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

Abstract

Carbon‐encapsulated Li3VO4 is synthesized by a facile environmentally benign solid‐state method with organic metallic precursor VO(C5H7O2)2 being chosen as both V and carbon sources yielding a core–shell nanostructure with lithium introduced in the subsequent annealing process. The Li3VO4 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 Li3VO4 composite with oxygen vacancies in Li3VO4, 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 Li3VO4 particle growth during the calcination process. The encouraging results demonstrate the significant potential of carbon encapsulated Li3VO4 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.

High capacity and superlong cycle life of Li3VO4/N–C hybrids as anode for high performance Li-ion batteries

“…1(b) is the Raman spectrum of the products. Apart from typical Raman peak of Li 3 VO 4 in wavelength region 150e1000 cm À1 [5,8,10,12,14], two strong peaks near 1340 and 1598 cm À1 can ascribe to disorder phase (D-band) and graphite phase (G-band) of carbon [5,8,10,14,16]. The results indicate Li 3 VO 4 /C composite is successfully prepared.…”

“…For the first aspect, it is found that solution based methods are more facile to obtain Li 3 VO 4 particles with smaller size compared with solid state reaction method [1,2,4,7,13]. For the second aspect, hybridizing Li 3 VO 4 with carbonaceous materials such as amorphous carbon, graphene, carbon nanotubes and graphite are demonstrated to be effective ways to improve the electronic conductivity of Li 3 VO 4 [3,5e10], and the hybridization degree between Li 3 VO 4 and carbon has crucial effect on the electrochemical performance of the Li 3 VO 4 / C. It is found that amorphous carbon derived from the carbonization of organics shows good combination with Li 3 VO 4 at nano-scale [3,6,12,14]. Besides, N-doping in such sort of carbon can be easily achieved [15e17], which is beneficial to improve the specific capacity and electronic conductivity of C [18,19].…”

Flow Battery Molecular Reactant Stability Determined by Symmetric Cell Cycling Methods

“…13 It is also possible to use low current density (e.g., C/20) cycling to access the entire capacity of the cell with minimal effect from polarization. [30][31][32][33] This method works for solid electrode single electrolyte systems such as lithium ion cells but is not as useful for flow cell characterization. Due to the presence of hydraulically-induced and other sources of noise in flow cells, performing a low current density capacity test over 20 hours is not the most time-efficient way for accurately determining capacity fade trends.…”

Self-template synthesis of hollow shell-controlled Li3VO4as a high-performance anode for lithium-ion batteries

“…S1 †). 13 For LVO, it is built up of oxy gen atoms in approximately hexagonal clos e packing and the cations occupy ordered t etrahedral s ites . 5 The large number of oxy gen vacancies leads to t he higher solubility of LVO-EG in w ater than t hat of LVO-H. Bas e on above res ults, we first designed the LVO -EG/LVO-H core-shell structure in the mixed solvent (denoted as LVO-M ), and then removed the LVO-EG core to form t he LVO hollow shell.…”