Nano‐/Microstructured Si/C Composite with High Tap Density as an Anode Material for Lithium‐Ion Batteries

Nanostructured Si materials are plagued by having a limited electrochemical performance and low tap density. Hence, we synthesized a nano‐/microstructured Si/C composite with Si nanoparticles uniformly embedded into a carbon matrix, which had a tap density 5.3 times higher than that of Si nanoparticles. The nano‐/microstructured Si/C composite shows a superior structural stability, which ensures a long cycle life with a capacity of 600 mAh g −1 after 1000 cycles at 420 mA g −1 . Moreover, the carbon matrix can provide three‐dimensional electron‐transfer pathways for Si nanoparticles to improve the electronic conductivity. Therefore, the Si/C composite anode material also exhibits an outstanding rate capability, which can still deliver a capacity of 510 mAh g −1 at 5 C. Thus, the nano‐/microstructured Si/C composite with a high tap density possesses great potential in view of practical applications.