General strategy for designing core-shell nanostructured materials for high-power lithium ion batteries.

Because of its extreme safety and outstanding cycle life, Li(4)Ti(5)O(12) has been regarded as one of the most promising anode materials for next-generation high-power lithium-ion batteries. Nevertheless, Li(4)Ti(5)O(12) suffers from poor electronic conductivity. Here, we develop a novel strategy for the fabrication of Li(4)Ti(5)O(12)/carbon core-shell electrodes using metal oxyacetyl acetonate as titania and single-source carbon. Importantly, this novel approach is simple and general, with which we have successfully produce nanosized particles of an olivine-type LiMPO(4) (M = Fe, Mn, and Co) core with a uniform carbon shell, one of the leading cathode materials for lithium-ion batteries. Metal acetylacetonates first decompose with carbon coating the particles, which is followed by a solid state reaction in the limited reaction area inside the carbon shell to produce the LTO/C (LMPO(4)/C) core-shell nanostructure. The optimum design of the core-shell nanostructures permits fast kinetics for both transported Li(+) ions and electrons, enabling high-power performance.