A novel Si/Sn composite with entangled ribbon structure as anode materials for lithium ion battery

Abstract

A novel Si/Sn composite anode material with unique ribbon structure was synthesized by Mechanical Milling (MM) and the structural transformation was studied in the present work. The microstructure characterization shows that Si/Sn composite with idealized entangled ribbon structured can be obtained by milling the mixture of the starting materials, Si and Sn for 20 h. According to the calculated results based on the XRD data, the as-milled 20 h sample has the smallest avergae crystalline size. It is supposed that the flexible ribbon structure allows for accommodation of intrinsic damage, which significantly improves the fracture toughness of the composite. The charge and discharge tests of the as-milled 20 h sample have been performed with reference to Li + /Li at a current density of 400 mA g1 in the voltage from 1.5 to 0.03 V (vs Li/Li +) and the result shows that the initial capacity is 1/41400 mA h g '1, with a retention of 1/41100 mA h g '1 reversible capacity after 50 cycles, which is possible serving as the promising anode material for the lithium ion battery application.