The Graphene-Based Comeposite Material For Application In The Negative Electrode Lithium-Ion Battery

In recent years, Lithium-ion batteries have been widely used in many fields as a new kind of clean energy, with small size, large capacity, no memory effect and so on. In this area, the lithium-ion battery power has become a hot point. Anode material is the key to improve the performance of lithium-ion battery. Graphene as a novel conductive material has been attracting people’s attention, with its admirable electrochemical performance. Graphene is a hexagonal crystal formed by SP2 hybridized carbon atoms. It is a kind of two-dimensional material with a thickness of the carbon atoms. Both large specific surface area and high chemical stability are the advantage of Graphene. At the same time, graphene has a strong lithium storage capacity for its large specific surface area, which increased the specific capacity of the lithium ion battery greatly. Graphene can be directly used as a negative electrode material for the lithium ion batteries, significantly higher the capacity and cycle stability of the batteries. Used as the substrate, graphene can be doped by transition metal oxide on the graphene sheet, which can obviously improve the electrochemical properties of the graphene. As a result, the specific capacity, cycle life, cycle stability and some other properties of the lithium ion battery can be further improved.The graphene was prepared by solvothermal method, and then the lithium nitride doped in the graphene as nitrogen and synthesized nitrogen-doped graphene in this article. Using chemical methods, Co3O4 and SnO2h nanoparticles were doped on graphene surface to prepare the graphene/Co3O4 composites and graphene/SnO2 composites. The prepared composite materials were used as the anode materials toimprove the performance of lithium-ion battery. The comparing charging and discharging tests and cyclic voltammetry tests of the obtained lithium ion batteries were performed at LAND battery test system (CA2001A) and electrochemical workstation (CHI760), respectively. The data was collected and analyzed. Improvements of the battery performance was observed when nitro,SnO2 nanoparticles and Co3O4 nanoparticles were doped.