Structural, Chemical, and Electrochemical Characterization of Layered Li[Li[sub 0.17]Mn[sub 0.33]Co[sub 0.5−y]Ni[sub y]]O[sub 2] Cathodes

Layered cathodes belonging to a solid solution series between layered and were synthesized at 900 and and characterized as cathode materials for lithium-ion batteries. The observed lithium content in the samples decreases with increasing Ni content due to a tendency to form and volatilization of lithium during synthesis. The first charge and discharge capacities decrease with increasing Ni content. For example, the first discharge capacity drops from for the sample to for the sample. The decrease in the discharge capacity with increasing Ni content is due to a decrease in the lithium content in the transition metal layer and a consequent decrease in the amount of oxygen lost irreversibly during the first charge as indicated by a structural and chemical characterization of the chemically delithiated samples.