LITHIUM TRANSITION-METAL PHOSPHATE POWDER FOR RECHARGEABLE BATTERIES

摘要

The invention concerns the manufacture and use of phosphates of transition metals as positive electrodes for secondary lithium batteries and discloses a process for the production of LiMPO4 with controlled size and morphology, M being FexCoyNizMnw, with O , Fe<3+> and PO4<3->, - evaporating the water from the solution, thereby producing a solid mixture, - decomposing the solid mixture at a temperature below 500 DEG C to form a pure homogeneous Li and Fe phosphate precursor, and - annealing the precursor at a temperature of less than 800 DEG C in a reducing atmosphere, thereby forming a LiFePO4 powder. The obtained powders have a particle size of less than 1 mu m, and provide superior electrochemical performances once mixed for an appropriate time with electrical conductive powder.