PRECURSOR OF POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY AND MANUFACTURING METHOD THEREOF, POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM SECONDARY BATTERY USING THE PRECURSOR AND MANUFACTURING METHOD THEREOF, AND LITHIUM SECONDARY BATTERY USING THE POSITIVE ELECTRODE ACTIVE MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide an olivine-type positive electrode active material for a lithium secondary battery which has a fine grain size and exhibits excellent battery characteristics when being used as a positive electrode active material, to provide a method for manufacturing the positive electrode active material for a lithium secondary battery by using a precursor which is fine and uniform in composition, and to provide a lithium secondary battery with good characteristics by using the positive electrode active material.SOLUTION: There are provided a method for manufacturing a precursor of a positive electrode active material for a lithium secondary battery, the precursor, a method for manufacturing a positive electrode active material, the positive electrode active material and a lithium ion secondary battery. The positive electrode active material precursor for a lithium secondary battery comprises a phosphoric acid ammonium transition metal represented by the general formula: NHMPOnHO, where M represents one or more elements including at least Co selected from a group consisting of Fe, Mn, Ni and Co, and 0≤n≤1. The method for manufacturing the positive-electrode active material precursor comprises: a mixed solution-preparing step for preparing a mixed solution of a divalent M ions and phosphorus oxide ions; and a crystallization step for producing a phosphoric acid ammonium M salt by causing coprecipitation while adjusting the pH of the mixed solution to within the range of 7 to 9 by adding ammonia to the mixed solution.