CN106159248A - A kind of preparation method of lithium ion battery Zinc vanadate nanofiber anode material - Google Patents

Abstract

The invention discloses a method for preparing a zinc vanadate nanofiber negative electrode material for a lithium ion battery, which belongs to the technical field of nanometer materials and chemical power sources. The material of the present invention is a zinc vanadate nanofiber material for lithium ion batteries. First, PVP/C ₄ H ₆ ZnO ₄ /C ₁₀ H ₁₄ O ₅ V composite nanofibers are prepared by electrospinning technology, and then calcined at high temperature to obtain Zinc vanadate nanofibers. The preparation method of the present invention has simple process and low production cost. The zinc vanadate nanofibers obtained by the method have large specific surface area, short ion diffusion path, good structure and electrochemical stability, and can be used as lithium-ion batteries. Anode materials have good development prospects.

Description

A kind of preparation method of zinc vanadate nanofiber negative electrode material for lithium ion battery

technical field

The invention relates to a lithium-ion battery nanometer negative electrode material and a preparation method, in particular to a lithium-ion battery zinc vanadate nanofiber negative electrode material and a preparation method; it belongs to the technical field of nanometer materials and chemical power sources.

Background technique

Energy storage has always been one of the hot issues that people pay attention to, especially in recent years, the contradiction between environment and energy has become increasingly serious. Human beings have never stopped on the road to find efficient energy storage devices. Compared with other energy storage devices, lithium-ion batteries have the advantages of environmental protection and no memory effect, and have been widely used in various portable electronic devices. With the rise and development of hybrid electric vehicles and electric vehicles, people have put forward higher requirements on the specific capacity, service life and fast charging and discharging performance of lithium-ion batteries. However, the negative electrode material used in commercial lithium-ion batteries is mainly graphite. The theoretical capacity of graphite materials is only 372mAh/g, which is increasingly unable to meet the current high specific capacity requirements. Therefore, it is necessary to develop new lithium-ion battery anode materials with high specific capacity, high charge-discharge efficiency and long cycle life.

In recent years, a large number of studies have found that transition metal oxides have high theoretical specific capacity and are potential substitute materials for graphite anodes. Among them, the spinel-type composite metal oxide Zn ₂ V ₂ O ₇ has high theoretical specific capacity, environmentally friendly raw materials, low price, and stable cycle performance. Electrospinning technology can be used to prepare nanofibers. Due to the advantages of small fiber diameter and large specific surface area, it can effectively increase the diffusion path of ions and the surface area of electron transmission when used in lithium-ion batteries, thereby improving the reversible capacity and capacity of lithium-ion batteries. cycle life. At present, there are no relevant literature and patent reports on the preparation of Zn ₂ V ₂ O ₇ nanofibers and their use as anode materials for lithium-ion batteries by combining electrospinning technology and high-temperature calcination technology.

Contents of the invention

Aiming at the deficiencies of the prior art, the problem to be solved by the present invention is the preparation and application of zinc vanadate nanofibers for lithium batteries.

The technical solution adopted in the present invention is to prepare PVP/C ₄ H ₆ ZnO ₄ /C ₁₀ H ₁₄ O ₅ V composite nanofibers by electrospinning, and obtain zinc vanadate nanofiber negative electrode materials through high-temperature calcination. The specific steps are as follows :

(1) Weigh a certain amount of PVP and dissolve it in ethanol, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming.

(2) Weigh a certain amount of vanadyl acetylacetonate (C ₁₀ H ₁₄ O ₅ V) and zinc acetate (C ₄ H ₆ ZnO ₄ 2H ₂ O) and dissolve them in DMF, put them into the stirring bar and adjust the appropriate speed , and stirred at room temperature for 12 to 24 hours until a homogeneous solution was formed.

(3) Slowly pour the solution in step (2) into the solution in step (1), and continue stirring at room temperature for 5-6 hours until uniform.

(4) The solution in step (3) is spun in an electrospinning device to obtain a PVP/C ₄ H ₆ ZnO ₄ /C ₁₀ H ₁₄ O ₅ V composite nanofiber membrane, and the spinning voltage is 15 to 25 kV , the receiving distance is 10-20cm, and the spinning speed is 0.3-1.0mL/h.

(5) Put the composite nanofiber membrane obtained in step (4) into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep the temperature for 3-5h, and the heating rate is 0.5-2°C/min, Naturally cool down to room temperature after calcination.

Owing to adopting above-mentioned technical scheme, the present invention has following advantage and effect:

(1) The preparation method of the present invention has a simple process, and zinc vanadate nanofibers can be obtained through electrospinning and calcination.

(2) The zinc vanadate nanofiber negative electrode prepared by the present invention can fully utilize the advantages such as the nanofiber material has large specific surface area, shorter ion diffusion path and good structural stability, and has excellent electrochemical stability, so it can It is widely used as a new type of lithium-ion battery anode material.

Description of drawings

Fig. 1 Scanning electron microscope image of zinc vanadate nanofibers.

Figure 2 Cycle performance diagram of zinc vanadate nanofiber anode material.

detailed description

Example 1

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 15kV, a receiving distance of 15cm, and a spinning speed of 0.5mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ / C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofiber membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep at 500°C for 4h, and the heating rate is 1°C/min, and naturally cool down to room temperature after the calcination, that is, Zinc vanadate nanofibers.

Example 2

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 20kV, a receiving distance of 20cm, and a spinning speed of 0.5mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ / C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofiber membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep at 500°C for 3h, and the heating rate is 0.5°C/min, and naturally cool down to room temperature after the calcination, that is, Zinc vanadate nanofibers.

Example 3

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 15kV, a receiving distance of 20cm, and a spinning speed of 1mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ /C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofibrous membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep at 500°C for 5h, the heating rate is 2°C/min, and naturally cool down to room temperature after the calcination, that is, Zinc vanadate nanofibers.

Example 4

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 25kV, a receiving distance of 15cm, and a spinning speed of 0.8mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ / C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofiber membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep at 500°C for 2h, and the heating rate is 1°C/min, and naturally cool down to room temperature after the calcination, that is, Zinc vanadate nanofibers.

Example 5

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 15kV, a receiving distance of 20cm, and a spinning speed of 0.5mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ / C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofiber membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in air atmosphere, keep at 500°C for 4h, the heating rate is 0.5°C/min, and naturally cool down to room temperature after calcination, that is, Zinc vanadate nanofibers.

Example 6

Weigh 3g of PVP and add it to 8.5g ethanol solution, put it into a stirrer, adjust the appropriate speed, stir at room temperature for 12-24 hours until uniform, and let it stand for defoaming. At the same time, weigh 0.63685g of vanadyl acetylacetonate and 0.26315g of zinc acetate dihydrate and dissolve them in 8.5g of DMF, put them into a stirring bar, adjust the appropriate speed, and stir at room temperature for 12 to 24 hours until uniform. After both have formed a uniform solution, add the DMF solution to the ethanol solution, and continue to stir at room temperature for 5-6 hours until uniform. Then, the prepared spinning solution was spun in a self-made electrospinning device with a spinning voltage of 18kV, a receiving distance of 18cm, and a spinning speed of 1mL/h to obtain PVP/C ₄ H ₆ ZnO ₄ /C ₁₀ H ₁₄ O ₅ V composite nanofibrous membrane. Then put the obtained composite nanofiber membrane into a tube furnace for calcination, raise the temperature from room temperature to 500°C in an air atmosphere, keep at 500°C for 2h, and the heating rate is 1°C/min, and naturally cool down to room temperature after the calcination, that is, Zinc vanadate nanofibers.

Claims (3)

1. the lithium ion battery preparation method of Zinc vanadate nanofiber anode material, it is characterised in that use electrostatic spinning Method prepare PVP/C₄H₆ZnO₄/C₁₀H₁₄O₅V composite nano fiber, obtains Zinc vanadate nanofiber negative pole through high-temperature calcination Material, specifically comprises the following steps that

(1) weigh a certain amount of PVP to be dissolved in ethanol, put into stirrer, regulate suitable rotating speed, under room temperature, stir 12～24 Hour to uniformly, stand de-bubble.

(2) a certain amount of vanadyl acetylacetonate (C is weighed₁₀H₁₄O₅And zinc acetate (C V)₄H₆ZnO₄·2H₂O) it is dissolved in DMF In, put into stirrer equally, regulate suitable rotating speed, stir 12～24 hours under room temperature to forming homogeneous solution.

(3) solution in step (2) is slowly poured in the solution of step (1), continue to be stirred at room temperature 5～6 hours to uniformly.

(4) solution in step (3) is carried out spinning in electrostatic spinning apparatus, obtain PVP/C₄H₆ZnO₄/C₁₀H₁₄O₅V Composite nano-fiber membrane, spinning voltage is 15～25kV, and receiving range is 10～20cm, and spinning speed is 0.3～1.0mL/h.

(5) composite nano-fiber membrane obtained in step (4) is put in tube furnace and calcine, from room temperature in air atmosphere To 500 DEG C, keeping temperature 3～5h, heating rate is 0.5～2 DEG C/min, and calcining is naturally cooling to room temperature after terminating.

The preparation method of a kind of lithium ion battery zinc ferrite nanofiber anode material the most according to claim 1, its feature exists In: the vanadic salts described in step (2) is vanadyl acetylacetonate；Zinc salt is zinc acetate.

The preparation method of a kind of lithium ion battery zinc ferrite nanofiber anode material the most according to claim 1, its feature exists In: prepared Zinc vanadate nanofiber is used for lithium ion battery negative material.