Nano Carbon as the Anode of Li Ions Batteries

Abstract

Among the different kinds of electrochemical energy storage systems, lithium ions batteries (LIBs) have been one of the most promising. In LIBs, the charge/discharge is based on the mechanism of rocking chair in which Li ions shift back and forth easily between cathode and anode by crossing the electrolyte with a porous polymer separator. The cathodes are usually made with Li transition metal oxide, such as LiCoO2 and LiMn2O4 on Al foil. The electrolyte is composed by the organic liquids, such as PC, EC and DEC, with Li salts, such as LiPF6 and LiBF4. The anode can be Li metal on Cu foil with high theoretical capacity of 3860 mA h/g. However, the formation of Li dendrite on the Li metal surface results in the serious safety issues and cycle stability. The use of carbonaceous materials (introduced by Sony Corporation, 1991) in anode promotes obviously the solution of safety issues and results in the broad use of LIBs in modern life, especially in portable electronic devices, such as laptops, mobile phones, cardiac pacemakers, and so on [1].