The Ni and Sn-embedded carbon nanofiber (Ni-Sn/CNF) nanocomposites as anode materials were prepared by using electrospinning technique and optimum thermal process. The fine structure of Ni-Sn/CNF was scrutinized by EXAFS. The nanocomposite prepared at 700 degrees C had disordered Ni3Sn2, disordered NiO, amorphous SnOx and crystalline SnO2 phases created as tiny particles in the carbon nanofibers (CNF). The 100th discharge capacity of Ni-Sn/CNFs were ranked as follows by their preparation temperature: 700 degrees C (641 mAh g(-1))>600 degrees C (573 mAh g(-1))> 800 degrees C (559 mAh g(-1)), and their initial coulomb efficiencies were ranked by preparation temperature: 700 degrees C (60%)>600 degrees C (58%)>800 degrees C (55%). The excellent specific discharge capacity and cycle retention of the sample prepared at 700 degrees C were attributed to the formation of Ni3Sn2 intermetallic compounds, the buffering role of the CNF, and the good distribution of active particles by electrospinning. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3560433]