CN109904450B - Preparation method of carbon-coated sodium vanadium phosphate composite positive electrode material - Google Patents
Preparation method of carbon-coated sodium vanadium phosphate composite positive electrode material Download PDFInfo
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Abstract
The invention discloses a preparation method of a carbon-coated vanadium sodium phosphate composite anode material, which comprises the following steps: firstly, mixing and reacting a water solution containing a vanadium source and a phosphorus source to obtain a reaction solution A; secondly, mixing the materials with reducing sugar for reaction to obtain reaction liquid C; when the phosphorus source does not contain sodium atoms, the material is obtained after the reaction liquid A and the sodium source are mixed and reacted; when the phosphorus source contains sodium atoms, the material is reaction liquid A; and thirdly, spray drying and calcining the reaction liquid C to obtain the catalyst. In the preparation process, the traditional long-time high-temperature calcination in the later period is not needed, so that the energy consumption is obviously reduced, and the large-scale production is easy to realize; the obtained material has good consistency, the particle size of 2-20 mu m, high specific capacity, excellent rate performance and good charge-discharge cycle stability, improves the electrochemical performance and energy density of the battery, is beneficial to the practical development of the sodium ion battery, is suitable for commercial large-scale production, and has wide application prospect in the fields of large-scale and high-power battery energy storage.
Description
Technical Field
The invention relates to the technical field of secondary battery electrode materials, in particular to a preparation method of a carbon-coated vanadium sodium phosphate composite anode material.
Background
At present, large-scale energy storage represented by a smart grid puts higher requirements on an energy storage technology, and a secondary battery system applied to the field of large-scale energy storage needs to be developed urgently. Due to the special application scene, the requirements are that the energy-saving power supply has the characteristics of environmental protection, low cost, safety, reliability and long service life, and simultaneously the requirements of electrochemical performance indexes such as energy density, power density, multiplying power performance and the like are considered. Therefore, developing energy storage battery systems that can meet these requirements is a significant technical challenge facing the materials and energy field. The radius of sodium ions is larger than that of lithium ions, and the reversible de-intercalation reaction requires that the material structure has larger sodium-containing sites and ion migration channels. The material of the sodium super ion conductor (NASICON) structure has an open 3D crystal framework structure, and is very favorable for the rapid diffusion and migration of sodium ions. At present, developed positive electrode materials suitable for sodium ion batteries comprise binary or ternary oxides of sodium vanadium phosphate, prussian blue, sodium manganate, sodium vanadate and sodium, wherein the vanadium phosphate sodium composite positive electrode material coated with amorphous carbon has the advantages that the electronic conductivity of the material is greatly improved due to carbon, so that the first-cycle discharge capacity of the material can basically reach more than 110mAh/g and can be close to the theoretical capacity (117.6mAh/g), a higher-voltage discharge platform of 3.4V is provided, excellent comprehensive electrochemical performance is shown, and the positive electrode material is suitable for being applied to large-scale energy storage batteries. However, vanadium and salt compounds thereof have certain toxicity, and the previous research reports that most of the preparation of precursors of carbon-coated vanadium sodium phosphate is realized by a ball milling method, but the ball milling method has huge energy consumption on one hand, and on the other hand, the waste and leakage of materials are difficult to avoid in the preparation and material transfer processes. The vanadium sodium phosphate material has many preparation methods, for example, Changsong et al (electrocimica Acta,2013,103:259-265) and Chinese patent application with publication number CN102496716A synthesize vanadium sodium phosphate cathode material by sol-gel method, but the sol-gel method has the problems of difficult guarantee of reproducibility, long process time, troublesome post-treatment, difficult realization of large-scale production and the like.
Therefore, how to prepare the vanadium phosphate sodium composite cathode material by using a cheap and environment-friendly process route is one of the important challenges in the current process research.
Disclosure of Invention
The invention aims to overcome the defects that in the preparation process of a vanadium sodium phosphate composite cathode material in the prior art, the ball milling method is adopted, the energy consumption is huge, the material waste and leakage are difficult to avoid in the preparation and material transfer processes, and the environment is unfriendly, and the defects that the reproducibility is difficult to ensure, the time consumption is long, the post-treatment is troublesome and the large-scale production is difficult when the sol-gel method is adopted for preparation are overcome, and provides the preparation method of the carbon-coated vanadium sodium phosphate composite cathode material.
The invention solves the technical problems through the following technical scheme.
The invention provides a preparation method of a carbon-coated vanadium sodium phosphate composite positive electrode material, which comprises the following steps:
1) mixing and reacting a water solution containing a vanadium source and a phosphorus source to obtain a reaction solution A, wherein the pH value of the mixing reaction is 4-7;
2) mixing and reacting the materials with reducing sugar for the first time to obtain reaction liquid C;
when the phosphorus source does not contain sodium atoms, the material is reaction liquid B obtained by carrying out a second mixing reaction on the reaction liquid A and the sodium source in the step 1);
when the phosphorus source simultaneously contains sodium atoms, the material is the reaction liquid A in the step 1);
3) and spray drying and calcining the reaction solution C to obtain the catalyst.
The vanadium source in step 1) may be a vanadium source conventionally used in the art, preferably ammonium metavanadate NH4VO3And/or vanadium pentoxide.
In step 1), the aqueous solution containing a vanadium source may be prepared by methods conventional in the art, and is generally prepared by the following steps: dissolving the vanadium source in water, and heating to completely dissolve. The water is typically deionized water. Wherein, the operation and condition of the heating can be conventional in the field, and the temperature after the heating is generally above 90 ℃.
In the step 1), the concentration of the vanadium source in the aqueous solution containing the vanadium source can be conventional in the art, and is preferably 0.1mol/L to 0.5mol/L, such as 0.15mol/L or 0.2 mol/L.
In step 1), the phosphorus source may be a phosphorus source conventionally used in the art, preferably phosphoric acid (H)3PO4) Sodium dihydrogen phosphate (NaH)2PO4) Hydrogen phosphate IIAmmonium ((NH)4)2HPO4) And ammonium dihydrogen phosphate (NH)4H2PO4) One or more of (a).
The molar ratio of vanadium atoms to phosphorus atoms in step 1) may be conventional in the art and is typically 2: 3.
In step 1), the operations and conditions of the mixing reaction may be conventional in the art. The temperature of the mixing reaction is preferably 88 to 95 c, more preferably 90 c. The mixing reaction time is preferably 8-12 min, and more preferably 10 min.
In the step 1), the pH value of the mixing reaction is preferably 5-6.
In the step 2), the reducing sugar generally refers to a saccharide which can generate carbon dioxide under the condition of calcination at 400-450 ℃ and is conventional in the art, and preferably comprises one or more of glucose, sucrose and starch.
In the step 2), the amount of the reducing sugar may be conventional in the art, and preferably, the carbon carbonized by the reducing sugar accounts for 3% to 20% of the total mass of the carbon-coated sodium vanadium phosphate composite positive electrode material, more preferably 4% to 8.5%, for example, 4.4%, 4.5%, 5% or 8.5%.
In step 2), the operations and conditions of the first mixing reaction may be conventional in the art. The temperature of the first mixing reaction is preferably 85 to 95 c, more preferably 90 c. The time of the first mixing reaction is based on the time required for the solution to change from orange color to colorless color and then to turn into dark green colloid, generally 40 min-2 h, for example 60min, at the moment, the poly vanadate ions in the solution are reduced to V3+And VO2+。
In step 2), the sodium source may be a sodium source conventionally used in the art, preferably sodium carbonate (Na)2CO3) Sodium dihydrogen phosphate (NaH)2PO4) One or more of sodium oxalate, sodium citrate and sodium bicarbonate.
The molar ratio of sodium atoms, vanadium atoms and phosphorus atoms in the feed may be conventional in the art and is typically 3:2: 3.
In step 2), the operations and conditions of the second mixing reaction may be conventional in the art. The temperature of the second mixing reaction is preferably 88 to 95 ℃. The time of the second mixing reaction is based on the total release of carbon dioxide, and is generally 8-12 min, for example 10 min.
In step 2), the pH of the second mixing reaction may be conventional in the art, preferably 6 to 9, and more preferably 7.5 to 8.
In the step 3), the concentration of the vanadium ions in the reaction solution C is preferably 0.1-0.5 mol/L, such as 0.2 mol/L.
In step 3), the operation and conditions of the spray drying may be conventional in the art. In the spray drying process, preferably: the inlet temperature is 180-200 ℃, the gas flow is 660-1000L/h, and the feed pump flow is 200-900 mL/h.
In step 3), the calcination operation may be conventional in the art, and generally, the precursor obtained after spray drying is heated to the calcination temperature in a tube furnace under an inert atmosphere. Wherein the rate of temperature rise can be conventional in the art, and is generally 3-8 ℃/min, for example 5 ℃/min. The inert atmosphere may be an atmosphere that does not participate in chemical reactions at the calcination temperature, as is conventional in the art, such as nitrogen or argon.
In the step 3), the calcining temperature can be controlled within the range of 400-600 ℃, preferably within the range of 400-450 ℃. According to the method, under the condition of specific dissolving pH value in the previous step (the pH value of the solution can greatly influence the form of metavanadate ions, and further influence the subsequent reaction process), the mononuclear metavanadate ions are fully polymerized, so that a larger crystal structure can be formed in the sintering process, the polyvanadate can be reduced to the maximum extent, the electrochemically active anode material can be obtained without high-temperature treatment (generally more than 600 ℃) in the traditional preparation process in the later calcining process, and the energy consumption can be reduced to a great extent. If the calcination temperature is too high, for example > 780 ℃ or higher, even new impurities may be formed.
In the step 3), the calcination time can be conventional in the art, and is preferably 6-15 h.
In step 3), the calcination is generally followed by natural cooling.
In the invention, the particle size of the carbon-coated sodium vanadium phosphate composite anode material can be 2-5 μm. In the carbon-coated sodium vanadium phosphate composite cathode material, the thickness of the carbon coating layer can be conventional in the art, and is generally 6nm to 15nm, for example 10nm or 11 nm.
In the present invention, the above-mentioned "first time" and "second time" have no special meaning, and are used only for distinguishing different mixing reactions.
On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain the preferred embodiments of the invention.
The reagents and starting materials used in the present invention are commercially available.
The positive progress effects of the invention are as follows:
1) in the preparation method of the invention, the raw materials are completely dissolved in water instead of suspension liquid in the conventional process; the polymerization of the mononuclear metavanadate is realized through a specific feeding sequence, so that a structure with a larger crystal form is formed in the sintering process; then the precursor is obtained by high-efficiency spray drying, so that the full utilization of the raw materials and zero environmental pollution emission can be realized; compared with a solid phase method, most of pentavalent vanadium ions in the method can be reduced to trivalent through reducing sugar in the solution, the traditional long-time high-temperature calcination in the later period is not needed, the energy consumption is obviously reduced, and the large-scale production is easy to realize.
In addition, the invention selects cheap and easily available reducing sugar as the carbon source, and the performance is still excellent while the cost is greatly reduced.
2) The particle size of the prepared precursor can be effectively controlled, and the precursor has uniform particle size, good dispersibility and no agglomeration. The carbon-coated vanadium sodium phosphate composite positive electrode material fired by the precursor has good consistency, can be controlled to be 2-5 mu m, has high specific capacity and better rate performance, and simultaneously shows excellent charge-discharge cycle stability, thereby improving the electrochemical performance and energy density of the sodium ion battery, being beneficial to the practical development of the sodium ion battery, being applicable to commercial large-scale production, and having wide application prospect in the fields of large-scale and high-power battery energy storage.
Drawings
Fig. 1 is a scanning electron microscope image of the sodium vanadium phosphate precursor prepared in example 1.
Fig. 2 is an X-ray diffraction pattern of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1.
Fig. 3 is a scanning electron microscope image of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1.
FIG. 4 is a transmission electron microscope image of monodisperse particles of carbon-coated sodium vanadium phosphate composite prepared in example 2.
FIG. 5 is a charging and discharging summary chart of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1 at a current density of 11.8mA/g-1180 mA/g.
FIG. 6 is a charge-discharge cycle chart of the carbon-coated sodium vanadium phosphate composite cathode material prepared in example 2 at a current density of 118 mA/g.
Fig. 7 is a charge and discharge test graph of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1 and a comparative example at a current density of 117mA/g, wherein a and a are charge and discharge curves of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in the comparative example, and B are charge and discharge curves of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1.
Fig. 8 is an X-ray diffraction pattern of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in the comparative example, in which arrows indicate impurity peaks.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.
In the examples and the comparative examples of the present invention, the morphology of the particles was observed by using a high-resolution field emission scanning electron microscope (Sirion 200), the thickness of the carbon coating layer was measured by using a field emission transmission electron microscope (TALOS F200X), and the carbon content in the material was analyzed by using a thermogravimetric analyzer (Pyris 1 TGA).
Example 1
A preparation method of a carbon-coated sodium vanadium phosphate composite positive electrode material specifically comprises the following steps:
1) weighing 17.5467g of ammonium metavanadate, adding 500mL of deionized water, and heating for dissolving (the heating temperature is generally more than 90 ℃) to obtain an aqueous solution containing a vanadium source (wherein the concentration of the vanadium source is 0.2 mol/L); adding 25.8818g ammonium dihydrogen phosphate, stirring and reacting for 10min under 90 ℃ oil bath to obtain reaction liquid A; the pH value of the reaction solution A is 4;
2) 11.9239g of sodium carbonate is added into the reaction liquid A for mixing reaction, the temperature of the mixing reaction is 88 ℃, the mixing reaction time is 10min, until no carbon dioxide bubbles are generated in the solution, and reaction liquid B is obtained; the pH value of the reaction solution B was 7.5;
in the reaction liquid B, the molar ratio of sodium atoms to vanadium atoms to phosphorus atoms is 3:2: 3;
3) at this temperature, 9.3984g of sucrose was added to the reaction solution B, and the temperature of the mixing reaction was 90 ℃ for 60min until the solution became greenish black and the color did not change any more. Naturally cooling after the reaction is finished to obtain a reaction liquid C (dark green colloidal solution);
4) spray-drying the reaction solution C with the concentration of 0.2mol/L (calculated by vanadium ions) to obtain precursor particles; spray drying parameters: the inlet temperature is 200 ℃, the gas flow is 1000L/h, and the flow of a feed pump is 500 mL/h;
and sintering the obtained precursor in a tubular furnace at the temperature rise rate of 5 ℃/min for 15h at 400 ℃ in the nitrogen atmosphere, and naturally cooling to room temperature to obtain the carbon-coated vanadium sodium phosphate composite cathode material with good dispersibility, wherein the carbon content accounts for 4.4% of the total mass, and the thickness of the carbon-coated layer is 10 nm.
Example 2
A preparation method of a carbon-coated sodium vanadium phosphate composite positive electrode material specifically comprises the following steps:
1) weighing 17.55g of ammonium metavanadate, adding 500mL of deionized water, and heating to dissolve (the heating temperature is more than 90 ℃) to obtain an aqueous solution containing a vanadium source (wherein the concentration of the vanadium source is 0.2 mol/L); adding 27.125g of sodium dihydrogen phosphate, and stirring and reacting for 10min under the condition of oil bath at 95 ℃ to obtain reaction liquid A; the pH value of the reaction solution A is 5;
in the reaction liquid A, the molar ratio of sodium atoms to vanadium atoms to phosphorus atoms is 3:2: 3;
2) at this temperature, 9.4g of sucrose was added to the reaction solution A, and the temperature of the mixing reaction was 90 ℃ for 60min until the solution became greenish black and the color did not change any more. Naturally cooling after the reaction is finished to obtain a reaction solution D (dark green colloidal solution);
4) spray-drying the reaction solution C with the concentration of 0.2mol/L (calculated by vanadium ions) to obtain precursor particles; spray drying parameters: the inlet temperature is 200 ℃, the gas flow is 1000L/h, and the flow of a feed pump is 500 mL/h;
and sintering the obtained precursor in a tubular furnace at the temperature rise rate of 5 ℃/min for 15h at 400 ℃ in the nitrogen atmosphere, and naturally cooling to room temperature to obtain the carbon-coated vanadium sodium phosphate composite cathode material with good dispersibility, wherein the carbon content accounts for 4.5% of the total mass, and the thickness of the carbon-coated layer is about 10 nm.
Example 3
1) Weighing 17.5467g of ammonium metavanadate, adding 500mL of deionized water, and heating and dissolving at 95 ℃ to obtain an aqueous solution with the concentration of 0.2 mol/L; adding 25.8818g ammonium dihydrogen phosphate, stirring and reacting for 10min under 90 ℃ oil bath to obtain reaction liquid A; the pH value of the reaction solution A is 4;
2) 11.9239g of sodium carbonate is added into the reaction liquid A for mixing reaction, the temperature of the mixing reaction is 88 ℃, the mixing reaction time is 10min, until no carbon dioxide bubbles are generated in the solution, and reaction liquid B is obtained; the pH value of the reaction solution B was 7.5;
in the reaction liquid B, the molar ratio of sodium atoms to vanadium atoms to phosphorus atoms is 3:2: 3;
3) at this temperature, 18.88g of glucose was added to the reaction solution B, and the temperature of the mixing reaction was 90 ℃ for 70min until the solution became greenish black and the color did not change any more. Naturally cooling after the reaction is finished to obtain a reaction liquid C (dark green colloidal solution);
4) spray drying the reaction solution C (calculated by vanadium) with the concentration of 0.2mol/L to obtain precursor particles; spray drying parameters: the inlet temperature is 200 ℃, the gas flow is 1000L/h, and the flow of a feed pump is 500 mL/h;
and sintering the obtained precursor in a tubular furnace at the temperature rise rate of 5 ℃/min for 15h at 400 ℃ in the nitrogen atmosphere, and naturally cooling to room temperature to obtain the carbon-coated vanadium sodium phosphate composite cathode material with good dispersibility, wherein the carbon content accounts for 8.5% of the total mass, and the thickness of the carbon-coated layer is 11 nm.
Comparative example
A preparation method of a carbon-coated sodium vanadium phosphate composite positive electrode material specifically comprises the following steps:
1) weighing 35.0934g of ammonium metavanadate, adding into 1000mL of deionized water, and heating and dissolving at 90 ℃ to obtain an aqueous solution containing a vanadium source (wherein the concentration of the vanadium source is 0.15 mol/L); adding 11.9239g of sodium carbonate, stirring and reacting for 20min under 90 ℃ oil bath to obtain reaction liquid A; the pH value of the reaction solution A was 12.5;
2) adding 53.99g of ammonium dihydrogen phosphate into the reaction liquid A for mixed reaction at the temperature of 90 ℃ for 20 min; obtaining reaction liquid B; the pH value of the reaction solution B is 8;
in the reaction liquid B, the molar ratio of sodium atoms to vanadium atoms to phosphorus atoms is 3:2: 3;
3) keeping the temperature, adding 18.7968g of sucrose (the carbon content of the carbonized sucrose accounts for 4 percent of the total mass of the carbon-coated vanadium sodium phosphate composite anode material) into the reaction liquid B, and carrying out mixing reaction at 90 ℃ for 60 min; until the solution turned greenish black and no further color change occurred. Naturally cooling after the reaction is finished to obtain a reaction liquid C (dark green colloidal solution);
4) spray drying the reaction solution C with the concentration of 0.15mol/L to obtain precursor particles; spray drying parameters: the inlet temperature was 200 ℃, the gas flow rate was 1000L/h, and the feed pump flow rate was 500 mL/h.
And sintering the obtained precursor in a tubular furnace at the temperature rise rate of 5 ℃/min for 15h at 400 ℃ in the nitrogen atmosphere, and naturally cooling to room temperature to obtain the carbon-coated vanadium sodium phosphate composite cathode material with good dispersibility.
Effects of the embodiment
Fig. 1 is a scanning electron microscope image of the sodium vanadium phosphate precursor prepared in example 1. From the figure, it can be seen that sodium vanadium phosphate has good crystallinity, sharp peak shape and good NASICON structural phase.
Fig. 2 is an X-ray diffraction pattern of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1. As can be seen from fig. 2, the product is a carbon-coated vanadium sodium phosphate composite positive electrode material.
Fig. 3 is a scanning electron microscope image of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1. As can be seen from FIG. 3, the particle size of this material was about 2 μm, and the particle size distribution was uniform.
FIG. 4 is a transmission electron microscope image of monodisperse particles of carbon-coated sodium vanadium phosphate composite prepared in example 2. As can be seen from fig. 4, in the material, the vanadium sodium phosphate crystal particles are embedded in the conductive carbon layer, and the carbon layer network is beneficial to the rapid transmission of sodium ions and electrons in the battery charging and discharging process, and is beneficial to limiting the volume expansion of the vanadium sodium phosphate crystal particles.
The positive electrode materials prepared in examples and comparative examples were subjected to electrochemical performance tests. Electrode manufacturing and battery assembly: weighing the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in the example 1, conductive carbon black and a binder PVDF according to the mass ratio of 8:1:1, adding a proper amount of 1-methyl-2-pyrrolidone (NMP), fully mixing, grinding uniformly, coating on an aluminum foil, drying at 120 ℃ in a vacuum drying oven for 12 hours, cooling and blanking into a wafer with the diameter of 14 mm. In an argon atmosphere glove box, a CR2016 button cell was assembled with sodium metal as the negative electrode, a microporous polypropylene membrane as the separator, and a 1M NaPF6/EC + EMC + FEC (1:1:0.02) solution as the electrolyte. The cell tests were all performed on a blue test system at a test temperature of 25 ℃.
And carrying out charge and discharge tests on the battery within the voltage range of 2.0V-4.0V.
Fig. 5 is a charging and discharging summary chart of the carbon-coated vanadium sodium phosphate composite positive electrode material prepared in example 1 at a current density of 11.8mA/g-1180mA/g, which shows that the carbon-coated vanadium sodium phosphate composite material prepared under the experimental conditions requiring the best requirements has the optimal capacity expression and rate cycle performance as a positive electrode of a sodium ion battery. The capacity density can reach 113mAh/g under the charge and discharge rate of 0.1C, the capacity density can reach 105mAh/g under the charge and discharge rate of 0.5C, the rate capacity density can reach 82mAh/g under the charge and discharge rate of 10C, the rate capacity density can reach 101mAh/g under the charge and discharge rate of 1C, the rate capacity density can reach 92mAh/g under the charge and discharge rate of 5C, and after 10 cycles of high rate circulation, the charge and discharge of the positive electrode material can still reach 101mAh/g under the charge and discharge rate of 1C.
The button cell made of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 2 and the comparative example was prepared according to the above-described method.
FIG. 6 is a charge-discharge cycle chart of the carbon-coated sodium vanadium phosphate composite cathode material prepared in example 2 at a current density of 118 mA/g. As can be seen from fig. 6, after 100 cycle cycles, the battery capacity retention rate was 94%, the coulombic efficiency was 99.7%, after 200 cycle cycles, the battery capacity retention rate was 91, the coulombic efficiency was 99.5%, after 300 cycle cycles, the battery capacity retention rate was 80%, and the coulombic efficiency was 99.5%.
Fig. 7 is a charge and discharge test graph of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1 and a comparative example at a current density of 117mA/g, wherein a and a are charge and discharge curves of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in the comparative example, and B are charge and discharge curves of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in example 1. As can be seen from FIG. 7, the capacity of the carbon-coated vanadium sodium phosphate composite cathode material prepared by the comparative example is only 77mAh/g at a rate of 1C. This is because the order of addition of ammonium dihydrogen phosphate and sodium carbonate is changed in the comparative example, so that the metavanadate ions are not highly polymerized in the solution stage, and the crystal crystallinity and the electrochemical performance are poor after low-temperature calcination.
Fig. 8 is an X-ray diffraction pattern of the carbon-coated sodium vanadium phosphate composite positive electrode material prepared in the comparative example, in which arrows indicate impurity peaks. During the preparation of the product of the comparative example, due to the significant change in the order of addition of the raw materials, the material was observed to have some distinct impurity peaks from the XRD spectrum, and the capacity at 1C rate of the comparative example product was only 77mAh/g, as described above.
The material prepared in the embodiment 3 is used as the positive electrode material of the sodium-ion battery at room temperature, the metallic sodium is used as the counter electrode, the charging and discharging capacity of 117mA/g is 83mAh/g in the range of 2.0V-4.0V, the performance is reduced compared with that of the embodiment 1(113mA/g), and the carbon layer is too thick to block the migration of sodium ions when the carbon content is too high (or the material has poor electron conductivity when the carbon content is too low), so that the electrochemical performance expression of the material is not facilitated.
For comparison, the data from examples 1-3, comparative example are listed in table 1, below.
TABLE 1
Claims (18)
1. A preparation method of a carbon-coated sodium vanadium phosphate composite positive electrode material is characterized by comprising the following steps:
1) mixing and reacting a water solution containing a vanadium source and a phosphorus source to obtain a reaction solution A, wherein the pH value of the mixing reaction is 4-7;
2) mixing and reacting the materials with reducing sugar for the first time to obtain reaction liquid C; the raw materials are completely dissolved in water;
when the phosphorus source does not contain sodium atoms, the material is reaction liquid B obtained by carrying out a second mixing reaction on the reaction liquid A and the sodium source in the step 1); the pH value of the second mixing reaction is 6-9;
when the phosphorus source simultaneously contains sodium atoms, the material is the reaction liquid A in the step 1);
the polymerization of the mononuclear metavanadate is realized through the feeding sequence;
3) the reaction solution C is obtained after spray drying and calcining;
the reducing sugar in the step 2) is a saccharide which generates carbon dioxide under the condition of calcining at 400-450 ℃; the amount of the reducing sugar is 4-5% of the total mass of the carbon-coated vanadium sodium phosphate composite anode material, wherein the carbon is carbonized by the reducing sugar.
2. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein the vanadium source in the step 1) is ammonium metavanadate;
and/or, in step 1), the aqueous solution containing the vanadium source is prepared by the following steps: dissolving a vanadium source in water, and heating to completely dissolve the vanadium source;
and/or in the step 1), the concentration of the vanadium source in the aqueous solution containing the vanadium source is 0.1-0.5 mol/L;
and/or, in the step 1), the phosphorus source is one or more of phosphoric acid, sodium dihydrogen phosphate, diammonium hydrogen phosphate and ammonium dihydrogen phosphate.
3. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 1), the concentration of the vanadium source in the aqueous solution containing the vanadium source is 0.15mol/L or 0.2 mol/L.
4. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 1), the temperature of the mixing reaction is 88-95 ℃;
and/or in the step 1), the mixing reaction time is 8-12 min.
5. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 4, wherein the temperature of the mixing reaction in the step 1) is 90 ℃.
6. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 4, wherein in the step 1), the mixing reaction time is 10 min.
7. The preparation method of the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 1), the pH value of the mixing reaction is 5-6.
8. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 2), the reducing sugar comprises one or more of glucose, sucrose and starch;
and/or in the step 2), the amount of the reducing sugar is 4-4.5% of the total mass of the carbon-coated vanadium sodium phosphate composite positive electrode material, wherein the carbon is carbonized by the reducing sugar.
9. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 8, wherein the amount of the reducing sugar is such that carbon carbonized by the reducing sugar accounts for 4.4% of the total mass of the carbon-coated sodium vanadium phosphate composite positive electrode material.
10. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 8, wherein the amount of the reducing sugar is such that carbon carbonized by the reducing sugar accounts for 4.5% of the total mass of the carbon-coated sodium vanadium phosphate composite positive electrode material.
11. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 2), the temperature of the first mixing reaction is 85-95 ℃;
and/or in the step 2), the time of the first mixing reaction is 40 min-2 h.
12. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 11, wherein in the step 2), the temperature of the first mixing reaction is 90 ℃;
and/or in the step 2), the time of the first mixing reaction is 60 min.
13. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 2), the sodium source is one or more of sodium carbonate, sodium dihydrogen phosphate, sodium oxalate, sodium citrate and sodium bicarbonate;
and/or in the step 2), the temperature of the second mixing reaction is 88-95 ℃;
and/or in the step 2), the time of the second mixing reaction is 8-12 min.
14. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 13, wherein in the step 2), the time of the second mixing reaction is 10 min.
15. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 13, wherein in the step 2), the pH value of the second mixing reaction is 7.5-8.
16. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 1, wherein in the step 3), the concentration of vanadium ions in the reaction solution C is 0.1-0.5 mol/L;
and/or, in step 3), the spray drying conditions are: the inlet temperature is 180-200 ℃, the gas flow is 660-1000L/h, and the flow of the feed pump is 200-900 mL/h;
and/or in the step 3), the calcining temperature is 400-600 ℃;
and/or in the step 3), the calcining time is 6-15 h.
17. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 16, wherein in the step 3), the concentration of the reaction solution C is 0.2mol/L in terms of vanadium ions.
18. The method for preparing the carbon-coated sodium vanadium phosphate composite positive electrode material according to claim 16, wherein in the step 3), the calcining temperature is 400 to 450 ℃.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102074691A (en) * | 2010-12-27 | 2011-05-25 | 浙江大学 | Method for preparing flaky lithium vanadium phosphate cathode material of lithium ion battery |
| CN104733731A (en) * | 2015-03-25 | 2015-06-24 | 天津大学 | Method for preparing uniform carbon-coated vanadium phosphate sodium material |
| CN105336924A (en) * | 2015-09-25 | 2016-02-17 | 中南大学 | Preparation method of carbon coated vanadium sodium phosphate positive electrode material |
| CN106410193A (en) * | 2016-11-11 | 2017-02-15 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for preparing vanadium sodium phosphate and vanadium phosphate serving as anode material of sodium ion battery |
| CN107611367A (en) * | 2017-08-04 | 2018-01-19 | 中南大学 | A kind of porous spherical carbon coating vanadium phosphate sodium composite positive pole and preparation method thereof |
| KR20180046619A (en) * | 2016-10-28 | 2018-05-09 | 전남대학교산학협력단 | Method for preparing electrode material and electrode material prepared thereby |
-
2019
- 2019-03-18 CN CN201910203315.9A patent/CN109904450B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102074691A (en) * | 2010-12-27 | 2011-05-25 | 浙江大学 | Method for preparing flaky lithium vanadium phosphate cathode material of lithium ion battery |
| CN104733731A (en) * | 2015-03-25 | 2015-06-24 | 天津大学 | Method for preparing uniform carbon-coated vanadium phosphate sodium material |
| CN105336924A (en) * | 2015-09-25 | 2016-02-17 | 中南大学 | Preparation method of carbon coated vanadium sodium phosphate positive electrode material |
| KR20180046619A (en) * | 2016-10-28 | 2018-05-09 | 전남대학교산학협력단 | Method for preparing electrode material and electrode material prepared thereby |
| CN106410193A (en) * | 2016-11-11 | 2017-02-15 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for preparing vanadium sodium phosphate and vanadium phosphate serving as anode material of sodium ion battery |
| CN107611367A (en) * | 2017-08-04 | 2018-01-19 | 中南大学 | A kind of porous spherical carbon coating vanadium phosphate sodium composite positive pole and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| "Effect of Carbon Matrix Dimensions on the Electrochemical Properties of Na3V2(PO4)3 Nanograins for High Performance Symmetric Sodium-Ion Batteries";Shuo Li等;《Adv. Mater.》;20140314;第26卷;第3545-3553页 * |
| "Na3V2(PO4)3: an advanced cathode for sodium-ion batteries"，;Xianghua Zhang等;《Nanoscale》;20190102;第11卷;第2556-2576页 * |
| "Sequentially-processed Na3V2(PO4)3 for cathode material of aprotic sodium ion battery"，;Junling Xu等;《Nano Energy》;20180509;第50卷;第323-330页 * |
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