Synthesis of LiNi1/3Co1/3Al1/3O2 cathode material with eutectic molten salt LiOH-LiNO3

Abstract

A lithium-ion battery cathode material, LiNi1/3Co1/3Al1/3O2, with excellent electrochemical properties was prepared by three-phase temperature sintering, using eutectic lithium salts (0.38LiOH.H2O-0.62LiNO3) mixed with the precursor Ni1/3Co1/3Al1/3(OH)2. This method was simple and inexpensive, and the materials could be mixed uniformly at the eutectic melting point without any grinding. A well-layered α-NaFeO2 structure was confirmed by X-ray diffraction (XRD). The ratio of characteristic diffraction peaks I(003)/I(104) reached 1.73. Charge–discharge testing of the synthesized powder showed an initial charge–discharge capacity of 151.5mAh.g–1 at a specific current of 0.2C in the range 2.8–4.3V up to 20 cycles with no noticeable capacity-fading (94.5% of the first discharge capacity), and reversible capacities of 133.7 and 120.9mAh.g–1 for specific currents of 1C and 2C at room temperature. The discharge capacity and capacity retention at 55°C were substantially better than at room temperature.