| abstract |
The present invention relates to a method for preparing a cathode active material precursor for a secondary battery by performing a coprecipitation reaction while injecting, into a batch type reactor, a transition metal-containing solution containing a transition metal cation, a basic solution and an ammonium solution, wherein the molar ratio of the ammonium ion included in the ammonium solution to the transition metal cation included in the transition metal-containing solution injected into the batch type reactor is 0.5 or less, and the pH inside the batch type reactor is maintained to be 11.2 or less. |