CRYSTALLINE IRON PHOSPHATE DOPED WITH METAL, METHOD OF PREPARING THE SAME, AND LITHIUM COMPOSITE METAL PHOSPHATE PREPARED THEREFROM

摘要

Provided are a crystalline iron phosphate doped with metals (MFePO4),which is used as a precursor of olivine-structured LiMFePO4 (LMFP) used as acathode active material for lithium secondary batteries, and a method ofpreparingthe crystalline iron phosphate, in which a crystalline iron phosphate dopedwithmetals has the following Formula I obtained by crystallizing amorphous ironphosphate and doping the latter with a different type of a metal. Formula I:MFePO4, where M is selected from the group consisting of Ni, Co, Mn, Cr, Zr,Nb,Cu, V, Ti, Zn, Al, Ga, Mg, and B. The preparation of olivine-structured LMFP,which is used as a cathode active material for lithium secondary batteries,using thecrystalline iron phosphate doped with metals as a precursor can increaseefficiencyand reduce processing costs as compared to another method of preparing thesame bymixing different types of metals in a solid state.