Na‐Ion Batteries: Positive Electrode Materials

Abstract

The growing desire for large‐scale stationary electrical power storage is driving research interest into Na‐ion batteries, due to the greater abundance and lower cost of Na versus Li. This article focuses on advances achieved in the development of positive electrode (cathode) materials for such batteries. As for Li‐ion batteries, layered transition metal oxide systems have traditionally dominated the research in this area, although following the development of LiFePO 4 for Li‐ion batteries, there has been considerable interest in Na transition metal phosphate/sulfate/silicate systems among other materials.

Investigation into the ability of langbeinite-type K2M2(SO4)3 (M = Mn, Fe, Co and Ni) materials to accommodate Na: The importance of the electronegativity of the framework cation

“…Although the predominant technology currently used is the Li-ion battery, cost and sustainability have driven research to explore alternative systems, such as Na, which may be better suited for large scale storage due to sodium's high natural abundance and hence lower cost. [1][2][3] Three dimensional structures such as NaSICON and garnet have played an important role within the battery community due to a number of advantages such as favourable ionic conductivity and structural stability. NaSICON (Sodium (Na) Super Ionic Conductor) phases are a group of materials with the general formula AyMM′(XO4)3 (0≤y≤4) where A can either be an alkali, alkaline earth or rare earth cation (e.g.…”