Rhombohedral Li2.4Na0.6V2(PO4)3@C nanoplates as high-rate and long-life cathode materials for lithium-ion batteries

Rhombohedral Li2.4Na0.6V2(PO4)(3)@C nanoplates are synthesized by a simple sol-gel method. The almost single rhombohedral phase nature of Li2.4Na0.6V2(PO4)(3)@C along with nanoplate structure leads to high specific capacity and rate capability, and a remarkable cycling performance. As cathode materials for lithium-ion batteries, rhombohedral Li2.4Na0.6V2(PO4)(3)@C nanoplates deliver a high initial discharge capacity of 121.6 mAh g(-1) and an excellent capacity retention of 95.6% after 200 cycles at a rate of 1 C in a potential range of 3.0-4.3 V. Even at a high rate of 10 C, an initial discharge capacity of 115.3 mAh g(-1) and a capacity retention of 76.7% after 500 cycles are observed. The outstanding electrochemical performance is attributed to the synergetic effect of stable rhombohedral phase, nanoplate structure and uniform carbon coating layer.