Li3Cr(MoO4)3: a NASICON-type high specific capacity cathode material for lithium ion batteries

摘要

Molybdate cathode materials have attracted a lot of attention due to their rich crystal structure, stable skeleton structure and moderate electronic conductivity. In this paper, a new NASICON-type material Li _(3) Cr(MoO _(4) ) _(3) has been studied for the first time as a cathode material for lithium ion batteries with high specific capacity. Comprehensive studies by X-ray diffraction, UV-vis-IR diffuse reflection, bond valence sum maps calculation, cyclic voltammetry, electrochemical impedance spectroscopy and the Four-Probe method show that Li _(3) Cr(MoO _(4) ) _(3) possesses a narrow band gap, high electronic conductivity and fast lithium ion transport channels, and delivers a high specific capacity (200 mA h g ~(?1) ) and rate performance. Electrochemical mechanism studies indicate that both the Mo ~(6+/5+) and Cr ~(3+) /Cr ~(2+) reactions contribute to the high specific capacity.