NaAlTi3O8, A novel anode material for sodium ion battery

Abstract

Sodium ion batteries are being considered as an alternative to lithium ion batteries in large-scale energy storage applications owing to the low cost. A novel titanate compound, NaAlTi3O8, was successfully synthesized and tested as a promising anode material for sodium ion batteries. Powder X-ray Diffraction (XRD) and refinement were used to analyze the crystal structure. Electrochemical cycling tests under a C/10 rate between 0.01 - 2.5 V showed that ~83 mAh/g capacity could be achieved in the second cycle, with ~75% of which retained after 100 cycles, which corresponds to 0.75 Na+ insertion and extraction. The influence of synthesis conditions on electrochemical performances was investigated and discussed. NaAlTi3O8 not only presents a new anode material with low average voltage of ~0.5V, but also provides a new type of intercalation anode with a crystal structure that differentiates from the anodes that have been reported.