Bilayer-coating of MnO and N-doped carbon on SiO₂microspheres as a high-performance anode for flexible li-ion batteries

Silicon-based anodes are promising for lithium-ion batteries (LIBs) due to their high capacity and low voltage plateau but suffer from poor conductivity, volume expansion, and unstable solid electrolyte interphase (SEI) growth, causing rapid capacity loss. To overcome these challenges, this work fabricates a novel bilayer-coating of MnO and N-doped carbon (NC) on SiO₂microspheres. The MnO layer enhances electrochemical kinetics, while the outer carbon coating improves conductivity and structural stability, reducing volume changes during cycling. This unique SiO₂@MnO-NC composite structure effectively suppresses volume expansion and stabilizes the electrode. A full cell employing SiO₂@MnO-NC as anode and nickel‑cobalt‑aluminum oxide (NCA) as cathode displayed excellent rate capability and long-term cycling, delivering a high capacity (157 mAh/g) with ∼73 % capacity retention and ∼ 99 % Coulombic efficiency over 250 cycles. SiO₂@MnO-NC//NCA full cell achieves an energy density of 619 Wh/kg and power density of 556 W/kg. These findings demonstrate the strong potential of SiO₂@MnO-NC composite as a high-performance anode material for next-generation LIBs.