Substituted cobalt oxides, LiM0.05Co0.95O2 (M 5 Mg21, Al31, and Ti41), have been synthesized using solid-state technique and
their performance in a 2032-type lithium rechargeable coin cell is reported. The synthesized powders were structurally analyzed
using X-ray diffraction ~XRD! and the surface morphology evaluated with scanning electron microscopy. XRD patterns indicate
that single-phase materials were formed involving Al-doped LiCoO2 . Electrochemical studies were carried out in the voltage
range 3.5-4.5 V ~vs. Li metal! using 1 M LiPF6 in ethylene carbonate/dimethyl carbonate as electrolyte. The doping involving 5%
Mg resulted in a charge/discharge capacity of ;160 mAh/g at C/5 rate and remained stable even after 50 cycles. To the best of our
knowledge, this is the first time that such high stable capacities have been obtained involving doped LiCoO2 when cycled up to
4.5 V