Cr-Doped Li₂ZnTi₃O₈ as a High Performance Anode Material for Lithium-Ion Batteries

Li₂ZnTi_2.9Cr_0.1O₈ and Li₂ZnTi₃O₈ were synthesized by the liquid phase method and then studied comparatively using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), galvanostatic charge-discharge testing, cyclic stability testing, rate performance testing, and electrochemical impedance spectroscopy (EIS). The results showed that Cr-doped Li₂ZnTi₃O₈ exhibited much improved cycle performance and rate performance compared with Li₂ZnTi₃O₈. Li₂ZnTi_2.9Cr_0.1O₈ exhibited a discharge ability of 156.7 and 107.5 mA h g^-1 at current densities of 2 and 5 A g^-1, respectively. In addition, even at a current density of 1 A g^-1, a reversible capacity of 162.2 mA h g^-1 was maintained after 200 cycles. The improved electrochemical properties of Li₂ZnTi_2.9Cr_0.1O₈ are due to its increased electrical conductivity.