Promoting Lithiation Activity and Durability of Silicon Anodes by Nitrogen‐Doped Carbon Nanosheet Skeleton

Silicon (Si) is recognized to be a large‐capacity anode candidate for high energy Li‐ion batteries. However, the low electrical conductivity and gigantic volume change of Si dramatically degrade its lithiation activity and durability, which remains a longstanding challenge. Herein, we demonstrate a nanoconfined strategy by wrapping silicon into a porous nitrogen‐doped carbon sheet skeleton. The nitrogen‐doped carbon is of dual benefits for the improvement in electrical conductivity and lithiophilicity, which significantly promotes the lithiation activity of Si. Additionally, the porous and resilient carbon framework can sustain the mechanical strain of Si caused by volume expansion/shrinkage. As a consequence, the Si‐hybrid electrode achieves an increased lithiation capacity of 1260 mAh g −1 and superb cycling lifespan. The underlying insights for the enhanced reactivity are systematically probed by a series of electrochemical techniques. The present study paves a powerful design tactic for developing high‐capacity and durable Si anodes in lithium chemistry.