Abstract: The present invention relates to a positive electrode active material having improved capacity characteristic and life cycle characteristic, and a method of preparing the same, and specifically, to a positive electrode active material for a lithium secondary battery, wherein the positive electrode active material comprises a compound represented by Formula 1 above and allowing reversible intercalation/deintercalation of lithium, and from a crystal structure analysis of the positive electrode active material by a Rietveld method in which space group R-3m is used in a crystal structure model on the basis of an X-ray diffraction analysis, the thickness of MO slab is 2.1275 ? or less, the thickness of inter slab is 2.59 ? or greater, and the cation mixing ratio between Li and Ni is 0.5% or less, and a method of preparing the same.

Abstract: A solution supplying unit includes a body, a first supplying tube and a second supplying tube. The body includes a chamber having a substantially circular cross-section to receive a solution and an out-flowing part connected to the chamber to flow out the solution. The first supplying tube is disposed at a side of the body, tangentially connected to the chamber, and supplying a first solution into the chamber to rotate the first solution in the chamber. The second supplying tube has an end portion, and supplying a second solution into the chamber to mix the first solution with the second solution. The end portion is formed through the body and is adjacent to a central axis of the body.

Abstract: A solution supplying unit includes a body, a first supplying tube and a second supplying tube. The body includes a chamber having a substantially circular cross-section to receive a solution and an out-flowing part connected to the chamber to flow out the solution. The first supplying tube is disposed at a side of the body, tangentially connected to the chamber, and supplying a first solution into the chamber to rotate the first solution in the chamber. The second supplying tube has an end portion, and supplying a second solution into the chamber to mix the first solution with the second solution. The end portion is formed through the body and is adjacent to a central axis of the body.