| 摘要 |
PROBLEM TO BE SOLVED: To provide a process of producing a vanadium lithium phosphate carbon composite useful for a positive active material for lithium secondary batteries. SOLUTION: There is provided the process for producing the vanadium lithium phosphate carbon composite composed of a vanadium lithium phosphate having a NASICON structure and an electroconductive carbon material. The process comprises the first step to knead a concentrated phosphoric acid aqueous solution, a lithium source, a vanadium source, and an Me source added as necessary (Me donates a metal element or a transition metal element having an atomic number of not less than 11 except V) until the mixture becomes pasty, the second step to obtain a heat-treated product block by heat-treating the paste at a temperature of not lower than 100°C and lower than 700°C, the third step to prepare a slurry containing a pulverized heat-treated product and an electroconductive carbon material source by wet-pulverizing the pulverized heat-treated product and the electroconductive carbon material source with a media mill, the fourth step to obtain a pre-reaction precursor by spray-drying the slurry, and the fifth step to fire the pre-reaction precursor at a temperature of not lower than 700°C and not higher than 1,300°C in an inert gas environment or in a reducing environment. COPYRIGHT: (C)2012,JPO&INPIT |
