Ni-Rich Layered Oxide Li1.05(Ni0.7Mn0.3)O2 as a Highly Reversible Cathode Material for Lithium-Ion Batteries

Ni-rich layer-structured Li 1.05 (Ni 0.7 Mn 0.3 )O 2 compounds were constructed from calcining nickel manganese hydroxides by a simple co-precipitation method. Ni-rich Li 1.05 (Ni 0.7 Mn 0.3 )O 2 showed a pure NaFeO 2 phase and uniform spherical particles. Li 1.05 (Ni 0.7 Mn 0.3 )O 2 cathode demonstrated high reversible capacity (more than 190 mAhg –1 ) and good cycling stability (more than 160 mAhg –1 at voltage cutoff of 4.2 V over 100 cycles). Furthermore, its high rate capability could be maintained with the capacity of ∼140 mAhg –1 at 5C. The improved cycling stability maybe resulted from low Li/Ni cation mixing and good structure stability in the voltage between 2.75 and 4.2 V.