Metal oxide composites for lithium-ion battery anodes synthesized by the partial reduction process

A thermochemical process based on the partial reduction of mixed oxides is used to create ultrafine metal-ceramic composites for Li-ion battery electrodes. Mixed oxides containing a more noble metal selected to be capable of alloying with lithium at potentials useful as a Li-ion battery anode are partially reduced to form electrochemically active metal-ceramic composites. Experiments show the differences in microstructure obtained in systems with slow oxygen diffusion (SbVO4, AgVO3, and Ag2V4O11), fast oxygen diffusion (Sb2Mn2O7 distorted fluorite), and microphase separation (Sn0.5Ti0.5O2 rutile). Materials are characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and scanning transmission electron microscopy, and electrochemical tests are presented. Reversible charge capacities of 200-350 mAh/g (1100-2200 mAh/cm(3)) have been obtained in experiments to date. (C) 2002 The Electrochemical Society.