Progress of Anion Redox in Na-rich Layered Transition Metal Oxides (Na2MO3) as Cathode Materials for Sodium-ion Batteries

Under the background of surging global demand for batteries and scarcity of Li resources, sodium-ion batteries (SIBs) are attracting attention as a potential alternative with their unique advantages, and the layered transition metal oxides therein are considered to be one of the most promising cathode materials. In this paper, firstly, the diversity of cathode materials for sodium-ion batteries is systematically introduced, as well as the layered oxide structures among them are categorized, and then it focuses on the O3-type sodium-rich Na