An electrochemical study of lithium insertion into Cr5−yTiySe8 (y = 1, 2, 3, 4, 4.5) beyond the intercalation limit

We studied the electrochemical reaction of lithium with the pseudo-layered compounds Cr(5-y)Ti(y)Se(8) (y = 1, 2, 3, 4, 4.5). About 16 Li ions per formula unit can be inserted reversibly corresponding to a specific capacity of about 500 mAh g(-1). The electrical potential where the discharge process occurs is decreasing monotonically with increasing titanium content y. The voltage of the discharge process can be adjusted via the titanium content between 0.8 and 0.35 V.