A key technology to improve the cyclic performances of carbonaceous materials for lithium secondary battery anodes

摘要

Any carbonaceous material does not necessarily provide a favorable surface for a smooth electrochemical lithium doping/undoping reaction because the carbon surface is covered with a very thin inhibiting surface layer. Especially, carbonaceous materials prepared at lower temperatures exhibit very poor charge/discharge cycleability. Removing such a surface layer was found quite effective to provide very favorable electrode surfaces for the doping/undoping reaction. Simple heating of the pristine sample in vacuum was effective, but a more effective and versatile method was a mild oxidation treatment at a moderate temperature only for several minutes.