Comparative Study of Different Alkali (Na, Li) Titanate Substrates as Active Materials for Anodes of Lithium - Ion Batteries

Abstract

The relationship between structure and lithium storage capacity of different titanate samples as anode materials for lithium-ion batteries is discussed. Li 4 Ti 5 O 12 , Na 2 Ti 3 O 7 and Na 2 Ti 6 O 13 were synthesized by solid-state reaction. The structure, surface and morphology of the samples were characterized by SEM, XRD and RAMAN spectroscopy. The electrochemical performance was studied by galvanostatic charge-discharge cycling, cyclic voltammetry, electrochemical impedance spectroscopy and rate capability. The lithium titanate presented the highest capacity of the three electrodes, together with the most reversible potential plateau at 1.6 V vs. Li + /Li 0 and the best response in rate capability. Apparent diffusion coefficients of Li + ions into the titanate matrices were obtained, showing the highest value for the lithium titanate compound. Between both sodium titanates, Na 2 Ti 6 O 13 presented the highest specific capacity and the best discharge retention