High capacity tin-iron oxide-carbon nanostructured anode for advanced lithium ion battery

A novel nanostructured SneFe2O3eC anode material, prepared by high-energy ball milling, is here originally presented. The anode benefits from a unique morphology consisting in Fe2O3 and Sn active nanoparticles embedded in a conductive buffer carbon matrix of micrometric size. Furthermore, the Sn metal particles, revealed as amorphous according to X-ray diffraction measurement, show a size lower than 10 nm by transmission electron microscopy. The optimal combination of nano-scale active materials and micrometric electrode configuration of the SneFe2O3eC anode reflects into remarkable electrochemical performances in lithium cell, with specific capacity content higher than 900 mAh g1 at 1C rate (810 mA g1 ) and coulombic efficiency approaching 100% for 100 cycles. The anode, based on a combination of lithium conversion, alloying and intercalation reactions, exhibits exceptional rate-capability, stably delivering more than 400 mAh g1 at the very high current density of 4 A g1. In order to fully confirm the suitability of the developed SneFe2O3eC material as anode for lithium ion battery, the electrode is preliminarily studied in combination with a high voltage LiNi0.5Mn1.5O4 cathode in a full cell stably and efficiently operating with a 3.7 V working voltage and a capacity exceeding 100 mAh g1.