A rationally designed 3D interconnected porous tin dioxide cube with reserved space for volume expansion as an advanced anode of lithium-ion batteries.

To work against the volume expansion (similar to 300%) of SnO(2)during lithiation, here a sub-micro sized, interconnected, and porous SnO(2)cube with rationally designed reserved space (similar to 375%) is synthesizedviaan artful topochemistry route (CaSn(OH)(6)-CaSnO3-SnO2). Owing to its microstructure, this novel material harvests enhanced lithium-storage performance.