Graphitic N-CMK3 pores filled with SnO2 nanoparticles as an ultrastable anode for rechargeable Li-ion batteries.

The incorporation of ultrafine SnO 2 particles inside N-doped ordered mesoporous carbon (N-CMK3) is suggested as a method to prepare an ultrastable anode material for Li-ion batteries. Sn nanoparticles formed by chemical reduction of SnCl 4 inside N-CMK3 pores are spontaneously reoxidised by dissolved oxygen, resulting in the formation of ultrafine SnO 2 inside N-CMK3 pores. This SnO 2 @N-CMK3 exhibits superior capacity, cyclability, and rate capability. Over 100 cycles at a rate of 0.1C, SnO 2 @N-CMK3 maintains a specific capacity of 635 mAh g−1, corresponding to a capacity retention of 86.6%. Over 1000 cycles at the rate of 0.5C, SnO 2 @N-CMK3 can deliver a capacity of 433 mAh g−1. At an ultrahigh rate of 5C, SnO 2 @N-CMK3 still delivers a capacity higher than that of commercial graphite. The full cell, composed of an SnO 2 @N-CMK3 anode, LiCoO 2 cathode, and sacrificial Li electrode, presents excellent performance, better than previous reports of Li-ion cells. By employing a sacrificial Li electrode, the issue related to the low Coulombic efficiency of SnO 2 @N-CMK3 in the first few cycles and the pre-lithiation SnO 2 @N-CMK3 electrode can be successfully addressed. Image 1 • Ultrafine SnO 2 particles are filled inside mesopores of N-CMK3. • SnO 2 @N-CMK3 exhibits the reversible capacity of 635 mAh g−1 at the rate of C/10. • An original three-electrode full cell using SnO 2 @N-CMK3 anode is designed. • Sacrificial Li electrode in the full cell improves coulombic efficiency. • The full cell delivers 608 mAh g−1 with 83.8% retention over 200 cycles. [ABSTRACT FROM AUTHOR]