WO2017036069A1 - V2o5 hollow micron wire ball with nanowire three-dimensional winding structure and preparation method therefor and use thereof - Google Patents

Abstract

The present invention relates to a V₂O₅ hollow micron wire ball with a nanowire three-dimensional winding structure and a preparation method therefor. The V₂O₅ hollow micron wire ball is prepared by using the following method, comprising the following steps: (1) weighing a vanadium pentoxide sol, and diluting in deionized water to obtain a solution; (2) adding an organic solution to the solution obtained in step (1) as a solvent; (3) adding trihydroxymethyl aminomethane to the solution obtained in step (2), and performing ultrasonic treatment for 0.5-2 h; (4) transferring the reactants obtained in step (3) into a reaction kettle for a hydrothermal reaction, taking the reactants out of the reaction kettle, and naturally cooling to room temperature; (5) centrifugally filtering the products obtained in step (4), washing with absolute ethyl alcohol, and drying in an oven to obtain a blue precursor powder; and (6) putting the products obtained in step (5) into a muffle furnace for calcining to obtain the V₂O₅ hollow micron wire ball. The present invention has the beneficial effects of exhibiting an excellent cycle stability and high rate characteristics, and the V₂O₅ hollow micron wire ball is a potential application material for a lithium ion battery of high magnification rate and long life.

Description

V2O5 hollow micron wire ball with nanowire three-dimensional winding structure and preparation method and application thereof Technical field

The invention belongs to the field of nano materials and electrochemical technology, and particularly relates to a V ₂ O ₅ hollow micron wire ball with a three-dimensional winding structure of nanowires and a preparation method thereof, and the material can be used as a positive active material of a high-rate lithium ion battery.

Background technique

Lithium-ion batteries have been widely used in the field of energy storage due to their high operating voltage, high energy density and long service life. However, its application in large-scale energy storage such as electric vehicles is still limited by its rate performance and power density. These can be achieved by constructing an electrode material having a special structure. In the positive electrode material, the V ₂ O ₅ layered structure is widely used because it can reversibly deintercalate lithium ions and has the advantages of abundant resources and high theoretical capacity. However, there are still two major problems, namely, poor rate performance and cycle stability problems caused by slow dynamics and structural instability.

In recent years, many studies have shown that the construction of nanomaterials such as nanowires, nanobelts, etc. can effectively reduce the diffusion distance of lithium ions at the nanometer scale, and improve the rate performance of materials from high kinetics. However, these nanomaterials have the disadvantage of low tap density, and agglomeration occurs during the cycle. Structures assembled from one-dimensional nanomaterials, such as coil structures, have been widely studied because they can retain the excellent properties of one-dimensional nanomaterials, and can also increase the tap density and improve the volumetric energy density on a three-dimensional scale.

Summary of the invention

The technical problem to be solved by the present invention is to provide a V ₂ O ₅ hollow micron wire ball which is three-dimensionally wound by nanowires and a preparation method thereof, and has a wide source of raw materials, simple preparation process and low cost. The resulting V ₂ O ₅ hollow micron spheres, which are three-dimensionally wound by nanowires, have excellent electrochemical properties.

The technical solution adopted by the present invention to solve the above technical problem is: a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, which has a diameter of 4-10 micrometers, is wound by nanowires, and forms a hollow porous structure. It is prepared by the following method, including the following steps:

1) taking a vanadium pentoxide sol and diluting it in deionized water to obtain a solution;

2) in the solution obtained in the step 1), adding an organic solution as a solvent;

3) in the solution obtained in step 2), adding hydroxymethylaminomethane, ultrasonic 0.5-2h;

4) The reactant obtained in the step 3) is transferred to a hydrothermal reaction in the reaction vessel, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) is calcined in a muffle furnace to obtain a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires.

According to the above scheme, the molar amount of vanadium pentoxide described in the step 1) is 0.3-0.7 mmol, the volume of the vanadium sol obtained after dilution is 6-14 mL; the volume of the organic solvent described in the step 2) is 40-60 mL; 3) The amount of the trishydroxymethylaminomethane is from 1.0 to 3.0 g.

According to the above scheme, the organic solvent described in the step 2) is isopropanol or n-propanol.

According to the above scheme, the hot water temperature in step 4) is 180-220 ° C, and the time is 1-24 h.

According to the above scheme, the calcination temperature in the step 6) is 350-600 ° C, and the time is 1-8 h.

The preparation method of the V ₂ O ₅ hollow micron wire ball with the nanowire three-dimensional winding structure comprises the following steps:

1) taking a vanadium pentoxide sol and diluting it in deionized water to obtain a solution;

2) in the solution obtained in the step 1), adding an organic solution as a solvent;

3) in the solution obtained in step 2), adding hydroxymethylaminomethane, ultrasonic 0.5-2h;

4) The reactant obtained in the step 3) is transferred to a hydrothermal reaction in the reaction vessel, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) is calcined in a muffle furnace to obtain a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires.

The V ₂ O ₅ hollow micron wire ball with the nanowire three-dimensional winding structure is used as a positive electrode active material of a lithium ion battery.

The invention greatly shortens the lithium ion diffusion distance on the one-dimensional nanowire scale, and utilizes the hollow porous structure to buffer the volume change of the lithium ion in the deintercalation process to ensure the structural stability, thereby effectively improving the electrochemical performance of the material. . When the material is used as the positive active material of lithium battery, the constant current charge and discharge test at 100mA/g high current density shows that the first discharge specific capacity can reach 145.3mAh/g, and after 50 cycles, it is 137.2mAh/g. The rate is 94.4%. At a high current density of 2000 mA/g, its capacity can reach 129.3 mAh/g after activation. The results show that the V ₂ O ₅ hollow micron spheres, which are three-dimensionally wound by nanowires, have excellent cycle stability and high rate characteristics, and are potential application materials for high-power, long-life lithium batteries.

In addition, the unique one-dimensional nanostructure assembly method greatly improves the tap density of the nano material, and effectively improves the structural stability of the material, thereby greatly improving the rate performance.

The beneficial effects of the present invention are that a three-dimensional hollow porous V ₂ O ₅ coil is obtained by a two-step solvothermal-annealing heat treatment. This three-dimensional coil structure not only retains the excellent properties of the one-dimensional nanomaterial, but also exhibits a significantly improved tap density. When used as a positive electrode active material for lithium ion batteries, the V ₂ O ₅ coil exhibits excellent cycle stability and high rate characteristics, and is a potential application material for high-rate, long-life lithium ion batteries. The invention has mild reaction conditions, simple process, meets the requirements of green chemistry, and has low requirements on equipment, which is favorable for market promotion.

DRAWINGS

1 is an XRD pattern of a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to Embodiment 1 of the present invention;

2 is an SEM image of a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to Embodiment 1 of the present invention;

3 is a TEM image of a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to Embodiment 1 of the present invention;

4 is a view showing the synthesis mechanism of a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of a nanowire according to Embodiment 1 of the present invention;

5 is a BET and pore size distribution diagram of a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to Embodiment 1 of the present invention;

6 is a cycle diagram of constant current charge and discharge of a V ₂ O ₅ hollow micron microsphere having a nanowire three-dimensionally wound structure at a high current density (100 mA g ⁻¹ ) according to Embodiment 1 of the present invention;

7 is a cycle diagram of constant current charge and discharge of a V ₂ O ₅ hollow micron sphere having a nanowire three-dimensionally wound structure at a high current density (2000 mA g ⁻¹ ) according to Embodiment 1 of the present invention;

8 is a magnification diagram of a V ₂ O ₅ hollow micron microsphere having a nanowire three-dimensional winding structure according to Embodiment 1 of the present invention, which is discharged at a low current density (100 mA g ⁻¹ ) and discharged at different current densities.

detailed description

In order to better understand the present invention, the contents of the present invention will be further clarified below with reference to the embodiments, but the contents of the present invention are not limited to the following embodiments.

Example 1:

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.5 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 50 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 2.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) is transferred to a reaction vessel at 200 ° C for 2 h, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined at 400 ° C for 5 h in a muffle furnace to obtain a V ₂ O ₅ hollow micron ball which was three-dimensionally wound by nanowires.

As shown in FIG. 4, the synthesis mechanism of the present invention is that the synthesis process includes two processes of pre-solvent heat and post-calcination. During the ultrasonic process, nanowires are formed due to charge interaction and nucleation reaction. Due to the decrease of surface energy, the nanowires self-assemble to form a linear sphere structure. Finally, the V ₂ O ₅ hollow micron wires which are three-dimensionally wound by nanowires are obtained by calcination heat treatment. ball. The hybrid structure can not only retain the excellent characteristics of the nanowire, but also effectively shorten the diffusion distance of the lithium ion, and can also effectively utilize the hollow porous structure to effectively buffer the expansion and contraction of the electrode material during charging and discharging, and effectively improve the three-dimensional structure. The density is tapped to obtain long-life, high-rate electrochemical performance.

The V ₂ O ₅ hollow micron wire ball in which the product of the present example is three-dimensionally wound by nanowires is taken as an example, and the structure thereof is determined by an X-ray diffractometer. As shown in Fig. 1, the X-ray diffraction pattern (XRD) showed that the three-dimensional porous structure vanadium oxide was V ₂ O ₅ (JCPDS card number 01-089-0611), and no other impurity phase. As shown in Fig. 2, field emission scanning electron microscopy (FESEM) tests show that the V ₂ O ₅ hollow micron spheres, which are three-dimensionally wound by nanowires, are 4-10 micrometers in diameter and are wound by one-dimensional nanowires. As shown in FIG. 3, transmission electron microscopy (TEM) and high resolution transmission electrode (HRTEM) tests indicate that the nanostructure has a hollow porous structure. As shown in FIG. 4, the formation of the V ₂ O ₅ hollow micron spheres, which are three-dimensionally wound by nanowires, mainly undergoes the formation of the prior nanowires and the subsequent self-assembly of the surface energy and the post-calcination heat treatment. As shown in Fig. 5, the nitrogen adsorption desorption experiment of the V ₂ O ₅ hollow micron ball which is three-dimensionally wound by nanowires shows that the specific surface area is 20.2 m ² /g.

The V ₂ O ₅ hollow micron wire ball formed by three-dimensional winding of the nanowire prepared by the invention is used as a positive electrode active material of a lithium ion battery, and the remaining steps of the preparation method of the lithium ion battery are the same as the usual preparation method. The preparation method of the positive electrode sheet is as follows, using V ₂ O ₅ hollow micron wire ball which is three-dimensionally wound by nanowires as an active material, acetylene black as a conductive agent, polytetrafluoroethylene as a binder, active material, acetylene black, poly The mass ratio of tetrafluoroethylene is 60:30:10; after they are thoroughly mixed in proportion, a small amount of isopropyl alcohol is added, and the mixture is uniformly ground, and an electrode sheet of about 0.2 mm thick is pressed on the roll machine; the pressed positive electrode sheet is placed. The oven was dried at 70 ° C for 24 hours and then used. 1M LiPF _{6 is} dissolved in ethylene carbonate (EC) and dimethyl carbonate (DMC) as an electrolyte, lithium sheet is a negative electrode, and CR 2016 stainless steel is assembled into a button-type lithium ion battery.

Taking three-dimensional porous V ₂ O ₅ as an example, when the material is used as a positive active material for lithium batteries, as shown in Fig. 6, the constant current charge and discharge test at a current density of 100 mA/g, the first discharge specific capacity can reach 145.3 mAh/g. After 10 cycles, it was 137.2 mAh/g, and the capacity retention rate was 94.4%. When the current density is increased to 2000 mA/g, the capacity can reach 129.3 mAh/g after activation, and the capacity remains at 112.2 mAh/g after 100 cycles (as shown in Fig. 7). In the case of low current density (100mA g ^-1 ) charging and discharge at different current densities, when the discharge current is as high as 9750mA/g, the discharge specific capacity is still as high as 94.8mAh/g (as shown in Figure 8). The V ₂ O ₅ hollow micron ball, which is formed by three-dimensional winding of nanowires, has excellent cycle performance and rate characteristics, and is a potential application material for high-power, long-life lithium ion batteries.

Example 2:

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.3 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 50 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 1.0 g of trishydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) is transferred to a reaction vessel at 200 ° C for 24 h, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined at 400 ° C for 5 h in a muffle furnace to obtain a V ₂ O ₅ hollow micron ball which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 142 mAh/g, 133.2 mAh/g after 50 cycles, and the capacity retention rate was 93.8%.

Example 3:

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.5 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 40 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 2.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) was transferred to a reaction vessel at 220 ° C for 1 h, and the reaction vessel was taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined in a muffle furnace at 425 ° C for 3 h to obtain a V ₂ O ₅ hollow micron sphere which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 144.1 mAh/g, 132.3 mAh/g after 50 cycles, and the capacity retention rate was 91.8%.

Example 4:

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.5 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 60 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 3.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) was transferred to a reaction vessel at 200 ° C for 2 h, and the reaction vessel was taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined at 400 ° C for 5 h in a muffle furnace to obtain a V ₂ O ₅ hollow micron ball which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 141.8 mAh/g, which was 133.2 mAh/g after 50 cycles, and the capacity retention rate was 93.9%.

Example 5:

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.7 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 50 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 3.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) is transferred to a reaction vessel at 200 ° C for 2 h, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined in a muffle furnace at 375 ° C for 7 h to obtain a V ₂ O ₅ hollow micron sphere which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 139 mAh/g, which was 129.8 mAh/g after 50 cycles, and the capacity retention rate was 93.4%.

Example 6

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.5 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 50 mL of isopropanol is added as a solvent;

3) In the solution obtained in step 2), 2.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) is transferred to a reaction kettle at 180 ° C for 24 h, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined in a muffle furnace at 425 ° C for 5 h to obtain a V ₂ O ₅ hollow micron sphere which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 143.7 mAh/g, which was 133.2 mAh/g after 50 cycles, and the capacity retention rate was 92.7%.

Example 7

A method for preparing a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires, comprising the following steps:

1) Measure 0.5 mmol of V ₂ O ₅ sol and dilute to 10 mL with deionized water;

2) In the solution obtained in the step 1), 50 mL of n-propanol is added as a solvent;

3) In the solution obtained in step 2), 2.0 g of tris-hydroxymethylaminomethane was added and sonicated for 30 min;

4) The reactant obtained in the step 3) is transferred to a reaction vessel at 200 ° C for 24 h, and the reaction vessel is taken out and naturally cooled to room temperature;

5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol for 3-5 times, and dried in an oven to obtain a blue precursor powder;

6) The product obtained in the step 5) was calcined at 400 ° C for 5 h in a muffle furnace to obtain a V ₂ O ₅ hollow micron ball which was three-dimensionally wound by nanowires.

Taking the V ₂ O ₅ hollow micron wire ball which is obtained by three-dimensional winding of the nanowire obtained in the present embodiment as an example, when the material is used as a positive electrode active material of a lithium battery, the constant current charge and discharge test is performed at a current density of 100 mA/g for the first time. The capacity was 144 mAh/g, which was 135.8 mAh/g after 50 cycles, and the capacity retention rate was 94.3%.

Claims (11)

A V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of a nanowire, having a diameter of 4 to 10 μm, wound by a nanowire, and forming a hollow porous structure, is obtained by the following method, comprising the following steps: 1) taking a vanadium pentoxide sol and diluting it in deionized water to obtain a solution; 2) in the solution obtained in the step 1), adding an organic solution as a solvent; 3) in the solution obtained in step 2), adding hydroxymethylaminomethane, ultrasonic 0.5-2h; 4) The reactant obtained in the step 3) is transferred to a hydrothermal reaction in the reaction vessel, and the reaction vessel is taken out and naturally cooled to room temperature; 5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol, and dried in an oven to obtain a blue precursor powder; 6) The product obtained in the step 5) is calcined in a muffle furnace to obtain a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires. The V ₂ O ₅ hollow micron ball with nanowire three-dimensional winding structure according to claim 1, wherein the molar amount of vanadium pentoxide in step 1) is 0.3-0.7 mmol, and the vanadium sol obtained after dilution The volume of the organic solvent is from 4 to 14 mL; the volume of the organic solvent in the step 2) is from 40 to 60 mL; and the amount of the trishydroxymethylaminomethane in the step 3) is from 1.0 to 3.0 g. The V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 1, wherein the organic solvent in the step 2) is isopropanol or n-propanol. The V ₂ O ₅ hollow micron wire ball with a nanowire three-dimensional winding structure according to claim 1, wherein the water temperature in the step 4) is 180-220 ° C and the time is 1-24 h. The V ₂ O ₅ hollow micron wire ball with a nanowire three-dimensional winding structure according to claim 1, wherein the calcination temperature in the step 6) is 350-600 ° C for 1-8 h. The method for preparing a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 1, comprising the following steps: 1) taking a vanadium pentoxide sol and diluting it in deionized water to obtain a solution; 2) in the solution obtained in the step 1), adding an organic solution as a solvent; 3) in the solution obtained in step 2), adding hydroxymethylaminomethane, ultrasonic 0.5-2h; 4) The reactant obtained in the step 3) is transferred to a hydrothermal reaction in the reaction vessel, and the reaction vessel is taken out and naturally cooled to room temperature; 5) The product obtained in the step 4) is centrifugally filtered, washed with anhydrous ethanol, and dried in an oven to obtain a blue precursor powder; 6) The product obtained in the step 5) is calcined in a muffle furnace to obtain a V ₂ O ₅ hollow micron wire ball having a three-dimensional winding structure of nanowires. The method for preparing a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 6, wherein the molar amount of vanadium pentoxide in the step 1) is 0.3-0.7 mmol, after dilution The volume of the obtained vanadium sol is 6-14 mL; the volume of the organic solvent described in the step 2) is 40-60 mL; and the amount of the trishydroxymethylaminomethane described in the step 3) is 1.0-3.0 g. The method for preparing a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 6, wherein the organic solvent in the step 2) is isopropanol or n-propanol. The method for preparing a V ₂ O ₅ hollow micron microsphere having a nanowire three-dimensional winding structure according to claim 6, wherein the step 4) has a hydrothermal temperature of 180-220 ° C and a time of 1-24 h. The method for preparing a V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 6, wherein the calcination temperature in the step 6) is 350-600 ° C and the time is 1-8 h. The V ₂ O ₅ hollow micron wire ball having a nanowire three-dimensional winding structure according to claim 1 is used as a positive electrode active material of a lithium ion battery.

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