New layered metal oxides as positive electrode materials for room-temperature sodium-ion batteries |
(a) The typical first galvanostatic charge and discharge profiles of the Na0.9Cu1/4Fe1/4Mn1/4Ti1/4O2 electrode cycled between 2.5 V and 4.0 V at a current rate of C/10. (b) Cycle performance of the Na0.9Cu1/4Fe1/4Mn1/4Ti1/4O2 electrode cycled between 2.5 V and 4.0 V at a current rate of 1C. |