Lithium chromium oxide modified spinel LiCrTiO4 with improved electrochemical properties

Abstract

Lithium chromium titanium oxide (LiCrTiO₄) spinel powders are synthesized by an acrylic acid polymerization method. The lithium intercalation capacity of the LiCrTiO₄ sample synthesized in air is about 150 mA h g⁻¹, which is very close to its theoretical capacity (157 mA h g⁻¹). In addition to its very good cycle performance similar to that of Li₄Ti₅O₁₂, the LiCrTiO₄ shows excellent rate performance with no obvious capacity loss at the current density from 1C to 10C rates. By means of Raman spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy, the LiCrTiO₄ sample synthesized in air is found to contain a small amount of lithium chromium oxide (LiCr_xO_y, y > 1/2 + 3x/2) as an in situ produced modifier that can improve the conductivity of the electrode.