| abstract |
The present invention provides a lithium cobalt composite oxide powder for a lithium secondary battery positive electrode having a large capacity density, high safety, and excellent charge / discharge cycle durability (capacity retention ratio), and a method for evaluating the same. A general formula Li p Co x M y O z F a ( where, M is a transition metal element or an alkaline earth metal element other than Co .0.9 ≦ p ≦ 1.1,0.980 ≦ x ≦ 1.000, 0 ≦ y ≦ 0.02, 1.9 ≦ z ≦ 2.1, x + y = 1, 0 ≦ a ≦ 0.02). for the positive electrode active material for the next cell, it detects the respective spectral absorption intensity around 1450 cm -1 vicinity and 1030 cm -1 in the diffusion reflection Fourier transform infrared spectrometer, whether the spectral absorption intensity ratio is within a predetermined range Evaluate by In particular, a lithium cobalt composite oxide powder having excellent characteristics can be obtained by setting each spectral absorption intensity ratio of 1450 cm −1 and 1030 cm − to 0.2 or less. [Selection figure] None |