Lithium chromium oxide modified spinel LiCrTiO4 with improved electrochemical properties

摘要

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 Li4TisO4, the LiCrTiO4 shows excellent rate performance with no obvious capacity loss at the current density from 1C to IOC 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.