Preparation of Delithiated LixCoO2 as Cathode Material for High Power Densities Primary Lithium Batteries

The dethiliated LixCoO2 powder as cathode material for primary lithium batteries was prepared through a chemical delithiation reaction of LiCoO2 powder with sulfuric acid solution. By using atomic absorption spectroscopy and potentiometric titration, the chemical formula for the dethiliated LixCoO2 is determined to be Li0.33CoO2. XRD measurement reveals the lattice parameters of a = 2.8107 angstrom, c = 14.4252 angstrom, and V = 98.69 angstrom(3) based the hexagonal layered structure with R (3) over barm space group for the dethiliated LixCoO2 powder. The intensities of diffraction peaks of the dethiliated LixCoO2 powder are lower than those of LiCoO2 powder, and the c-axis is expanded upon the Li+ extraction from LiCoO2. SEM analysis discloses the smaller particles with more evenly distributed dimension for the dethiliated LixCoO2 powder. The galvanostatic discharge test shows that the Li/LixCoO2 cells using LiClO4 as electrolyte solution display excellent rate capability at different cutoff discharge voltages, where the capacities of 112.02 and 889.14 mAh g(-1) can be acquired at the high current rates of 180 mA g(-1) with the cutoff discharge voltage of 2.0 and 0.5 V, respectively. Moreover, the Li/LixCoO2 cells also exhibit good storage performance and accepted low temperature performance, indicating that the dethiliated LixCoO2 can be used a potential cathode material for high power densities primary lithium batteries.