Stable and high-capacity Si electrodes with free-standing architecture for Lithium-ion batteries

To meet the increasing demands of electric vehicle applications for long ranges, Si-based materials have been intensively investigated as promising candidates for outstanding anodes of lithium-ion batteries over the past 2 decades. In the meantime, various nanotechnologies enable accommodation of the huge volume change of Si during charge/discharge processes, which significantly improves the performances of Si-based anodes. However, a large amount of binders and conductive agents are still required for the reliable performance of Si anodes. Herein, we have introduced free-standing Si electrodes, which show suppressed swelling property (31.29%) after the 100th cycle in spite of no binders. Carbon-coated Si nanoparticle (NP) via thermal decomposition of acetylene (C2H2) gas was confined in the bundles of copper nanowires (Cu NWs) that provide not only high electrical conductivity but also accommodation of volume changes of Si NPs. The carbon coating layer helped to form a stable solid electrolyte interface ...