Carbon Wrapped Nanosilicon with Reserved Void for High Capacitance and Stable Lithium‐Ion Battery Anode

Applicable anode with an industrial‐compatible production process, high capacitance, and good stability is of great importance for the development of lithium‐ion battery technology. In this work, a composite of carbon/silicon with a well‐reserved void is prepared. The composite shows uniform spherical morphology with rich inside voids between the silicon core and carbon shell. Benefiting from the porous structure, the volumetric variation of silicon in the composite as anode during the charging/discharging process can be reversible, and its good anode stability can be achieved in comparison with carbon‐coated silicon without void. The gravimetric capacitance of it reaches 1579.5 mAh g −1 . After 100 cycles, the capacitance retention achieves 91.7% compared with 79.8% of carbon‐coated silicon without void.