Enhancing the cycle stability of SiO@C anode by in situ formed Mn2SiO4 interphase for Li-ion batteries

Decorating transition metal oxide in combination of carbon coating has been verified as an effective way to boost the cycling stability of SiO anode. However, the weak bonding between the transition metal oxides and SiO matrix tends to weaken the modification effect. Herein, SiO@C anode is modified with in situ formed Mn 2 SiO 4 interphase through solid-state reaction between SiO and the hydrothermally grown MnO 2 at the presence of resorcinol-formaldehyde (RF) resin coating layer. The Mn 2 SiO 4 interphase buffers the volume change of the composite anode through a reversible conversion reaction, leading to greatly enhanced cycle stability. For the optimized SiO/Mn 2 SiO 4 @C anodes, capacity retention ratios higher than 84% are preserved after 500 cycles at 1.0 A g −1 , significantly outperforming that of the SiO@C anode (65%). This work provides a facile strategy to fully exploit the modification effect of transition metal oxide on SiO-based anode, thus paving the way for high energy density Li-ion batteries with superior cycling stability.