| abstract |
The present invention is a lithium-cobalt composite oxide for use in a positive electrode active substance for an electrochemical device, said lithium-cobalt composite oxide being characterized in that: fluorine ions eluted in an eluant in which the lithium-cobalt composite oxide is dispersed in ultrapure water are present in a range of 500-15,000 ppm by mass ratio with respect to the lithium-cobalt composite oxide; and the composition of the lithium-cobalt composite oxide is represented by formula (1), namely, Li 1-x Co 1-z M z O 2-a F a (-0.1≤x<1, 0≤z<1, 0≤a<2), wherein M represents at least one metal element selected from the group consisting of Mn, Ni, Fe, V, Cr, Al, Nb, Ti, Cu, and Zn. As a result, the present invention provides a lithium-cobalt composite oxide that makes it possible to obtain high charge/discharge capacity and high cycle characteristics when used as a positive electrode active substance for an electrochemical device. Also provided is a production method for the lithium-cobalt composite oxide. |