Synthesis of Nano-structured Li[NixCo1-2xMnx]O2-xFx via a Modified Carbonate Process

초록

Layered Li[Ni0.43Co0.22Mn0.35]O2-yFy (y = 0, 0.08) materials have been synthesized by a carbonate co-precipitation method. The structure, morphology, electrochemical properties, and thermal stability of the Li[Ni0.43Co0.22Mn0.35]O2-yFy have been studied. Spherical morphology and mono dispersed (approximately 15㎛) powders were obtained by well controlled carbonate process. XPS analysis clearly showed that fluorine ions successfully substituted for oxygen sites and the concentration of the fluorine ions decreased along with bulk direction. Li[Ni0.43Co0.22Mn0.35]O1.92F0.08 showed more stable cycling performance, enhanced thermal stability, and better high rate capability than bare Li[Ni0.43Co0.22Mn0.35]O2. The nano-structure morphology would also increase the contact surface between the electrolyte and electrode, enhancing the cell performance. Hence, our nano-structured morphology not only improves the structural stability of the electrode, but it is also expected to improve the overall performance of the Li-battery.