LiCu x II Cu y III Mn [ 2 − ( x + y ) ] III , IV O 4 : 5 V Cathode Materials

A series of spinels was prepared by solid‐state methods. Powder x‐ray diffraction analysis proved that the family assumes cubic spinel structures with a unit cell parameter slightly smaller than that of . Cyclic voltammetry and chronopotentiostatic techniques revealed that these materials exhibited two discharge regimes, at 4.1 and 4.9 V vs. the couple. The discharge capacity of was 71 mAh/g (97% of theoretical), with surprisingly good stability on cycling.