| Abstract: | Layered LiNi(1?x)/3Mn(1?x)/3Co(1?x)/3Crx]O2 materials with x = 0, 0.01, 0.02, 0.03, 0.05 are prepared by a solid-state pyrolysis method. The oxide compounds were calcined with various Cr-doped contents, which result in greater difference in morphological (shape, particle size and specific surface area) and the electrochemical (first charge profile, reversible capacity and rate capability) differences. The LiNi(1?x)/3Mn(1?x)/3Co(1?x)/3Crx]O2 powders were characterized by means of X-ray diffraction (XRD), charge/discharge cycling, cyclic voltammetry, and SEM. XRD experiment revealed that the LiNi(1?x)/3Mn(1?x)/3Co(1?x)/3Crx]O2 (x = 0, 0.01, 0.02, 0.03, 0.05) were crystallized to well layered  -NaFeO2 structure. The first specific discharge capacity and coulombic efficiency of the electrode of Cr-doped materials were higher than that of pristine material. When x = 0.02, the sample showed the highest first discharge capacity of 241.9 mAh g?1 at a current density of 30 mA g?1 in the voltage range 2.3–4.6 V, and the Cr-doped samples exhibited higher discharge capacity and better cycleability under medium and high current densities at room temperature. |
