Patent ID: 8142750

Claim:
A method of manufacturing an active material, the method comprising: a hydrothermal synthesis step of heating a mixture including a lithium compound, a metal compound containing one species selected from the group consisting of Fe, Mn, Co, Ni, and V, a phosphorus compound, and water within a reactor while keeping an internal pressure of the reactor at 0.3 MPa or lower by ventilating the inside of the reactor to the outside of the reactor, and closing the reactor at a time when the temperature of the mixture reaches a temperature in the range of from 100 to 150° C. and continuing heating; a firing step of firing the mixture at a temperature in the range of from 400 to 700° C. after the hydrothermal synthesis step, wherein the active material comprises at least one phosphate selected from the group consisting of LiFePO 4 , LiMnPO 4 , LiCoPO 4 , LiNiPO 4 , and LiVOPO 4 .