CN-122025576-A - Preparation method of lithium ion battery anode material

Abstract

The invention discloses a preparation method of a lithium ion battery anode material. The method comprises the steps of mixing graphite and cobalt acetylacetonate (1-2) according to the mass ratio of (1-7), grinding for 10-20 min to obtain a mixture, and calcining the mixture at 500-700 ℃ for 1-3 h in an air atmosphere to obtain a product containing graphite and cobaltosic oxide, namely the lithium ion battery anode material. The method does not need inert atmosphere protection, has simple process and low cost, and is suitable for industrial production. The prepared cathode material has the specific capacity of 1.6-2.2 times of that of commercial graphite after first discharge under 0.2A g ‑1 , has the capacity retention rate of 1.6-2.5 times of that of commercial graphite after 500 circles of circulation under 10A g ‑1 high current density, shows excellent high-rate long-cycle performance, and has application prospects in the fields of power batteries, high-power batteries and the like.

Inventors

• DING KEQIANG
• ZHAO QIAN
• ZHAO MIAN
• WANG HUI
• BAO JIAWEN
• CHEN YIQING
• NIU MENGQING
• Shi Wanting

Assignees

• 河北师范大学

Dates

Publication Date

20260512

Application Date

20260327

Claims (4)

1. 1. The preparation method of the lithium ion battery anode material is characterized by comprising the following steps: (1) Preparation of materials Graphite, cobalt acetylacetonate, acetylene black, polyvinylidene fluoride, N-methyl pyrrolidone, celgard2400 microporous polypropylene film, CR2430 type button cell casing; (2) Preparation of the Material And (3) respectively weighing graphite and Co (acac) 2 according to the mass ratio of (1-2), mixing the graphite and the Co (acac) 2 , fully grinding the mixture in an agate mortar for 10-20 min to obtain a mixture, and then placing the mixture in a muffle furnace to calcine the mixture at 500-700 ℃ in an air atmosphere for 1-3 h to obtain a product containing graphite and cobaltosic oxide, namely the lithium ion battery anode material.
2. 2. The method according to claim 1, wherein the mass ratio of graphite to cobalt acetylacetonate in step (2) is 1:3.
3. 3. The process according to claim 1, wherein the calcination temperature of the mixture of graphite and cobalt acetylacetonate in step (2) in the muffle furnace is 600 ℃.
4. 4. The process of claim 1, wherein the calcination time of the mixture of graphite and cobalt acetylacetonate in step (2) in the muffle furnace is 2 h.

Description

Preparation method of lithium ion battery anode material Technical Field The invention relates to a preparation method of a lithium ion battery material, in particular to a preparation method of a lithium ion battery negative electrode material, and belongs to the technical field of energy materials. Background Since the 21 st century, lithium ion batteries have been widely used in the fields of electronic products, electric vehicles, energy storage systems, aerospace and the like because of their high voltage, high energy density, long cycle life, no memory effect, environmental friendliness and the like. The lithium ion battery generally comprises a positive electrode, a negative electrode, an electrolyte, a separator and the like. The cathode material is used as one of the core components of the lithium ion battery, and directly influences the exertion of the overall performance of the lithium ion battery. Currently, the commercial lithium ion battery negative electrode materials are mainly lithium titanate and graphite. The graphite has the advantages of abundant resources, low cost, mature preparation process, high safety and the like, and has the advantages of high conductivity, large reversible specific capacity, stable charge and discharge platform, high energy density, high power density, good cycling stability and the like in the aspect of electrochemical performance. Thus, graphite anodes have taken up about 98% of the market share since lithium ion batteries were commercialized. Along with the deep research, the graphite cathode is found to have fast capacity attenuation and poor cycle stability under high current density, and the theoretical specific capacity of the graphite cathode is generally 372 mAh g-1, so that the graphite cathode is difficult to meet the requirements of high-energy-density batteries used in the fields of electric automobiles, unmanned aerial vehicles, robots and the like. Meanwhile, when the lithium ion battery is overcharged, lithium dendrites are precipitated on the surface of the graphite cathode material, and the precipitated lithium dendrites possibly puncture a diaphragm under specific conditions to cause short circuit, so that potential safety hazards are caused. Therefore, the advantages of the graphite anode material are exerted, the performance of the graphite anode material is improved, and the graphite anode material becomes a hot spot and difficult problem in the research field of the lithium ion battery at present. Literature investigation shows that the current method for modifying graphite mainly comprises the following steps of modifying the surface of graphite and regulating the morphology. Namely, the electrochemical performance of the graphite is improved by changing the surface property and morphology of the graphite. For example, jiele et al (CN 113394402A) discloses a preparation method of a spherical graphite cathode material with controllable morphology, which comprises the steps of firstly bonding graphite sheets into spherical particles, then coating a single-layer reticular metal copper on the outer layer, and uniformly coating a conductive agent on the surface and the inside of the particles. Chen Xinjiang et al (CN 112952070 a) discloses a method for preparing spherical porous graphite anode material, which comprises the steps of spheroidization of natural graphite, heat treatment of metal compound, coating of shell and the like. And secondly, surface coating and compounding. Namely, the purpose of improving the electrochemical performance of the graphite is achieved through the compounding of carbon coating and metal oxide. For example, poplar et al (CN 119601632A) discloses a modified microcrystalline graphite negative electrode material with composite and cladding, which is compounded with Fe3O4 and also clad with carbon, so that the structural stability and comprehensive lithium storage performance of the graphite negative electrode are improved to a certain extent. Lv Dongsheng et al (CN 108305994A) disclose a novel negative electrode material of graphite coated with aluminum phosphate coating on the surface, and the inventors believe that the aluminum phosphate protective layer can avoid direct contact of electrolyte and graphite, which is the main reason for improving the cycle stability and electrochemical performance of the battery. And thirdly, doping elements. I.e., a method of doping different elements into graphite to enhance the electrochemical properties of the graphite. For example, gu Yu et al (CN 119191272A) discloses a preparation method of a novel negative electrode material with resin foam as a framework and loaded with tungsten phosphosulfide, and the negative electrode material shows good cycle stability and safety. Li Zaijun et al (CN 104882608 a) disclose a method for preparing an N-doped three-dimensional graphene/graphite composite anode material, and the inventors of the patent believe that N doping can enhance el