Effect of B-site substitution of (Li,La)TiO3 perovskites by di-, tri-, tetra- and hexavalent metal ions on the lithium ion conductivity

Abstract

Abstract. We report the synthesis and lithium ion conductivity of di-, tri-, tetra-and hexavalent metal ion B-site substituted (Li,La)TiO3 (LLT) perovskites. All 5-10 mol% Mg, A1, Mn, Ge, Ru and W ion substituted LLTs crystallize in a simple cubic or tetragonal perovskite structure. Among the oxides investigated, the Al-substituted perovskite La0.55Li0.361"10.09Ti0.995A10.00503 (1"1 = vacancy) exhibits the highest lithium ion conductivity of 1.1 x 10 -3 S/cm at room temperature which is slightly higher than that of the undoped (Li,La)TiO3 perovskite (8.9 x 10 4 S/cm) at the same temperature. The lithium ion conductivity of substituted LLTs does not seem to depend on the concentration of the A-site ion vacancies and unit cell volume. The high ionic conductivity of A1-substituted LLT is attributed to the increase of the B(A1)-O bond and weakening of the A(Li,La)-O bond. The conductivity behavior of the doped LLT is being described on the basis of Gibbs free energy considerations.

Solid state lithium ion conductors: Design considerations by thermodynamic approach

“…16). The observed results clearly show that substitution of the less stable attraction and hence inhances the lithium ion conductivity [63].…”

Structure and lithium ionic conduction of B-site Al-ion substitution in La4/3-yLi3yTi2O6

“…Thangadurai et al reported that the Al-substitution of 0.5% for Ti 4+ exhibited slightly higher lithium ions conductivity than that of undoped material [17]. In this study, we are focusing on how the ionic conductivity depends on lattice parameter, bottleneck size, and the structure change by the B-site ion substitution in La4/3_yLi3yTi2_xA14x/306 (y = 0.21, x = 0 ~ 0.60).…”

Ceramic and polymeric solid electrolytes for lithium-ion batteries

“…5 [43,44,49,50]. Small amounts of aluminum replacing titanium have been shown to lead to high conductivity, but the addition of sodium, which is added to the A-site (i.e.…”