Microemulsion preparation and electrochemical characteristics of LiNi1/3Co1/3Mn1/3O2 powders
By Lu, Chung-Hsin & Lin, Yu-Kai
Published in Journal of Power Sources
2009
Abstract
Layer-structured LiNi1/3Co1/3Mn1/3O2 was successfully synthesized via a reverse microemulsion (RμE) route. Well-crystallized nanosized (around 45 nm) powders were obtained with calcination at 800 °C. The Rietveld refinement data revealed low degree of cationic displacement in the obtained powders. Within the voltage range of 2.5–4.5 V, the microemulsion-derived LiNi1/3Co1/3Mn1/3O2 delivered 187.2 and 195.5 mAh g-1 at room temperature and 55 °C, respectively. The prepared powders were found to exhibit low irreversible capacity and good capacity retention. Microemulsion-derived LiNi1/3Co1/3Mn1/3O2 demonstrated better rate capability than the solid-state derived samples, owing to the reduced particle size and increased surface area. Once the upper cut-off voltage reached 4.6 V, the capacity faded more rapidly than in other operation potential ranges. In this study, the microemulsion process effectively improved the electrochemical characteristics of LiNi1/3Co1/3Mn1/3O2. This soft chemical route possesses a great potential for synthesizing other types of cathode materials with multiple cations.