Layered Lithium-Sodium Manganese Oxide As a Cathode Material for Lithium Ion Batteries

Lithium-Sodium Manganese Oxide, Na_x[Li_0.2Mn_0.8]O_1.6+δ( x = 0.4, 0.5, 0.6, 0.7, 0.8),were synthesized by solid-state reaction . The physical properties and electrochemical behaviors of Na_x[Li_0.2Mn_0.8]O_1.6+δ were characterized by X-ray diffraction, scanning electron microscope, and electrochemical measurement. XRD patterns show that when the x≥0.6, the samples exhibit symmetric hexagonal space group P63/mmc, with a P2 structure. It is found that Na_0.6[Li_0.2Mn_0.8]O_1.6+δ has the high discharge capacity and good cycle performance. At a discharge rate of 0.1C in the cut off voltage range of 2.0-4.8V, Na_0.6[Li_0.2Mn_0.8]O_1.6+δ gives an initial discharge capacity of 269mAh g^-1 and the capacity retention rate of 89% after 35 cycles.