Cathode materials prepared by a co-precipitation are 0.3Li2MnO3·0.7LiMn1−x Ni y Co0.1O2 (0.2≤ x ≤0.4) cathode materials with a layered-spinel structure. In the voltage range of 2.0–4.6V, the cathodes show more than one redox reaction peak during its cyclic voltammogram. The Li/0.3Li2MnO3·0.7LiMn1−x Ni y Co0.1O2 (x =0.3, y =0.2) cell shows the initial discharge capacity of about 200mAhg−1. However, when x =0.2 and y =0.1, the cell exhibits a rapid decrease in discharge capacity and poor cycle life.