Study on the Synthesis by Milling and Solid-State Reaction Method and Electrochemical Properties of LiNiO2

LiNiO2 was synthesized by the solid-state method after mixing LiOH center dot H2O and Ni(OH)(2) with SPEX mill. The optimum condition for the synthesis of LiNiO2 was the calcination at 750 degrees C for 30 h in O-2 stream after milling for 1 h. The LiNiO2 synthesized under this condition showed relatively large value of I-003/I-104 and relatively small value of R -factor. When LiNiPO2 was cycled in 2.7 similar to 4.15 V at 0.1C -rate, the fi similar to 4.2 V at 0.1C -rate, the first discharge capacity was large but it showed poor cycling performance probably because of the transition of H-2 hexagonal structure to H-3 hexagonal structure. In addition, when LiNiO2 was cycled in 1.0 similar to 4.8 V at 1/24C-rate, the first discharge capacity was very large (257.7 mAh/g) and the discharge capacity increased with the number of cycles.