Artificial solid electrolyte interphase modified porous SiOx composite as anode material for lithium ion batteries

High-performance electrode materials with intelligent design hold the promise for the development of lithium ion batteries regarding high energy density and long cycling life. Herein, we report an artificial solid electrolyte interphase (SEI) modified porous SiOx anode (P-SiOx) prepared by a facile in-situ polymerization of tannin (PTN) under alkaline condition, forming an elastic polymer layer surrounding P-SiO(x )particles. The as-prepared P-SiOx@PTN composite demonstrates higher initial Coulombic efficiency (ICE) and stronger mechanical property than the P-SiOx. Consequently, the outer elastic and electric buffer layer ensures the composite showing a high reversible capacity of 1616 mAh g(-1) at 0.1 C and exceptional long-term cycling performance. Moreover, when coupled with LiNi0.8Mn0.1Co0.1O2 cathode, high reversible capacity (123 mAh g(-1)) and good capacity retention (83 mAh g(-1) after 300 cycles) at 0.5 C are achieved. This facile method constructing the artificial solid electrolyte interphase with enhanced mechanical and electrochemical properties by the in-situ PTN is of great promise for Si-based anode materials.