A new high-performance O3-NaNi0.3Fe0.2Mn0.5O2 cathode material for sodium-ion batteries

In recent years, sodium-ion batteries have received increasing attention as an alternative to lithium-ion batteries, and O3-type layered oxides are considered one of the candidates for commercial sodium-ion battery cathode materials. Here, we report a novel O3-NaNi0.3Fe0.2Mn0.5O2 sodium-ion battery cathode material, characterized by SEM, XRD, XPS, EIS, CV, and charge/discharge tests for the structural and electrochemical properties of O3-NaNi0.3Fe0.2Mn0.5O2. O3-NaNi0.3Fe0.2Mn0.5O2 has a discharge capacity of 139 mAh/g at 1 C and still has 77% capacity after 100 cycles, while it has a discharge capacity of 116 mAh/g at 5 C. The excellent cycling and rate performance is mainly due to the stability of the transition metal layer and the large spacing of the Na layer. These outstanding properties make O3-NaNi0.3Fe0.2Mn0.5O2 a potential candidate for sodium-ion battery cathode materials, and the experiments in this paper also provide suitable ideas for the discovery of new sodium-ion battery cathode materials.