METHOD FOR CONTINUOUS PREPARATION OF LITHIUM-CONTAINING PHOSPATE NANOPARTICELS FOR POSITIVE ACTIVE MATERIALS

摘要

PURPOSE: A successive manufacturing method of phosphate positive active material nanoparticles is provided to improve electrochemical features with an introduction of a metal dopant or a nonmetal dopant, and to control a formation of impurity with an introduction of a reducing agent. CONSTITUTION: The successive manufacturing method of phosphate positive active material nanoparticles includes following steps.(a) A lithium precursor solution, an iron precursor solution, a phosphoric acid precursor solution, a metal dopant or nonmetal dopant precursor solution and a reductant solution are prepared respectively.(b) The solutions of the step(a) are introduced consecutively to a mixer under a supercritical or subcritical condition. A solution containing 'phosphate positive active material nanoparticles' having a chemical formula of LiFe1-xMIxPO4 or Li1-xMIIxFePO4(0<=X<=0.3, MI andMII are a metal or a base metal) is formed.(c) The solution containing 'phosphate positive active material nanoparticles' is successively introduced to a reactor with high pressure and high temperature. The crystallinity of phosphate positive active material nanoparticles' is increased.(d) The solution containing 'phosphate positive active material nanoparticles' is cooled. (e) The phosphate positive active material nanoparticles are divided and collected.