Electrochemical properties of lithium nickel oxide synthesized by the combustion method in an O2 stream

An appropriate mole ratio of urea/nitrate for preheating to synthesize LiNiO2 was examined by varying the ratio from 1.2 to 9.6. The chemical equation of the combustion reaction was deduced from the XRD analysis result of the mixture after preheating. The XRD pattern of the LiNiO2 sample calcined at 800 °C for 24 h, after preheating at the mole ratio of urea/nitrate of 3.6 at 400 °C, shows clear split of the 1 0 8 and 1 1 0 peaks, and the largest value of I003/I104. The sample calcined at 800 °C for 24 h has a relatively high first discharge capacity (164.2 mAh g−1) and a good cycling performance. Derivative −dx/|dV| vs. V curve of the LiNiO2 sample at the voltage range of 2.7–4.4 V for the first cycle exhibits four peaks for charging and discharging, showing that this sample goes through four phase transitions.