The electrochemical properties of Sn-M (M = Cu, Mg and Fe) bi-alloy nanoparticles prepared by DC arc-discharge method have been studied when these nanoparticles serve as the anode materials in Li-ion batteries (LIBs). Among all the alloy electrodes, the Sn-Fe electrode has the best initial specific capacity that maintains at about 227.3 mAh g(-1) within 20 cycles. The intermetallic compounds in the nanoparticles have been characterized and thermodynamics analysis is introduced to elucidate the energy balance of their formation mechanism. As the electrochemical behaviours of the various alloy nanoparticles are different, we conclude that the present intermetallic compounds eventually determine the lithium-ion storage ability as well as the cyclic stability during the lithiation/delithiation process. (C) 2017 Elsevier B.V. All rights reserved.