Electrochemical intercalation activity of layered NaCrO2 vs. LiCrO2

Electrochemical activities of layered LiCrO2 (R-3m) and NaCrO2 (R-3m) materials were investigated at room temperature in aprotic organic electrolyte solutions. LiCrO2 and NaCrO2, possessing the same polytypism and the same transition metal atom, were inactive and active in 1 mol dm−3 LiClO4 and NaClO4 propylene carbonate, respectively. The NaCrO2 electrode performed the highly reversible capacities of ca. 120 mAh g−1 with satisfactory capacity retention in a Na cell.