Preparation and Characterization of Nanocrystalline Li₇Si₃ Alloy

To study the characteristics of nanostructured anode materials of Li batteries, the nanocrystalline Li-Si alloy was prepared. Nanocrystalline Li₇Si₃ alloy was prepared with the optimized processing route including a series of procedures as cast of polycrystalline Li₇Si₃ ingot, ball milling to obtain the amorphous powder and spark plasma sintering to prepare the nanocrystalline Li₇Si₃ bulk. The crystal structure was determined using the Rietveld refinement method and the Young's modulus was measured.Resultsshow that the prepared nanocrystalline Li₇Si₃ has larger lattice constants compared with those of the conventional polycrystalline counterpart, i. e., a = b = 0. 445 2 nm, c = 1. 823 9 nm, and unit cell volume V_o= 0. 313 070 nm³. The unit cell volume is 1. 35% larger than that of the coarse-grained polycrystalline counterpart with a value of V_o= 0. 308 886 nm³. The Young's modulus of the nanocrystalline Li₇Si₃ was as (30. 6 ± 2. 4) GPa.