Low temperature preparation of optimized phosphates for Li-battery applications

We describe the thermodynamics and kinetics that govern the precipitation of pure powders of phosphates phases of interest for Li-battery applications. We found precise procedures for the formation of three distinct crystalline forms of FePO4.2H(2)O and of pure LiMnPO4. Our attempts to precipitate either LiCoPO4 or LiFePO4, on the other hand, failed. In this latter case, optimized electrodes for battery applications were synthesized through a chemical conductive carbon coating at the surface of LiFePO4 prepared by evaporation of an Fe-III-containing aqueous solution. (C) 2004 Elsevier B.V. All rights reserved.