PREPARATION OF VOPO4.2H2O BY ULTRASONIC METHOD AND USE FOR CATHODE MATERIAL FOR LITHIUM SECONDARY BATTERIES

摘要

PURPOSE: A preparation method of VOPO4.2H2O used as a cathode material for lithium secondary batteries by ultrasonication is provided, which offers much shortened reaction time and fined particles compared with conventional method. CONSTITUTION: The preparation method of VOPO4.2H2O comprises the steps of: mixing V2O5, H3PO4 and H2O in a molar ratio of 1 : 40-50 : 500-610; ultrasonicating the mixture in a strength of 70-100W/cm¬2 for 10-15min; washing and decompression filtering; drying at room temperature. The resultant VOPO4.2H2O has 1-3micrometer size, 3.6V voltage and 135mAh/g discharge capacity. Also, the composition for a cathode material for lithium secondary batteries is prepared by mixing VOPO4.2H2O, acetylene black and polyethylene tetrachloride in a weight ratio of 60-80 : 15-25 : 5-15.