Design and preparation of interconnected quasi-ball-in-ball tin dioxide/carbon composite containing void-space with high lithium storage properties

Rapid capacity fading is one of the major obstacles that seriously impede the applications of tin dioxide (SnO2)-based electrodes. Compositing SnO2 with carbon to form SnO2/carbon composites with rational nanostructures has been proven to be an effective strategy to overcome the problem of rapid capacity fading to a certain extent. Herein, an interestingly interconnected quasi-ball-in-ball nanostructure SnO2/carbon composite, denoted as Cs@void@SnO2@C, has been successfully fabricated by a simple and novel strategy. When used as anode materials for lithium-ion batteries, the Cs@void@SnO2@C exhibits high lithium storage and long cycling performance, delivering a reversible capacity of 793.7 mAh g−1 after 450 cycles at 200 mA g−1, and a reversible capacity of 486.3 mAh g−1 after 1000 cycles even at 1000 mA g−1. The uniquely interconnected quasi-ball-in-ball structure should be responsible for the good electrochemical performance, which is further confirmed by comparing with two control samples of Cs@SnO2@C and Cs@SnO2.