A promising active anode material of Li-ion battery for hybrid electric vehicle use

In an attempt to respond to the requirement to provide promising anode material of Li-ion battery for hybrid electric vehicle (HEV) we examined mesophase-pitch-based cokes. The coke was heat treated at several temperatures where turbostratic structure is formed. Cyclic voltammograms (CV) were measured in 1:2 (v/v) mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) containing 1 M LiClO4 for all the samples, and the peak height was plotted against the square root of the potential scanning rate. The slopes of the plotting differed depending on the heating temperature and 1800 degrees C heated sample gave the steepest slope implying the diffusion coefficient of Li is the highest. For activating the electrochemical reaction site of the prepared electrode we adopted a novel method to expose the coated electrode in the glow discharge field in the presence of small amount of oxygen. As the result the CV peak height was increased by about two times as compared with that before the treatment. (c) 2008 Elsevier BY. All rights reserved.