LiNiO2, LiNi0.995Al0.005O2, LiNi0.975Ga0.025O2, LiNi0.990Ti0.010O2 and LiNi0.990Al0.005Ti0.005O2 were synthesized by preheating at 400 A degrees C for 30 min in air and calcination at 750 A degrees C for 36 h in an O-2 stream with excess lithium amount z = 0.10 in Li1+z Ni1-y M (y) O-2. For these samples, the discharge capacities and discharge capacity degradation rate are compared. LiNiO2 has the largest discharge capacity at the 20th cycle (n = 20) and the 50th cycle (n = 50). LiNiO2 and LiNi0.995Al0.005O2 have relatively good cycling performances and their discharge capacities at n = 50 are 134 and 123 mAh/g, respectively, at 0.1 C rate. The crystallite sizes and strains were calculated by the Williamson-Hall method with XRD patterns and compared for the samples as prepared and after 50 charge-discharge cycles.