CN111682202B - Method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) -assisted two-fluid spraying solid phase - Google Patents
Method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) -assisted two-fluid spraying solid phase Download PDFInfo
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Abstract
The invention provides a method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) assisted two-fluid spraying solid phase, which adopts PVA as an additive, forms a rodlike framework by controlling the surface tension, solid content and viscosity of slurry, forms a stable nanometer rodlike framework structure by controlling the inlet and outlet air temperature, compressed gas pressure and feed flow of two-fluid spraying, and finally prepares the nanometer rodlike structure lithium iron phosphate by high-temperature sintering and crushing in inert atmosphere; the lithium iron phosphate with the rod-like structure prepared by the invention has the technical effects of high battery capacity and excellent low-temperature performance, and is greatly superior to the lithium iron phosphate prepared by the prior art.
Description
Technical Field
The invention relates to the field of new energy materials, in particular to a method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) assisted two-fluid spraying solid phase synthesis.
Background
The lithium iron phosphate as the anode material of the lithium ion battery has the characteristics of long cycle life, low self-discharge rate, wide working temperature range, no memory effect, environmental friendliness and the like, so that the lithium iron phosphate is widely applied to the fields of portable electronic products, electric vehicles, aviation, aerospace, national defense, energy storage and the like.
Because the lithium iron phosphate has slow lithium ion transmission rate and poor electronic conductivity, the exertion of the electrical property of the lithium iron phosphate is severely limited, particularly gram capacity and low temperature property. The problem of poor electronic conductivity is mainly solved by carbon coating in the industrial production process, and the carbon coating can improve the conductivity among particles and inhibit the growth of the particles. The lithium iron phosphate only has a one-dimensional lithium ion transmission channel, and the problem of the lithium ion transmission rate is mainly solved by adopting a particle nano technology, so that the synthesis of a structure with nano scale and favorable for the lithium ion one-dimensional channel transmission becomes an effective way for solving the problem of the slow lithium ion diffusion rate. Common one-dimensional nanostructures mainly comprise nanotubes, nanowires, nanorods and nanobelts, and the one-dimensional nanostructures are generally synthesized by a hydrothermal method. As is well known, the hydrothermal method requires high-temperature high-pressure reaction, and then washing and filtering, and has the disadvantages of complex production process, high risk coefficient, strict equipment requirements and difficult industrial popularization. In view of the above, a simple solid-phase synthesis method of nanorod-shaped lithium iron phosphate is proposed.
Disclosure of Invention
The invention aims to provide a method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) -assisted two-fluid spraying solid-phase synthesis, which has the advantages of simple production process, high safety factor and suitability for large-scale industrial production, and the prepared material battery has high capacity and excellent low-temperature performance.
The invention aims to realize the technical scheme that a method for synthesizing rodlike lithium iron phosphate by PVA-assisted two-fluid spraying solid phase comprises the following steps:
s1, preparing rod-shaped lithium iron phosphate slurry: uniformly mixing a lithium source, an iron source, a phosphorus source, a carbon source and an additive PVA to obtain a rod-like lithium iron phosphate slurry;
s2, preparing a rod-shaped lithium iron phosphate precursor: carrying out two-fluid spray drying on the rod-shaped lithium iron phosphate slurry prepared in the step S1 to obtain a rod-shaped lithium iron phosphate precursor;
s3, preparing the rod-shaped lithium iron phosphate: sintering the rod-shaped lithium iron phosphate precursor prepared in the step S2 in a high-purity inert atmosphere, heating to 600-800 ℃ at a speed of 2.5-5 ℃/min, preserving heat for 6-12 h, and then naturally cooling to below 100 ℃; and (3) crushing by using a jet mill, wherein the air pressure of 0.6MPa is adopted for the jet crushing to obtain the rod-shaped lithium iron phosphate with the diameter of 30-80 nm and the length of 100-600 nm.
Further, the addition amounts of the lithium source, the iron source and the phosphorus source in the step S1 are Li: fe: the molar ratio of P is (1.0-1.1): 1: (1.0-1.1); the adding amount of the carbon source is 1-10% of the mass of the finished product lithium iron phosphate; the additive PVA accounts for 2 to 15 percent of the total mass of the mixed raw materials; the solvent of the rodlike lithium iron phosphate slurry is water or ethanol.
Further, the viscosity of the rod-like lithium iron phosphate slurry prepared in the step S1 is 500-2500 mPa & S, the surface tension is less than or equal to 0.04N/m, and the solid content is 20-30%.
Further, the air inlet temperature of the two-fluid spraying adopted in the step S2 is 280-380 ℃; the air outlet temperature is 85-105 ℃; the diameter of the nozzle is 0.1-2 mm; the air source is compressed air, and the air is preheated at 150-250 ℃ and the pressure is 0.3-0.8 MPa before entering the spray gun; the spraying feed flow is 500-1500L/h.
Further, in the step S1, the lithium source is one or more of lithium hydroxide, lithium carbonate, and lithium dihydrogen phosphate; the iron source is one or more of ferrous oxalate, ferric phosphate, ferric oxide, iron powder, ferroferric oxide and ferric nitrate; the phosphorus source is one or more of diammonium phosphate, monoammonium phosphate, phosphoric acid and iron phosphate.
Further, in the step S1, the carbon source in the step S1 is one or more of glucose, sucrose, citric acid, oxalic acid, polypropylene, polyethylene, graphene, acetylene black, and PVA.
Further, the inert atmosphere adopted in step S3 is one or more of nitrogen, argon and helium.
Further, the amount of PVA used in step S1 is 6% of the total mass of the raw materials for mixing.
Further, the viscosity of the rod-like lithium iron phosphate slurry prepared in the step S1 is 1500mPa · S.
Further, the feeding speed of the two-fluid spray in the step S2 is 1200L/h, the air inlet and outlet temperatures are 300 ℃ and 95 ℃ respectively, and the air inlet pressure is 0.5MPa.
The invention provides a method for synthesizing rodlike lithium iron phosphate by PVA (polyvinyl alcohol) assisted two-fluid spraying solid phase, which adopts PVA as an additive, forms a rodlike framework by controlling the surface tension, solid content and viscosity of slurry, forms a stable nanometer rodlike framework structure by controlling the inlet and outlet air temperature, compressed gas pressure and feeding flow of two-fluid spraying, and finally prepares the nanometer rodlike structure lithium iron phosphate by high-temperature sintering and crushing in inert atmosphere. The nano-rod-shaped lithium iron phosphate shortens the transmission distance of lithium ions, solves the problem that the lithium ion deintercalation channel is easy to block due to only one-dimensional channel of the lithium ions in the charging and discharging process of the lithium iron phosphate, further influences the transmission rate of the lithium ions, enables the deintercalation of the lithium ions to be smooth and unimpeded, and improves the electrical performance of the lithium iron phosphate.
PVA can reduce the surface tension of the precursor slurry. The precursor slurry solution can overcome the acting force of shearing and stretching under the action of large surface tension, has strong tendency of self-shrinking into liquid drops, and can form more particles at the moment. When the surface tension is sufficiently small, a large number of rod-like structures are formed when analyzed according to the rod-forming principle. PVA can change the physical property of the slurry, greatly reduce the surface tension of the slurry and is beneficial to the formation of a rod-shaped structure. Secondly, PVA may form a rod-like framework with the raw materials when preparing the slurry. The mixed slurry must be combined with a certain amount of PVA when forming a rod-shaped skeleton. If the content of the raw materials is too much, the acting force between crystal grains is too weak, and enough PVA does not participate in forming a rod-shaped framework; if the content of the raw material is too small, the solid content in the rod-like skeleton is too low, and the rod-like skeleton formed before the decomposition of PVA by calcination at a later stage is also broken. Therefore, a proper amount of PVA can form a rod-shaped framework structure with the raw materials. Again, PVA may provide a carbon source. PVA can provide partial carbon source in the sintering process of lithium iron phosphate and inhibit the growth of crystal grains in the sintering process of lithium iron phosphate. The amount of PVA used is preferably 6% by mass of the total amount of the raw materials to be mixed.
Viscosity requirements for two-fluid sprays. The viscosity of the rod-like lithium iron phosphate slurry prepared in the step S1 mainly influences the process from the step S1 of compressing the slurry from the reaction kettle to the nozzle and then drying the slurry after spraying. When the viscosity is too low, the disturbance wave formed in the spraying process is too large, so that the rod-shaped framework is damaged or can not be formed any more, and when the flow rate of the fluid in the nozzle is constant, the fluid in the nozzle can be ensured to be laminar flow or the turbulence degree is smaller, so that when the slurry leaves the nozzle, the slurry is formed into a rod shape under the action of tensile shearing force. And the greater the viscosity, the greater the cohesive energy in the slurry, at which point the formation of particles can be greatly reduced, thereby forming a rod-like structure. Thus, a rod-like structure can be formed with an appropriate viscosity. The viscosity of the rod-like lithium iron phosphate slurry prepared in step S1 is preferably 1500mPa · S.
Two-fluid spray requirements for feed rate. The feeding amount influences the gas-liquid momentum ratio, when the feeding amount is large, the gas-liquid momentum ratio is reduced, enough shearing force can be formed at the moment, the bar-shaped structure is favorably formed, but when the feeding amount is too large, the slurry at the nozzle is easy to form violent turbulence, and the bar-shaped structure is not easy to form at the moment. The preferred feed rate is 1200L/h.
The two-fluid spraying has requirements on the temperature and pressure of inlet and outlet air. The evaporation speed of the liquid drops is influenced by the temperature of the inlet air and the pressure of the inlet air, if the evaporation speed of the liquid drops is too high, the rod-shaped structure is easy to form a hollow structure, and the hollow structure can greatly reduce the tap density of the finished lithium iron phosphate product and the compaction density of the pole piece. Therefore, the preferred air inlet and outlet temperatures are 300 ℃ and 95 ℃ respectively, and the air inlet pressure is 0.5MPa.
The lithium iron phosphate with the rod-like structure prepared by the invention has the technical effects of high battery capacity and excellent low-temperature performance, and is greatly superior to the lithium iron phosphate prepared by the prior art.
Drawings
FIG. 1 is a flow chart of the experiment of the present invention.
FIG. 2 is a scanning electron micrograph of example 1 of the present invention
FIG. 3 is a scanning electron micrograph of example 2 of the present invention
FIG. 4 is a scanning electron micrograph of example 3 of the present invention
FIG. 5 is a scanning electron micrograph of example 4 of the present invention
FIG. 6 is a scanning electron micrograph of example 5 of the present invention
FIG. 7 is a scanning electron micrograph of example 6 of the present invention
FIG. 8 is a scanning electron micrograph of example 7 of the present invention
FIG. 9 is a scanning electron micrograph of example 8 of the present invention
FIG. 10 is a scanning electron micrograph of example 9 of the present invention
FIG. 11 is a scanning electron micrograph of example 10 of the present invention
FIG. 12 is a scanning electron micrograph of example 11 of the present invention
FIG. 13 is a scanning electron micrograph of example 12 of the present invention
FIG. 14 is a scanning electron micrograph of example 13 of the present invention
FIG. 15 is a scanning electron micrograph of example 14 of the present invention
FIG. 16 is a scanning electron micrograph of example 15 of the present invention
FIG. 17 is a scanning electron micrograph of example 16 of the present invention
FIG. 18 is a scanning electron micrograph of example 17 of the present invention
FIG. 19 is a scanning electron micrograph of example 18 of the present invention
FIG. 20 is a scanning electron micrograph of example 19 of the present invention
FIG. 21 is a scanning electron micrograph of example 20 of the present invention
FIG. 22 is a graph showing comparison of room temperature 1C discharge in examples 1 and 11 of the present invention
FIG. 23 is a graph showing comparison of room temperature 1C discharge in example 2 and example 12 of the present invention
FIG. 24 is a graph showing comparison of room temperature 1C discharge in examples 3 and 13 of the present invention
FIG. 25 is a graph showing comparison of room temperature 1C discharge in examples 4 and 14 of the present invention
FIG. 26 is a graph showing comparison of room temperature 1C discharges in examples 5 and 15 of the present invention
FIG. 27 is a graph showing comparison of room temperature 1C discharges in examples 6 and 16 of the present invention
FIG. 28 is a graph showing comparison of room temperature 1C discharges in examples 7 and 17 of the present invention
FIG. 29 is a graph showing comparison of room temperature 1C discharge in examples 8 and 18 of the present invention
FIG. 30 is a graph showing comparison of room-temperature 1C discharges in examples 9 and 19 of the present invention
FIG. 31 is a graph showing comparison of room temperature 1C discharge in examples 10 and 20 of the present invention
Detailed Description
The present invention will be further described with reference to the following examples.
Example 1
443g of LiOH & H are slowly added in sequence 2 O、815g Fe 2 O 3 、1162g NH 4 H 2 PO 4 64.7g of glucose monohydrate and 158g of PVA were added to 10.6L of water, and after each addition the next material was added and stirred for 0.5hAnd stirring for 1h after the addition is finished to obtain the uniformly mixed rod-like lithium iron phosphate slurry S1. The surface tension of the tested slurry is 0.01N/m, the viscosity is 1500 mPa.s, the solid content is 25%, PVA accounts for 6% of the total weight of the added raw materials, and the ratio of Li: fe: the molar ratio of P is 1.05:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 0.1mm, preheated compressed air is 200 ℃, the pressure is 0.5MPa, the air inlet temperature is 300 ℃, the air outlet temperature is 95 ℃ and the feeding flow is 1200L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity nitrogen atmosphere, namely heating to 720 ℃ at a speed of 3.2 ℃/min, preserving heat for 8h, and then naturally cooling to 85 ℃; and (3) crushing by using an airflow crusher, wherein the airflow crushing adopts the air pressure of 0.6MPa to obtain the rod-shaped lithium iron phosphate. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 5.4 percent, the discharge gram capacity of 155mAh/g and the low-temperature discharge retention rate of 98.5 percent at-20 ℃.
Example 2
426g of LiOH & H are slowly added in sequence 2 O、564g Fe、1162g NH 4 H 2 PO 4 Adding 7.4g of sucrose and 215g of PVA into 8.5L of water, adding each substance, stirring for 0.5h, adding the next substance, and stirring for 1h after all the substances are added to obtain uniformly mixed rod-shaped lithium iron phosphate slurry S1. The surface tension of the test slurry was 0.008N/m, the viscosity was 1678mPa · s, the solid content was 28%, PVA accounted for 9.1% of the total weight of the added raw materials, li: fe: the molar ratio of P is 1.01:1:1.
and (3) carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 0.15mm, preheated compressed air is 220 ℃, the pressure is 0.6MPa, the air inlet temperature is 300 ℃, the air outlet temperature is 100 ℃ and the feeding flow is 1000L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity nitrogen atmosphere, namely heating to 690 ℃ at a speed of 4 ℃/min, preserving heat for 10h, and then naturally cooling to 73 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 6.2 percent, the discharge gram capacity of 152mAh/g and the low-temperature discharge retention rate of 95.4 percent at-20 ℃.
Example 3
434g of LiOH H are added in sequence slowly 2 O, 1468g of ferrous oxalate, 1162gNH 4 H 2 PO 4 Adding 11.8g of polypropylene and 67g of PVA into 13.1L of ethanol, stirring each substance for 0.5h after adding, then adding the next substance, and stirring all the substances for 1h after adding to obtain uniformly mixed rod-like lithium iron phosphate slurry S1. The surface tension of the test slurry was 0.03N/m, the viscosity was 1100 mPas, the solid content was 24%, PVA was 2.1% by weight of the total amount of the raw materials added, and Li: fe: the molar ratio of P is 1.03:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 0.12mm, preheated compressed air is 180 ℃, the pressure is 0.45MPa, the air inlet temperature is 350 ℃, the air outlet temperature is 95 ℃ and the feeding flow is 1300L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity nitrogen atmosphere, namely heating to 780 ℃ at a speed of 3 ℃/min, preserving heat for 6h, and then naturally cooling to 67 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 1.2 percent, the discharge gram capacity of 153mAh/g and the low-temperature discharge retention rate of 98.2 percent at-20 ℃.
Example 4
422g of LiOH & H are slowly added in sequence 2 O、1523g FePO 4 3.1g of polyethylene and 292g of PVA are added into 10.2L of water, each substance is added and then stirred for 0.5h, then the next substance is added, and all the substances are stirred for 1h after being added, so that the uniformly mixed rod-shaped lithium iron phosphate slurry S1 is obtained. The surface tension of the tested slurry is 0.002N/m, the viscosity is 800 mPa.s, the solid content is 22%, PVA accounts for 15% of the total weight of the added raw materials, and Li: fe: the molar ratio of P is 1:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 0.1mm, preheated compressed air is 220 ℃, the pressure is 0.7MPa, the air inlet temperature is 380 ℃, the air outlet temperature is 90 ℃ and the feeding flow is 1500L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity helium atmosphere, namely heating to 750 ℃ at a speed of 5 ℃/min, preserving heat for 8h, and then naturally cooling to 55 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 9.0 percent and the discharge gram capacity of 150mAh/g, and the low-temperature discharge retention rate of-20 ℃ is 94.5 percent.
Example 5
426g of LiOH & H are slowly added in sequence 2 O, 564g Fe, 1153g H of 85% concentration 3 PO 4 3.8g of graphene and 86g of PVA are added into 8.0L of ethanol, each substance is added and then stirred for 0.5h, then the next substance is added, and all the substances are stirred for 1h after being added, so that the uniformly mixed rod-shaped lithium iron phosphate slurry S1 is obtained. The surface tension of the tested slurry is 0.038N/m, the viscosity is 2212mPa & s, the solid content is 28%, PVA accounts for 3.85% of the total weight of the added raw materials, and the ratio of Li: fe: the molar ratio of P is 1.01:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 1.5mm, the temperature of preheated compressed air is 250 ℃, the pressure is 0.8MPa, the air inlet temperature is 380 ℃, the air outlet temperature is 100 ℃ and the feeding flow is 1450L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 720 ℃ at a speed of 4.5 ℃/min, preserving heat for 12 hours, and then naturally cooling to 82 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 1.5 percent and the discharge gram capacity of 155mAh/g, and the low-temperature discharge retention rate of-20 ℃ is 96.8 percent.
Example 6
371g of Li were slowly charged in sequence 2 CO 3 、1523g FePO 4 Adding 38g of acetylene black and 95g of PVA into 10.1L of water, adding each substance, stirring for 0.5h, adding the next substance, and stirring for 1h after all the substances are added to obtain uniformly mixed rod-shaped lithium iron phosphate slurry S1. The surface tension of the test slurry was 0.02N/m, the viscosity was 500 mPas, the solid content was 20%, PVA accounted for 4.7% of the total weight of the added raw materials, li: fe: the molar ratio of P is 1:1:1.
and (3) carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 1.8mm, the temperature of preheated compressed air is 250 ℃, the pressure is 0.8MPa, the air inlet temperature is 380 ℃, the air outlet temperature is 105 ℃ and the feeding flow is 1000L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 800 ℃ at a speed of 4 ℃/min, preserving heat for 10h, and then naturally cooling to 95 ℃; crushing by using a jet mill, wherein the air pressure of the jet mill is 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 4.0 percent, the discharge gram capacity of 154mAh/g and the low-temperature discharge retention rate of 92.7 percent at-20 ℃.
Example 7
In turn, 408g of Li were slowly charged 2 CO 3 、2443g Fe(NO 3 ) 3 、1467g(NH 4 ) 2 HPO 4 86.5g of citric acid and 91g of PVA are added into 15L of water, each substance is added and then stirred for 0.5h, the next substance is added, and all the substances are stirred for 1h after being added, so that uniformly mixed rod-shaped lithium iron phosphate slurry S1 is obtained. The surface tension of the tested slurry is 0.04N/m, the viscosity is 2500 mPa.s, the solid content is 30%, PVA accounts for 2% of the total weight of the added raw materials, and Li: fe: the molar ratio of P is 1.1:1:1.1.
and (3) carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 2.0mm, preheated compressed air is 180 ℃, the pressure is 0.3MPa, the air inlet temperature is 280 ℃, the air outlet temperature is 85 ℃ and the feeding flow is 500L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 600 ℃ at a speed of 2.5 ℃/min, preserving heat for 10h, and then naturally cooling to 100 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 3.5 percent, the discharge gram capacity of 153mAh/g and the low-temperature discharge retention rate of 93.5 percent at-20 ℃.
Example 8
1050g of LiH are slowly added in turn 2 PO 4 1468g of ferrous oxalate, 13.7g of oxalic acid and 60g of PVA are added into 9.7L of water, each substance is added and stirred for 0.5h, then the next substance is added, and all the substances are stirred for 1h after being added, so that the rod-shaped lithium iron phosphate slurry S1 which is uniformly mixed is obtained. The surface tension of the test slurry was 0.037N/m, the viscosity was 783mPa · s, the solid content was 26%, PVA accounted for 2.3% of the total weight of the raw materials added, li: fe: the molar ratio of P is 1:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 1.8mm, preheated compressed air is 200 ℃, the pressure is 0.6MPa, the air inlet temperature is 330 ℃, the air outlet temperature is 95 ℃ and the feeding flow is 1400L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 700 ℃ at a speed of 3.5 ℃/min, preserving heat for 8h, and then naturally cooling to 72 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 11.8 percent, the discharge gram capacity of 152mAh/g and the discharge retention rate of 94.1 percent at the low temperature of-20 ℃.
Example 9
1050g of LiH are slowly added in turn 2 PO 4 、815g Fe 2 O 3 And adding 261g of PVA into 9.2L of water, stirring each substance for 0.5h after adding, then adding the next substance, and stirring all the substances for 1h after adding to obtain the uniformly mixed rod-like lithium iron phosphate slurry S1. The surface tension of the test slurry is 0.003N/m, the viscosity is 960 mPa.s, the solid content is 23%, PVA accounts for 12.2% of the total weight of the added raw materials, and the ratio of Li: fe: the molar ratio of P is 1:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 1.8mm, preheated compressed air is 180 ℃, the pressure is 0.6MPa, the air inlet temperature is 320 ℃, the air outlet temperature is 105 ℃ and the feeding flow is 800L/h to prepare a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 760 ℃ at a speed of 5 ℃/min, preserving heat for 8h, and then naturally cooling to 68 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 2.0 percent, the discharge gram capacity of 150mAh/g and the low-temperature discharge retention rate of 90.8 percent at-20 ℃.
Example 10
1050g of LiH are slowly added in turn 2 PO 4 564g of Fe and 194g of PVA are added into 8.6L of water, each substance is added and then stirred for 0.5h, the next substance is added, all the substances are stirred for 1h after being added, and the uniformly mixed rod-shaped lithium iron phosphate slurry S1 is obtained. Test slurrySurface tension of 0.008N/m, viscosity of 590mPa · s, solid content of 21%, PVA accounting for 10.3% of the total weight of the added raw materials, li: fe: the molar ratio of P is 1:1:1.
and carrying out two-fluid spraying on the S1 under the conditions that the diameter of a nozzle is 0.6mm, preheated compressed air is 220 ℃, the pressure is 0.55MPa, the air inlet temperature is 350 ℃, the air outlet temperature is 105 ℃ and the feeding flow is 1350L/h to obtain a rod-shaped lithium iron phosphate precursor S2.
Sintering the S2 in a high-purity argon atmosphere, namely heating to 680 ℃ at a speed of 5 ℃/min, preserving heat for 12h, and then naturally cooling to 89 ℃; pulverizing with jet mill under 0.6 MPa. The rod-shaped lithium iron phosphate prepared by the embodiment has the diameter of 30-80 nm, the length of 100-600 nm, the carbon content of 5.2 percent, the discharge gram capacity of 151mAh/g and the discharge retention rate of 92.7 percent at the low temperature of-20 ℃.
Example 11
Example 11 is a comparative example of example 1, and lithium iron phosphate was prepared under the same conditions as in example 1 by using glucose as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are hollow spheres with the diameter of 20-60 mu m, the carbon content is 5.3%, the discharge gram capacity is 135mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 72.6%.
Example 12
Example 12 is a comparative example of example 2, and lithium iron phosphate was prepared under the same conditions as in example 2 by using sucrose as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate prepared by the embodiment is in a sphere-like shape with the primary particle diameter of about 500nm, the carbon content is 6.1 percent, the discharge capacity is 132mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 73.5 percent.
Example 13
Example 13 is a comparative example of example 3, and lithium iron phosphate was prepared under the same conditions as in example 3 by using polypropylene as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are spherical with the diameter of about 10 mu m, the carbon content is 1.4 percent, the discharge gram capacity is 136mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 80.3 percent.
Example 14
Example 14 is a comparative example of example 4, and lithium iron phosphate was prepared under the same conditions as in example 4 by using polyethylene as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are hollow spheres with the diameter of about 20-60 mu m, the carbon content is 8.8%, the gram-discharge capacity is 137mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 83.8%.
Example 15
Example 15 is a comparative example of example 5, and lithium iron phosphate was prepared by using graphene as a carbon source instead of PVA and performing spraying using centrifugal spray drying instead of two-fluid spraying under the same conditions as in example 5. The lithium iron phosphate secondary particles prepared by the embodiment are solid spheres with the diameter of about 20 mu m, the carbon content is 1.6 percent, the discharge gram capacity is 134mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 76.4 percent.
Example 16
Example 16 is a comparative example of example 6, and lithium iron phosphate was prepared under the same conditions as in example 6 by using acetylene black as a carbon source instead of PVA and by spraying with centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are hollow spheres with the diameter of about 10 mu m, the carbon content is 4.2 percent, the discharge gram capacity is 133mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 84.2 percent.
Example 17
Example 17 is a comparative example to example 7, and lithium iron phosphate was prepared under the same conditions as in example 7 by using citric acid as a carbon source instead of PVA and performing spraying by centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are solid spheres with the diameter of about 20-60 mu m, the carbon content is 3.3%, the discharge gram capacity is 131mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 82.1%.
Example 18
Example 18 is a comparative example of example 8, and lithium iron phosphate was prepared under the same conditions as in example 8 by using oxalic acid as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are hollow spheres with the diameter of about 20-60 mu m, the carbon content is 11.6%, the gram-discharge capacity is 138mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 78.4%.
Example 19
Example 19 is a comparative example to example 9, and lithium iron phosphate was prepared under the same conditions as in example 9 by using glucose as a carbon source instead of PVA and by spraying using centrifugal spray drying instead of two-fluid spraying. The lithium iron phosphate secondary particles prepared by the embodiment are solid spheres with the diameter of about 30 mu m, the carbon content is 2.2 percent, the discharge gram capacity is 134mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 72.3 percent.
Example 20
Example 20 is a comparative example of example 20, and lithium iron phosphate was prepared under the same conditions as in example 20, using glucose as a carbon source instead of PVA, and using centrifugal spray drying instead of two-fluid spraying for spraying. The lithium iron phosphate primary particles prepared by the embodiment are spherical with the diameter of about 300nm, the carbon content is 5.1 percent, the discharge gram capacity is 132mAh/g, and the low-temperature discharge retention rate at-20 ℃ is 75.6 percent.
From the materials synthesized in fig. 2-11, i.e., the examples, it can be seen that we successfully prepared rod-like lithium iron phosphate, which has a diameter of 30-80 nm, a length of 100-600 nm, a uniform structure, and voids left between particles, thereby facilitating the infiltration of the electrolyte; FIGS. 12-21, which are comparative example synthesized, show that the material structure is a hollow or solid sphere, and the spheres have a large and non-uniform particle size distribution; it can be seen in fig. 22-31 that the gram capacity of discharge in the examples is significantly higher than the comparative examples and the discharge plateau is higher. From the above pictures, we can see that we successfully prepare the rod-like lithium iron phosphate material with excellent performance.
Uniformly mixing the lithium iron phosphate prepared in the examples 1 to 20, PVDF, SP and S-0 according to a mass ratio of 96.5.
The following table shows the results of testing lithium iron phosphate prepared in examples 1 to 20:
according to the detection results, the rod-shaped lithium iron phosphate synthesized by the PVA-assisted two-fluid spray solid phase method has the advantages of high gram capacity and good low-temperature performance.
It should be understood that the examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that any changes and modifications to the present invention may occur to those skilled in the art after reading the present teachings, and such equivalents are also intended to be limited by the appended claims.
Claims (7)
1. A method for synthesizing rodlike lithium iron phosphate by PVA-assisted two-fluid spraying solid phase is characterized by comprising the following steps:
s1, preparing rod-shaped lithium iron phosphate slurry: uniformly mixing a lithium source, an iron source, a phosphorus source, a carbon source and an additive PVA (polyvinyl alcohol) to obtain rod-shaped lithium iron phosphate slurry;
s2, preparing a rod-shaped lithium iron phosphate precursor: carrying out two-fluid spray drying on the rod-shaped lithium iron phosphate slurry prepared in the step S1 to obtain a rod-shaped lithium iron phosphate precursor;
s3, preparing the rod-shaped lithium iron phosphate: sintering the rod-shaped lithium iron phosphate precursor prepared in the step S2 in a high-purity inert atmosphere, heating to 600-800 ℃ at a speed of 2.5-5 ℃/min, preserving heat for 6-12 h, and then naturally cooling to below 100 ℃; crushing by using a jet mill, wherein the air pressure of 0.6MPa is adopted for the jet crushing to obtain rod-shaped lithium iron phosphate with the diameter of 30-80 nm and the length of 100-600 nm;
in the step S1, the addition amounts of the lithium source, the iron source and the phosphorus source are Li: fe: the molar ratio of P is (1.0-1.1): 1: (1.0-1.1); the adding amount of the carbon source is 1-10% of the mass of the finished product lithium iron phosphate; the additive PVA accounts for 2 to 15 percent of the total mass of the mixed raw materials; the solvent of the rod-like lithium iron phosphate slurry is water or ethanol;
the viscosity of the rod-like lithium iron phosphate slurry prepared in the step S1 is 500-2500 mPa & S, the surface tension is less than or equal to 0.04N/m, and the solid content is 20-30%;
the inlet air temperature of the two-fluid spraying adopted in the step S2 is 280-380 ℃; the air outlet temperature is 85-105 ℃; the diameter of the nozzle is 0.1-2 mm; the air source is compressed air, and the air is preheated at 150-250 ℃ and the pressure is 0.3-0.8 MPa before entering the spray gun; the spraying feeding flow rate is 500-1500L/h.
2. The method for solid-phase synthesis of rodlike lithium iron phosphate by PVA-assisted two-fluid spraying according to claim 1, wherein the lithium source in step S1 is one or more of lithium hydroxide, lithium carbonate and lithium dihydrogen phosphate; the iron source is one or more of ferrous oxalate, ferric phosphate, ferric oxide, iron powder, ferroferric oxide and ferric nitrate; the phosphorus source is one or more of diammonium phosphate, monoammonium phosphate, phosphoric acid and ferric phosphate.
3. The method for solid-phase synthesis of rodlike lithium iron phosphate through PVA-assisted two-fluid spraying according to claim 1, wherein the carbon source in the step S1 is one or more of glucose, sucrose, citric acid, oxalic acid, polypropylene, polyethylene, graphene, acetylene black and PVA.
4. The method for solid-phase synthesis of rodlike lithium iron phosphate by PVA-assisted two-fluid spraying according to claim 1, wherein the inert atmosphere adopted in step S3 is one or more of nitrogen, argon and helium.
5. The method for solid-phase synthesis of rod-like lithium iron phosphate by PVA (polyvinyl alcohol) assisted two-fluid spraying according to any one of claims 1 to 4, wherein the amount of PVA used in the step S1 is 6% of the total mass of the mixed raw materials.
6. The method for solid-phase synthesis of rodlike lithium iron phosphate by PVA (polyvinyl alcohol) auxiliary two-fluid spraying according to any one of claims 1 to 4, wherein the viscosity of the rodlike lithium iron phosphate slurry prepared in the step S1 is 1500 mPa-S.
7. The method for solid-phase synthesis of rodlike lithium iron phosphate by PVA (polyvinyl alcohol) assisted two-fluid spraying according to any one of claims 1 to 4, wherein the feeding speed of the two-fluid spraying in the step S2 is 1200L/h, the air inlet and outlet temperatures are 300 ℃ and 95 ℃ respectively, and the air inlet pressure is 0.5MPa.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102208627A (en) * | 2011-05-11 | 2011-10-05 | 华南理工大学 | Method for preparing LiFePO4/C composite anode material by spray drying |
| CN102593451A (en) * | 2012-03-12 | 2012-07-18 | 中国科学院过程工程研究所 | Lithium manganese phosphate nanofiber as anode material of lithium ion battery and preparation method of lithium manganese phosphate nanofiber |
| CN102945962A (en) * | 2012-12-07 | 2013-02-27 | 山东铂源锂电科技有限公司 | Nanorod-shaped lithium iron phosphate material and preparation method thereof |
| CN103996846A (en) * | 2014-04-14 | 2014-08-20 | 江苏中欧材料研究院有限公司 | Preparation method for lithium iron phosphate positive electrode material with controllable particle size |
| CN104300119A (en) * | 2013-07-17 | 2015-01-21 | 东莞市长安东阳光铝业研发有限公司 | Preparation method for lithium iron phosphate cathode material |
| CN104701536A (en) * | 2013-12-09 | 2015-06-10 | 青岛平度市旧店金矿 | Process for preparing high-performance lithium battery positive electrode material through spray drying method |
| CN104752692A (en) * | 2013-12-30 | 2015-07-01 | 北京有色金属研究总院 | Preparation method for LiFePO4/C composite anode material |
| WO2016141706A1 (en) * | 2015-03-10 | 2016-09-15 | 中国科学院过程工程研究所 | Composite-coated lithium iron phosphate and preparation method therefor, and lithium ion battery |
| CN106229505A (en) * | 2016-08-17 | 2016-12-14 | 深圳市贝特瑞纳米科技有限公司 | A kind of high-density spherical nano lithium iron phosphate material and preparation method thereof and the lithium ion battery comprising it |
| CN107394152A (en) * | 2017-07-17 | 2017-11-24 | 深圳市贝特瑞纳米科技有限公司 | The spherical composite of the high graphene-based LiFePO4 of conductance, its preparation method and include its lithium ion battery |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101428781B (en) * | 2008-12-08 | 2011-01-19 | 广州丰江电池新技术有限公司 | Conglobation type nanostructured lithium iron phosphate anode material and method for producing the same |
-
2019
- 2019-09-02 CN CN201910822457.3A patent/CN111682202B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102208627A (en) * | 2011-05-11 | 2011-10-05 | 华南理工大学 | Method for preparing LiFePO4/C composite anode material by spray drying |
| CN102593451A (en) * | 2012-03-12 | 2012-07-18 | 中国科学院过程工程研究所 | Lithium manganese phosphate nanofiber as anode material of lithium ion battery and preparation method of lithium manganese phosphate nanofiber |
| CN102945962A (en) * | 2012-12-07 | 2013-02-27 | 山东铂源锂电科技有限公司 | Nanorod-shaped lithium iron phosphate material and preparation method thereof |
| CN104300119A (en) * | 2013-07-17 | 2015-01-21 | 东莞市长安东阳光铝业研发有限公司 | Preparation method for lithium iron phosphate cathode material |
| CN104701536A (en) * | 2013-12-09 | 2015-06-10 | 青岛平度市旧店金矿 | Process for preparing high-performance lithium battery positive electrode material through spray drying method |
| CN104752692A (en) * | 2013-12-30 | 2015-07-01 | 北京有色金属研究总院 | Preparation method for LiFePO4/C composite anode material |
| CN103996846A (en) * | 2014-04-14 | 2014-08-20 | 江苏中欧材料研究院有限公司 | Preparation method for lithium iron phosphate positive electrode material with controllable particle size |
| WO2016141706A1 (en) * | 2015-03-10 | 2016-09-15 | 中国科学院过程工程研究所 | Composite-coated lithium iron phosphate and preparation method therefor, and lithium ion battery |
| CN106229505A (en) * | 2016-08-17 | 2016-12-14 | 深圳市贝特瑞纳米科技有限公司 | A kind of high-density spherical nano lithium iron phosphate material and preparation method thereof and the lithium ion battery comprising it |
| CN107394152A (en) * | 2017-07-17 | 2017-11-24 | 深圳市贝特瑞纳米科技有限公司 | The spherical composite of the high graphene-based LiFePO4 of conductance, its preparation method and include its lithium ion battery |
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