High-performance Sn@carbon nanocomposite anode for lithium batteries

Nanosize tin particles (Sn-PMCMT) embedded in electrically conducting porous multichannel carbon microtubes are synthesized by co-electrospinning followed by air stabilization and carbonization in Ar/ H2 atmosphere. Scanning and transmission electron microscopy show that the material is nanostructured with nanosize Sn particles well embedded into the carbon host matrix. Composite electrodes prepared using Sn-PMCMT, Super-P carbon and Na-carboxymethylcellulose as binder, exhibit a superior rate capability and exceptional cycle life in cell tests at room temperature. Discharge capacities as high as 632 mAh g1 at 0.7 C rate are obtained during the first galvanostatic cycles. The delivered capacities are still in excess of 350 mAh g1 after 600 cycles, most of them performed at 2 C rate. These outstanding results represent the highest performance so far reported for this type of electrode.