The novel porous double-shelled SnO2 @ C hollow spheres possess numerous outstanding properties. Its inner active hollow spheres can effectively improve the tag energy density and its double-shelled carbon wrapping outside of each SnO2-shell can protect the integrity of structure as well as enhance electrical conductivity. This is a significant improvement in the design and synthesis of multi-shell or core-shell functional materials. More valuably, the porous hollow structure can not only facilitate liquid electrolyte fast diffusion into the double-shelled spheres but also buffer large volume changes during lithium ions insertion/extraction. Importantly, due to the prominent dispersibility and high specific surface area, the SnO2 spheres can provide sufficient contact areas between active materials and electrolyte so as to improve its electrochemical performance. As a result, the obtained double-shelled SnO2 nanocomposites exhibit excellent rate capability, enhanced cyclability (911 mA h g (1) after 100 circles) and high specific energy density. Undoubtedly, the unique structure can provide a reference to effectively utilize hollow structures. (C) 2016 Elsevier Ltd. All rights reserved.