A new approach was designed to synthesize tin-nanoparticles encapsulated in elastic hollow carbon spheres (TNHCs) with uniform size. Tin nanoparticles with a diameter <100 nm were encapsulated in one thin hollow carbon sphere. The content of tin is up to > 70% by weight, and the void volume inside the TNHCs is as high as 70-80%, which can accommodate the volume after expansion. This tin-based nanocomposite exhibits great potential as an anode material for lithium-ion batteries.