(1 – n – m)LiCo0.8Ni0.2O2 system was synthesized using the sol–gel method. Stoichiometric weights of the LiNO3, Mn(Ac)2 · 4H2O, Co(Ac)2 · 4H2O, Ni(NO3)2 · 6H2O for preparing of 28 samples have been used as starting materials of lithium, magnesium, cobalt and nickel, in 28 samples of (1 – n – m)LiCo0.8Ni0.2O2, respectively. We exhibited “Li1.333Ni0.4Co0.267Mn0.333O2” is the best composition for cathode material among those compositions. Obviously, the used weight of cobalt in this sample is lower compared with LiCoO2 that is an advantage in view point of cost and toxic problem. Charge–discharge characteristics of the mentioned cathode materials were investigated by performing cycle tests in the range of 2.2–4.5 V. Our results confirmed, although these kind systems can help for removing the disadvantage of cobalt which mainly is its cost and toxic, the performance of these kind systems are similar to LiCoO2 cathode material.