Nanosized La2O3 powder prepared by the solid-state chemical reaction method was added to sublimed sulfur cathode to form a composite material for lithium-sulfur rechargeable batteries. Lithium-sulfur battery systems, in which sublimed sulfur cathodes with nanosized La2O3 powder were used, showed an improvement in cycle life and discharge capacity (compared to regular Li-S systems). From the results reported herein, it is confirmed that the addition of nanosized La2O3 powder to sublimed sulfur has a positive effect on polysulfides adsorption, and also has a catalytic effect that promotes the lithium-sulfur redox reaction. Furthermore, it was found that the presence of nanosized La2O3 in the composite sulfur cathodes increases their porosity, which has a positive effect on their kinetics. (c) 2006 The Electrochemical Society.