Self-assembled three-dimensional Si/carbon frameworks as promising lithium-ion battery anode

Silicon, the most prospecting anode material for lithium batteries, has been receiving enormous attention, but silicon-based composite materials exhibit severe problems of structural instability and insufficient electron/ion conductivity, which is a major bottleneck limiting its practical applications. Herein, a three-dimensional (3D) silicon/carbon framework, CHSP, is designed to solve this problem. The nano-Si particles are well fixed by the interconnected porous conducting network, which not only enhances the ion/electron transport, but also buffers the volume change of Si effectively. As a result, the CHSP exhibits satisfying rate performance and a reversible capacity of as high as 1332 mA h g −1 at 1000 mA g −1 for 200 cycles. This research provides a practical approach to improve silicon anode performance in aspects of cycling stability and facile 3D structures synthesis process. • 3D porous structure prepared by self-assembly and freeze-drying methods. • 3D porous conductive network suppresses the volume expansion of the electrode. • The CHSP anode material exhibits 1332 mA h g −1 at 1 A g −1 after 200 cycles.