Encapsulating silicon nanoparticles into N-doped carbon film as a high-performance anode for lithium ion batteries

A flexible strategy is to exploit encapsulating Si nanoparticles into N-doping carbon film (Si-NC) that can effectively localize the Si nanoparticles, thereby solving the problem of serious volume change during cycling as well as facilitating the fast diffusion of Li+, and thus achieving improved anode performance. A maximum capacity of 883.1mAhg−1 at the current density of 100mAg−1 after 50 charge and discharge processes is achieved for Si-NC. Even at a large current density of 2000mAg−1, a specific capacity of 415mAhg−1 is maintained. Moreover, the charge capacity can still almost recover the initial capacity as the current density is reverted to 100mAg−1, indicating that Si-NC has a superior rate performance in lithium storage. This facile synthesis route provides a new perspective to produce Si/C composite at a low cost and large scale with good electrochemical performance.