Assembled Carbon Nanostructure Prepared by Spray Freeze Drying for Si-Based Anodes

Assembled Carbon Nanostructure Prepared by Spray Freeze Drying for Si-Based Anodes

Wanxiong Zhu, Liewen Guo, Kairan Li, Mengxue Shen, Chang Lu, Zipeng Jiang, Huaihe Song, Ang Li

Abstract

Silicon-based materials provide a new pathway to break through the energy storage limits of battery systems but their industrialization process is still constrained by inherent diffusion hysteresis and unstable electrode structures. In this work, we propose a novel structural design strategy employing a modified spray freeze drying technique to construct multidimensional carbon nanostructures. The continuous morphological transition from carbon nanowires to carbon nanosheets was facilitated by the inducement of ultralow-temperature phase separation and the effect of polymer self-assembly. The unique wrinkled carbon nanosheet encapsulation effectively mitigated the stress concentration induced by the aggregation of silicon nanoparticles, while the open two-dimensional structure buffered the volume changes of silicon. As expected, the SSC-5M composite retained a reversible capacity of 1279 mAh g−1 after 100 cycles at 0.2 C (1 C = 1700 mAh g−1) and exhibited a capacity retention of 677.1 mAh g−1 after 400 cycles at 1 C, demonstrating excellent cycling stability. This study offers a new strategy for the development of silicon-based energy storage devices.

Keywords:

Spray Freeze Drying