| 摘要 |
The present invention provides a cathode active material, wherein the cathode active material has a uniform average particle diameter, thereby enabling to obtain high energy and high capacity properties and to improve the capacity properties, lifetime properties, and rate properties of a lithium secondary battery in a voltage area of 3-4.25 V. Also, the present invention provides a manufacturing method which adjusts pH and a reaction time according to a reaction progress in a reactor, thereby enabling to control the size of a particle of a generated lithium transition metal oxide such that a lithium nickel cobalt manganese-based cathode active material having a uniform size can be synthesized. To achieve the object of the present invention, the manufacturing method of the cathode active material precursor comprises the steps of: manufacturing a metallic aqueous solution including compounds represented by Chemical Formula 1 which is M_aA_bB_c, wherein M is Ni, Co, and Mn, A is at least one selected from a group consisting of Fe, Cr, Mg, Al, B, W, Ti, Zr, Cu, Zn, Yb, and Y, B is at least one selected from a group consisting of PO_4, BO_3, CO_3, F, and NO_3, and 0.95<=a<=0.1,0<=b<=0.03, and 0<=c<=0.02are satisfied; and putting a mixture of the metallic aqueous solution, a precipitating agent, and a co-precipitating agent, and making the mixture react while stirring the mixture so as to obtain a precipitate, wherein pH in the reactor represents different pH during mixing the precipitating agent and co-precipitating agent with the metallic aqueous solution from pH during reaching a steady state of the reaction in the reactor. |
