Abstract
The electrochemical behavior of a new cobalt‐substituted 
(y = 4) spinel phase is studied in liquid‐electrolyte lithium cells. The insertion electrode material was obtained by reacting the mixed carbonate 
with LiOH at 380°C. The spinel phase with 
composition was obtained by this procedure. This material shows an extended cycle life in lithium‐anode cells working at room temperature in a 3.3 to 2.3 V potential window. Cell capacity is retained by 80% after 200 cycles.