Fast and Reversible Li Ion Insertion in Carbon‐Encapsulated Li₃VO₄ as Anode for Lithium‐Ion Battery

Carbon‐encapsulated Li 3 VO 4 is synthesized by a facile environmentally benign solid‐state method with organic metallic precursor VO(C 5 H 7 O 2 ) 2 being chosen as both V and carbon sources yielding a core–shell nanostructure with lithium introduced in the subsequent annealing process. The Li 3 VO 4 encapsulated with carbon presents exceeding rate capability (a reversible capability of 450, 340, 169, and 106 mAh g −1 at 0.1 C, 10 C, 50 C, and 80 C, respectively) and long cyclic performance (80% capacity retention after 2000 cycles at 10 C) as an anode in lithium‐ion batteries. The superior performance is derived from the structural features of the carbon‐encapsulated Li 3 VO 4 composite with oxygen vacancies in Li 3 VO 4 , which increase surface energy and could possibly serve as a nucleation center, thus facilitating phase transitions. The in situ generated carbon shell not only facilitates electron transport, but also suppresses Li 3 VO 4 particle growth during the calcination process. The encouraging results demonstrate the significant potential of carbon encapsulated Li 3 VO 4 for high power batteries. In addition, the simple generic synthesis method is applicable to the fabrication of a variety of electrode materials for batteries and supercapacitors with unique core–shell structure with mesoporous carbon shell.