An Endotenon Sheath-Inspired Double-Network Binder Enables Superior Cycling Performance of Silicon Electrodes

摘要

Silicon(Si)has been regarded as an alternative anode material to traditional graphite owing to its higher theoretical capacity(4200 vs.372 m Ah g;).However,Si anodes suffer from the inherent volume expansion and unstable solid electrolyte interphase,thus experiencing fast capacity decay,which hinders their commercial application.To address this,herein,an endotenon sheathinspired water-soluble double-network binder(DNB)is presented for resolving the bottleneck of Si anodes.The as-developed binder shows excellent adhesion,high mechanical properties,and a considerable self-healing capability mainly benefited by its supramolecular hybrid network.Apart from these advantages,this binder also induces a Li;N/Li F-rich solid electrolyte interface layer,contributing to a superior cycle stability of Si electrodes.As expected,the DNB can achieve mechanically more stable Si electrodes than traditional polyacrylic acid and pectin binders.As a result,DNB delivers superior electrochemical performance ofSi/Li half cells and Li Ni;Co;Mn;O;/Si full cells,even with a high loading of Si electrode,to traditional polyacrylic acid and pectin binders.The bioinspired binder design provides a promising route to achieve long-life Si anode-assembled lithium batteries.