Mechanochemical synthesis of Li–Mn–O spinels: positive electrode for lithium batteries

Li-Mn-O oxides were synthesized by mechanochemistry from a stoichiometric mixture of Li 2 O and MnO 2 using various grinding times (0 < t milling < 15 h). X-ray diffraction patterns of the ground samples (t milling < 10 h) exhibit the same features as LiMn 2 O 4 spinel structure (SG: Fd3m) with, however, a slight discrepancy in the lattice parameter (a cub ) suggesting a non-stoichiometry of the Li-Mn-O oxides, a cub increases with milling time to reach for 8 h of grinding a value of 8.24 A similar to stoichiometric LiMn 2 O 4 . As a matter of fact, after 8 h of milling, mechanosynthesized Li-Mn-O spinel-type oxide shows quasi-identical electrochemical performances as high temperature LiMn 2 O 4 ground for 1 h.