Ultra-high capacity of Li1.6−xMn0.4TixO2 as a cathode material

Cation-Disordered Li-Excess cathode material with an initial capacity over 300 mAh/g have drawn great attention as cathode materials for lithium batteries. In this work, Li1.3Mn0.4Ti0.3O2 cathode material with superior capacity was synthesized through the effective content adjustment of Li and Ti by ball milling combined with a high-temperature solid-state method. The synthesized Li1.3Mn0.4Ti0.3O2 possessed high crystallinity with a uniform particle size. The initial capacity reached 334.9, 230.5 and 127.3 mAh/g at current densities of 10, 50, and 100 mA/g, respectively. The oxidation-reduction of Mn3+/Mn4+, Mn2+/Mn3+ and O2-/O-, contributed to the ultrahigh capacity of Li1.3Mn0.4Ti0.3O2 was investigated by electrochemical characterization. The density of states in Li1.3Mn0.4Ti0.3O2 was studied by density functional theory based calculations. The experimental results show that Li1.3Mn0.4Ti0.3O2 could be promising cathode material for high-energy-density lithium batteries. •Li1.3Mn0.4Ti0.3O2 cathode material with superior capacity was synthesized through easy method.•The initial capacity reached 334.9 mAh/g at current densities of 10 mA/g at room temperature.•The oxidation-reduction of Mn3+/Mn4+, Mn2+/Mn3+ and O2-/O-, contributed to the ultrahigh capacity of Li1.3Mn0.4Ti0.3O2 was investigated by electrochemical characterization.•The Mn-O hybridization states dominated the electronic states in the vicinity of the Fermi level.