Ternary lithium molybdenum oxide, Li2Mo4O13: A new potential anode material for high-performance rechargeable lithium-ion batteries

Abstract

The need to identify lithium ion battery anodes consisting of new materials that display high energy density and good cycling stability has interested the research on reversible so-called conversion reaction between lithium and molybdenum oxides such as ternary metal oxide (Li2Mo4O13). Polycrystalline Li2Mo4O13 was synthesized by conventional solid-state reaction route and explored as new potential anode material for secondary lithium ion battery applications vs. Li+/Li in half-cell mode. The electrochemical performance of the Li2Mo4O13 electrode was studied by cyclic voltammograms and galvanostatic discharge-charge cycling under different rates. In the working voltage between 2.5 V and 0.1 V, Li2Mo4O13 shows a high first charge capacity of 1062 mAh g−1 at current rate of C/10 (24 Li react with 10 h) and a superior rate capability with capacity retention of 1008, 842, 713 and 640 mAh g−1 under current rates of C/10, C/5, C/3 and C/2 (24Li react with in 2 h), respectively. Further, the cycling performance was evaluated at C/3 rate (424 mA g−1) and after 100 cycles a reversible capacity of 550 mAh g−1 was obtained with columbic efficiency of ∼100%. Ex-situ XRD studies confirmed that the electrochemical reaction involves insertion of 5Li/f.u vs. Li+/Li during discharge to 1.3 V and the crystal structure was retained when charged to 2.5 V. Below 0.8 V, conversion reaction occurs leading to amorphization of the phase. When discharged to 0.1 V, Mo+6 is reduced to Mo0 state on the basis of the conversion reaction.