CN-116779856-B - Lithium battery negative electrode material Mo2C/NiO@GO carbon nanofiber and preparation method thereof

Abstract

The invention discloses a preparation method of a lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber, which comprises the following steps of S1, weighing nickel oxide, ammonium molybdate tetrahydrate and a solvent, carrying out ultrasonic treatment, S2, weighing a high molecular surfactant, adding the high molecular surfactant into a beaker, stirring at normal temperature to obtain a required spinning solution, S3, sucking the spinning solution by a needle tube, carrying out electrostatic spinning to obtain a precursor, taking the precursor out of the drying oven after spinning is finished, S4, presintering the dried precursor, S5, carrying out suction filtration on the presintered precursor, and carrying out heat treatment on the precursor after suction filtration and drying to obtain the required lithium battery anode material. According to the preparation method, the Mo 2 C/NiO@GO material with the three-dimensional network structure is obtained, the specific surface area and the conductivity of the cathode material are improved, and the obtained battery has higher specific capacity and good cycling stability and has remarkable economic value.

Inventors

• WEI ZHENGANG
• XIAO BIN
• WU GANG
• XIE ZELIN
• WU YAJUAN
• GUAN CHUNYANG
• QIAO SHUAISHUAI

Assignees

• 江苏集芯半导体硅材料研究院有限公司
• 中国矿业大学

Dates

Publication Date

20260508

Application Date

20220311

Claims (6)

1. 1. The preparation method of the lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber is characterized by comprising the following steps of: S1, weighing nickel oxide, ammonium molybdate tetrahydrate and a solvent, sequentially adding the nickel oxide, the ammonium molybdate tetrahydrate and the solvent into a beaker, covering a preservative film, and performing ultrasonic treatment, wherein the ultrasonic power is 150-550W, and the ultrasonic time is 10-120min, and the molar ratio of the nickel oxide to the ammonium molybdate tetrahydrate to the solvent is 1:3-1:1; S2, weighing a high molecular surfactant, adding the high molecular surfactant into the beaker in the step S1, and stirring at normal temperature to obtain a required spinning solution, wherein the stirring speed is 100-600 r/min, and stirring for 8-24 h; S3, sucking the spinning solution by using a needle tube to perform electrostatic spinning to obtain a precursor, wherein the spinning voltage is 8-25V, the needle tube advancing speed is 0.2-1.0mL/h, the receiving distance is 13-20 cm, taking off the precursor after spinning is finished, and drying in an oven at the temperature of 60-90 ℃ for 6-24 h; S4, presintering the precursor dried in the step S3, wherein the presintering temperature is 200-250 ℃, the heat preservation time is 0.5-2 h, the heating speed is 0.5-5 ℃ per minute, and the atmosphere is air; s5, carrying out suction filtration on the precursor pre-sintered in the step S4, wherein the solvent is graphene oxide dispersion liquid, the concentration of the graphene dispersion liquid is 0.2-1 mg/mL, the suction filtration time is 3-60 min, and the pore diameter of a filter membrane is smaller than 1 mu m according to the selection of the corresponding membrane material of the solvent; S6, carrying out high-temperature heat treatment on the lithium ion battery anode material at 600-900 ℃, wherein the heat preservation time is 1-5 h, the temperature rising speed is 1-5 ℃ per minute, the atmosphere is inert atmosphere, and the required lithium ion battery anode material Mo 2 C/NiO@GO is obtained after the high-temperature heat treatment is finished.
2. 2. The preparation method of the lithium ion anode material Mo 2 C/NiO@GO carbon nanofiber, which is characterized in that in the step S1, one or more mixed solutions of N-Dimethylformamide (DMF), alcohol and dimethyl sulfoxide (DMSO) are selected as a solvent.
3. 3. The method for preparing the lithium ion anode material Mo 2 C/NiO@GO carbon nanofiber according to claim 1 or 2, wherein the high molecular surfactant in the step S2 is one of polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA) and Polyacrylonitrile (PAN).
4. 4. The preparation method of the lithium ion anode material Mo 2 C/NiO@GO carbon nanofiber according to claim 1 or 2, wherein the graphene dispersion liquid solvent in the step S5 is one or more mixed solutions of deionized water, N-Dimethylformamide (DMF) and alcohol.
5. 5. The method for preparing the lithium ion anode material Mo 2 C/NiO@GO carbon nanofiber according to claim 1 or 2, wherein the inert gas used for the high-temperature heat treatment in the step S6 is one or a mixture of argon and nitrogen.
6. 6. The lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber is characterized in that the lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber is prepared by the preparation method of the lithium ion anode material Mo 2 C/NiO@GO carbon nanofiber according to any one of claims 1-5.

Description

Lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber and preparation method thereof Technical Field The invention relates to a preparation method of a battery anode material, in particular to a lithium battery anode material Mo 2 C/NiO@GO carbon nanofiber and a preparation method thereof, and belongs to the fields of nano material synthesis and battery preparation. Background Lithium Ion Batteries (LIBs) are currently the most common secondary battery electrochemical energy storage systems, and are widely used in the fields of portable electronic mobile devices and new energy automobiles. The lithium ion battery mainly comprises a positive electrode, a negative electrode and a diaphragm, and the electrochemical performance of LIBs can be effectively improved by improving the structure and the performance of the negative electrode material. At present, the most widely used negative electrode material is graphite carbon, which has better stability, but poorer multiplying power performance and low theoretical specific capacity, namely 372mAhg -1. This severely restricts the electrochemical performance of LIBs, limiting the further development of LIBs, and thus the development of new generation lithium battery anode materials is urgent. The transition metal oxide represented by nickel oxide has very high theoretical specific capacity (718 mAhg -1), has very abundant reserves in the crust, is convenient for large-scale industrial use, has very great prospect and is a good negative electrode material in the future and is attracting great attention. However, the current application process is limited by the fact that the conductivity is too low, while the molybdenum-based carbide has not only high theoretical specific capacity (600 mAhg -1-1000mAhg-1) but also unusual conductivity (1.02X10 2 S/cm), and the conductivity of the nickel oxide-based anode material can be effectively improved by adding molybdenum doping on the basis of nickel oxide. In addition, in the charge and discharge process, the huge volume change of nickel oxide during the alloying/dealloying reaction can lead to the crushing of active material particles, so that rigid cracks of a solid-electrolyte interface are formed and active material powder is separated from a current collector, finally, the capacity of an electrode is reduced, and the service life of a battery is shortened. In order to improve the service cycle of the battery, the volume expansion of the nickel anode material in the lithium ion deintercalation process needs to be improved. Research has shown that designing a multi-element transition metal oxide into a hollow nanostructure is widely considered as an effective solution. By regulating the structure and the size of the material, the diffusion path of lithium ions can be shortened by a unique hollow nano structure, so that the serious volume expansion problem of the material in the process of lithium removal and lithium intercalation is effectively relieved, and the aim of improving the battery performance is fulfilled. In addition, 2D carbon material graphene formed by sp hybridization of C atoms has a specific surface area of 2630mg, and the graphene has high heat conductivity and mechanical strength. The graphene can be used as a good conductive additive and a heat conducting material, so that the overall conductivity of the material is further improved, the thermal diffusion of an electrode in the charge-discharge cycle process is facilitated, and secondly, the medium-two-dimensional nano structure of the graphene can be used as a natural conductor of an active material, and the unique mechanical property can be used for relieving the problem of volume change of the material, so that the aims of simultaneously improving the multiplying power and the cycle performance are fulfilled. Therefore, the Mo 2 C/NiO@GO carbon nanofiber is a composite anode material with great application prospect. At present, few research on Mo 2 C/NiO@GO composite materials is carried out, the application number is CN201510661685.9, the patent of a preparation method of a molybdenum oxide/nickel/carbon composite anode material of a lithium ion battery is introduced, the molybdenum oxide/nickel carbon composite anode material is synthesized by adopting a chemical vapor deposition method, the preparation method is simple and convenient, but the problem of poor cycling stability caused by volume change of metal oxide during alloying/dealloying reaction cannot be solved, but the production scale of the method is limited, and the consistency of a sample generated by water heat is poor. The application number is CN201910158517.6, the name of the preparation method of the nickel molybdate doped carbon quantum dot lithium ion battery anode material is that a simple method for preparing NiMoO 4 nano particles is introduced, but the problem of low cycle life of binary metal oxide due to lower conductivity and poorer lithium ion transmission kinetics