparation method of a lithium iron phosphate positive electrode material which has high conductivity, high tap density and simple process.
Disclosure of Invention
The invention aims to: the invention provides a preparation method of a titanium-doped lithium iron phosphate anode material, aiming at the problems of low specific capacitance and tap density of the lithium iron phosphate anode material caused by the phenomena of low conductivity, low tap density and complex preparation process flow of the lithium iron phosphate anode material.
The technical scheme adopted by the invention is as follows: a preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: according to n (Li): n (P): n (Fe): the atomic molar ratio of n (Ti) is 1.05:1: (1-x): x, respectively taking a lithium source compound, a phosphorus source compound, an iron source compound and metal titanium, wherein x is 0.05-0.15;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding a carbon source compound which is 0.1-0.15 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding a certain amount of purified water, putting into a ball milling tank for coarse grinding, and finally putting into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material to prepare a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material at the temperature of 600-800 ℃ under the protection of inert gas for 40-300 min, and cooling to obtain the finished lithium iron phosphate anode material.
Taking a lithium source compound, a phosphorus source compound, an iron source compound and metallic titanium as raw materials, uniformly mixing, then carrying out high-temperature melting in a smelting furnace, carrying out water quenching to obtain particles, and then grinding and dispersing the particles together with a carbon source compound to enable the particle size to reach the fineness index that D90 is less than or equal to 0.2 mu m; then, preparing powder by spray drying, calcining the powder in an atmosphere furnace at 600-800 ℃ for 40-300 minutes, and cooling to obtain a lithium iron phosphate anode material; the high-temperature melting method is adopted to mix the lithium source compound, the phosphorus source compound, the iron source compound and the metallic titanium in a liquid state, so that the uniformity of the components of the molten liquid is ensured, the reaction kinetic energy of the materials is increased, the molecular contact is realized, the rapid reaction of each raw material is promoted, and the reaction time is shortened; the purpose of introducing the metal titanium powder is to utilize the super-strong oxygen-depriving capability of the metal titanium at high temperature to lead Fe in the molten liquid3+Reduction to Fe2+And prevent Fe2+Oxidized again, thereby ensuring the olivine structure of the lithium iron phosphate anode material and the purity and consistency of the lithium iron phosphate anode material; on the other hand, Ti metal is oxidized to form Ti4+Ions are doped into the lithium iron phosphate structure, and the electron conductivity of the lithium iron phosphate anode material is improved by forming vacancies; the purpose of grinding and dispersing is to enable the particle size of the lithium iron phosphate pellets to reach the nanometer level that D90 is less than or equal to 0.2 mu m, reduce the specific surface area, improve the tap density of the lithium iron phosphate cathode material, and coat a layer of carbon film on the surface of the lithium iron phosphate pellets through calcination, so that the lithium iron phosphate pellets are in a spherical shape with uniform particles, further improve the tap density and improve the fluidity.
Preferably, the temperature of the furnace in the step (2) is controlled to be 1140-1200 ℃, and the atmosphere in the furnace is micro-oxidation, neutral or weak reduction. When high-temperature melting is adopted, in order to avoid erosion of the molten liquid to the inner wall of the melting furnace in the melting process, the uniformity of the components of the molten liquid is ensured, and in order to avoid the damage of the molten liquid structure caused by the melted-in impurities, the temperature of the melting furnace is controlled to be 1140-1200 ℃.
Preferably, the purified water is distilled water or deionized water, the oxygen content in the purified water is less than 9mg/L, and the mass of the purified water added in the step (4) is 1-3 times of the dry-based mass of the semi-finished lithium iron phosphate cathode material. Purified water is used for preventing impurities in water or oxygen dissolved in the water from polluting the lithium iron phosphate anode material; and (4) adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate cathode material in the step (4) to facilitate grinding and dispersion.
Preferably, the lithium source compound is at least one of lithium carbonate, lithium oxalate and lithium hydroxide.
Preferably, the phosphorus source compound is at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate and iron phosphate.
Preferably, the iron source compound is at least one of ferric oxide and ferric phosphate.
Preferably, the carbon source compound is at least one of glucose, sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber.
Preferably, the sand mill in the step (4) is a zirconia bead sand mill, the rotating speed is 1200-2600r/Min, and the sand milling time is 2-8 h. The lithium iron phosphate positive electrode material is sufficiently ground and dispersed so that the particle diameter D90 is 0.2 [ mu ] m or less.
Preferably, the air inlet temperature of the spray drying in the step (5) is 150-180 ℃, and the outlet temperature is 80-90 ℃. The grinded lithium iron phosphate anode material is fully dried, and the carbon coating on the surface of the next step is facilitated.
Further, the smelting furnace in the step (1) is a refractory material or a platinum-based lining high-temperature smelting furnace.
Further, the inert gas is any one of nitrogen, argon and hydrogen.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
1. according to the invention, a high-temperature melting method is adopted, so that the lithium source compound, the phosphorus source compound, the iron source compound and the metallic titanium are mixed in a liquid state, the uniformity of the components of the molten liquid is ensured, the reaction kinetic energy of the materials is increased, the molecular contact is realized, the rapid reaction of each raw material is promoted, and the reaction time is shortened;
2. by introducing the metal titanium powder, the invention utilizes the super-strong oxygen-depriving capability of the metal titanium at high temperature to lead the Fe in the molten liquid3+Reduction to Fe2+And prevent Fe2+Oxidized again, thereby ensuring the olivine structure of the anode material and the purity and consistency of the lithium iron phosphate anode material; on the other hand, Ti metal is oxidized to form Ti4+Ions are doped into the lithium iron phosphate structure, so that a vacancy is formed to improve the electron conductivity of the lithium iron phosphate anode material;
3. according to the invention, grinding and dispersing are adopted, so that the particle size of the lithium iron phosphate pellets reaches the nanometer level that D90 is less than or equal to 0.2 mu m, the specific surface area is reduced, the tap density of the lithium iron phosphate anode material is improved, and a layer of carbon film is coated on the surfaces of the lithium iron phosphate pellets through calcination, so that the lithium iron phosphate pellets are in a uniform-particle spherical shape, the tap density is further improved, and the fluidity is improved;
4. the preparation method disclosed by the invention is simple in process, low in energy consumption and production cost, and capable of carrying out industrial continuous large-scale stable production, and the produced lithium iron phosphate anode material has good electrochemistry, good material consistency and good processing performance.
5. The lithium iron phosphate anode material prepared by the method does not need to be broken and integrated, the original sphericity is kept, and the process flow is simplified.
Detailed Description
Example 1
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: taking 24.8g of lithium carbonate, 44.39g of ferric oxide, 73.93g of ammonium dihydrogen phosphate and 2.4g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.10 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material for 50min at the temperature of 700 ℃ under the protection of inert gas, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for charge and discharge tests, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge and discharge of 0.1C is 163.2mAh/g, the specific discharge capacity of the material under the charge and discharge multiplying power of 1C is 149mAh/g, and the tap density of the material is 1.62 g/mL.
Example 2
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: taking 24.8g of lithium carbonate, 43.42g of ferric oxide, 73.93g of ammonium dihydrogen phosphate and 3g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.11 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material at the temperature of 720 ℃ under the protection of inert gas for 70min, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for a charge-discharge test, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge-discharge of 0.1C is 161.2mAh/g, the specific discharge capacity of the material under the charge-discharge rate of 1C is 146mAh/g, and the tap density of the material is 1.61 g/mL.
Example 3
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: 24.8g of lithium carbonate, 41.39g of ferric oxide, 73.93g of ammonium dihydrogen phosphate and 4.2g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.12 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material for 90min at the temperature of 750 ℃ under the protection of inert gas, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for a charge-discharge test, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge-discharge of 0.1C is 161.8mAh/g, the specific discharge capacity of the material under the charge-discharge multiplying power of 1C is 148mAh/g, and the tap density of the material is 1.63 g/mL.
Example 4
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: 24.8g of lithium carbonate, 41.39g of ferric oxide, 73.93g of ammonium dihydrogen phosphate and 4.2g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.13 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material for 150min at the temperature of 800 ℃ under the protection of inert gas, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for charge and discharge tests, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge and discharge of 0.1C is 162.8mAh/g, the specific discharge capacity of the material under the charge and discharge multiplying power of 1C is 149mAh/g, and the tap density of the material is 1.63 g/mL.
Example 5
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: 34.2g of lithium oxalate, 43.4g of ferric oxide, 84.9g of diammonium hydrogen phosphate and 3g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.14 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material at the temperature of 780 ℃ under the protection of inert gas for 200min, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for a charge-discharge test, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge-discharge of 0.1C is 164.4mAh/g, the specific discharge capacity of the material under the charge-discharge multiplying power of 1C is 150mAh/g, and the tap density of the material is 1.64 g/mL.
Example 6
A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: 16.0g of lithium hydroxide, 78.0g of ferric phosphate, 14.5g of monoammonium phosphate and 4.2g of metal titanium powder;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water with the water temperature of 30 ℃, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding glucose which is 0.15 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding purified water which is 1-3 times of the dry basis weight of the semi-finished lithium iron phosphate anode material into a ball milling tank for coarse milling, and finally placing into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the ground semi-finished lithium iron phosphate cathode material at the inlet air temperature of 150-180 ℃ and the outlet air temperature of 80-90 ℃ to obtain a powdery semi-finished lithium iron phosphate cathode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material at the temperature of 800 ℃ under the protection of inert gas for 300min, and cooling to obtain the finished lithium iron phosphate anode material.
The carbon source compound glucose can be replaced by at least one of sucrose, polyethylene glycol, soluble starch, citric acid or methyl fiber with equal mass.
The obtained finished lithium iron phosphate anode material is assembled into a test battery for charge and discharge tests, the voltage of a test platform is 3.33-3.34V, the specific discharge capacity of the anode material under the charge and discharge of 0.1C is 163.8mAh/g, the specific discharge capacity of the material under the charge and discharge multiplying power of 1C is 149mAh/g, and the tap density of the material is 1.61 g/mL.
Table 1: specific discharge capacity and tap density of titanium-doped lithium iron phosphate positive electrode material under different charge-discharge rates (examples 1 to 3)
Table 2: specific discharge capacity and tap density of titanium-doped lithium iron phosphate positive electrode material at different charge and discharge rates (examples 4 to 6)
As can be seen from tables 1 and 2, the lithium iron phosphate cathode material doped with titanium prepared by the present invention has high specific discharge capacity and tap density.
The above-mentioned embodiments only express the specific embodiments of the present invention, and the description thereof is more specific and detailed, but the present invention should not be construed as being limited to the protection scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the invention, which falls within the scope of the invention.
Claims (9)
1. A preparation method of a titanium-doped lithium iron phosphate positive electrode material is characterized by comprising the following steps:
(1) taking raw materials: according to n (Li): n (P): n (Fe): the atomic molar ratio of n to Ti is 1.05:1 (1-x) x, wherein a lithium source compound, a phosphorus source compound, an iron source compound and metal titanium are respectively taken, and x is 0.05-0.15;
(2) heating and melting: uniformly mixing the raw materials, putting the mixture into a crucible, putting the crucible into a smelting furnace, and heating and melting the mixture at a certain temperature to a glass state;
(3) water quenching: adding the mixture melted to the glass state into purified water, performing water quenching, and filtering to obtain a semi-finished lithium iron phosphate anode material;
(4) grinding and dispersing: adding a carbon source compound which is 0.1-0.15 time of the dry basis weight of the semi-finished lithium iron phosphate anode material into the semi-finished lithium iron phosphate anode material, adding a certain amount of purified water, putting into a ball milling tank for coarse grinding, and finally putting into a sand mill for sand milling until the particle size D90 is below 0.2 mu m;
(5) and (3) drying: spray drying the product obtained in the step (4) to obtain a powdery semi-finished product lithium iron phosphate anode material;
(6) calcining and coating carbon; calcining the powdery semi-finished lithium iron phosphate anode material at the temperature of 600-800 ℃ under the protection of inert gas for 40-300 min, and cooling to obtain a finished lithium iron phosphate anode material;
the temperature of the smelting furnace in the step (2) is controlled to be 1140-1200 ℃, and the atmosphere in the smelting furnace is micro-oxidation, neutral or weak reducibility;
the purified water in the step (3) and the step (4) is distilled water or deionized water, and the oxygen content in the purified water is less than 9 mg/L.
2. The preparation method of the titanium-doped lithium iron phosphate positive electrode material according to claim 1, wherein the mass of the purified water added in the step (4) is 1-3 times of the dry basis mass of the semi-finished lithium iron phosphate positive electrode material.
3. The method according to claim 1, wherein the lithium source compound is at least one of lithium carbonate, lithium oxalate and lithium hydroxide.
4. The method for preparing the titanium-doped lithium iron phosphate positive electrode material according to claim 1, wherein the phosphorus source compound is at least one of ammonium dihydrogen phosphate, diammonium hydrogen phosphate and iron phosphate.
5. The method according to claim 1, wherein the iron source compound is at least one of ferric oxide and ferric phosphate.
6. The method for preparing the titanium-doped lithium iron phosphate positive electrode material according to claim 1, wherein the metal titanium is metal titanium powder.
7. The method for preparing the titanium-doped lithium iron phosphate positive electrode material according to claim 1, wherein the carbon source compound is at least one of glucose, sucrose, polyethylene glycol, soluble starch and citric acid.
8. The preparation method of the titanium-doped lithium iron phosphate cathode material according to claim 1, wherein the sand mill in the step (4) is a zirconia bead sand mill, the rotation speed is 1200-2600r/Min, and the sand milling time is 2-8 h.
9. The preparation method of the titanium-doped lithium iron phosphate cathode material as claimed in claim 1, wherein the inlet temperature of the spray drying in the step (5) is 150-180 ℃ and the outlet temperature is 80-90 ℃.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101200289A (en) * | 2006-12-15 | 2008-06-18 | 中国电子科技集团公司第十八研究所 | Lithium ferric phosphate material and method for making same |
| CN102013489A (en) * | 2010-10-28 | 2011-04-13 | 河北工业大学 | Metallic titanium doped carbon-coating lithium iron phosphate and preparation method thereof |
| CN104241607A (en) * | 2014-10-10 | 2014-12-24 | 威远县大禾陶瓷原料有限公司 | Preparation method of LFP (lithium ferric phosphate) electrode material |
| CN105514427A (en) * | 2015-12-23 | 2016-04-20 | 邬石根 | Ti doped LiFe(1-x)TixPO4 electrode material |
-
2017
- 2017-10-18 CN CN201710971049.5A patent/CN107611413B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101200289A (en) * | 2006-12-15 | 2008-06-18 | 中国电子科技集团公司第十八研究所 | Lithium ferric phosphate material and method for making same |
| CN102013489A (en) * | 2010-10-28 | 2011-04-13 | 河北工业大学 | Metallic titanium doped carbon-coating lithium iron phosphate and preparation method thereof |
| CN104241607A (en) * | 2014-10-10 | 2014-12-24 | 威远县大禾陶瓷原料有限公司 | Preparation method of LFP (lithium ferric phosphate) electrode material |
| CN105514427A (en) * | 2015-12-23 | 2016-04-20 | 邬石根 | Ti doped LiFe(1-x)TixPO4 electrode material |
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