| 초록 |
Sodium ion batteries have been considered as the most potential substitute for conventional Lithium ion batteries for the following reasons(1. high abundance and inexpensive for Na sources 2. Similarities to LIBs). Traditionally, a lot of research on transition metal for cathode have been investigated , however, This limits potential available capacities in battery performance. Recently it was found that oxygen can participate in the lithation/delithiation process and their oxidation states are changed between -2 and -1. In this study, P2-Na0.7Li0.23Mn0.77O2 cathode is doped with Ti to get high performance at high voltage. P2-Na0.7Li0.23Mn0.67Ti0.1O2 cathode facilitates Na+/vacancy disordering. This disordering reduces the overpotentials upon battery cycling. NLMTO shows capacities of 110 mAh g-1 nearly twice at a current density of 100 mA g-1 after 150 cycles compared with NLMO. Ti doping effects are better observed showing that even at high voltage range from 1.5 V – 4.6 V. |
