A pseudoternary system Li2O-Cr2O3-TiO2 was investigated in the temperature range from 800 to 1100degreesC. A new compound with ramsdellite structure was discovered. The ramsdellite-type phase was obtained alone at temperatures above 1000degreesC in the composition range xless than or equal to1.5 of Li8/7(2-x/3)Cr8x/7Ti8/7(3-2x/3)O8. The ramsdellite structure showed reversible extraction and insertion cycles of lithium at the potential of ca. 4.0 V vs. Li/Li+ as well as 1.5 V. The former potential was attributed to a redox couple of Cr3+/Cr4+ and the latter to Ti3+/Ti4+. The crystal structure was maintained against the electrochemical extraction and insertion of lithium, and the cell volume was almost unchanged in the processes. (C) (2)002 The Electrochemical Society.