A Novel Ni-rich O3-Na[Ni0.60Fe0.25Mn0.15]O2 Cathode for Na-ion Batteries

O3-type layered oxide materials are being considered as one of the most promising cathodes for Na-ion batteries owing to their higher capacity, however, they usually suffer from structural damage at the highly desodiated state. To achieve the stable/high-capacity O3-type Na-ion cathodes, a series of Ni-rich O3–Na[NixFeyMn1-x-y]O2 (x ​= ​0.6, 0.7 and 0.8) oxide cathodes were successfully prepared and the phase transitions at high voltage were...