Hollow-in-Hollow Carbon Spheres for Lithium-ion Batteries with Superior Capacity and Cyclic Performance

• Hollow-in-hollow structured HIHCS was synthesized via a facile templating strategy.
• The HCS core and hollow carbon shell constitute the hollow-in-hollow structure.
• The HIHCS exhibited superior rate capability and cycle stability as anode material.
• The excellent performance is attributed to the unique hollow-in-hollow structure.

Hollow spheres structured materials have been intensively pursued due to their unique properties for energy storage. In this paper, hollow-in-hollow carbon spheres (HIHCS) with a multi-shelled structure were successfully synthesized using a facile hard-templating procedure. When evaluated as anode material for lithium-ion batteries, the resultant HIHCS anode exhibited superior capacity and cycling stability than HCS. It could deliver reversible capacities of 937, 481, 401, 304 and 236 mAh g−1 at current densities of 0.1 A g−1, 1 A g−1, 2 A g−1, 5 A g−1 and 10 A g−1, respectively. And capacity fading is not apparent in 500 cycles at 5 A g−1. The excellent performance of the HIHCS anode is ascribed to its unique hollow-in-hollow structure and high specific surface area.