Kinetic favorability of Ru-doped LiNi sub(0.5)Mn sub(1.5)O sub(4) for high-power lithium-ion batteries

Pristine and Ru-doped LiNi sub(0.5)Mn sub(1.5)O sub(4) samples were synthesized using a simple carbon combustion method. Crystallographic analyses combining X-ray diffraction and Rietveld refinement confirmed that formation of the Li sub(x)Ni sub(1-x)O-like impurity phase is prevented and that the lattice parameter increases as a result of Ru doping. Furthermore, its structure is partially changed to the more disordered spinel phase (Fd3m). Both this structural change and the disappearance of the impurity phase greatly enhance the rate capability and cyclic retention of LiNi sub(0.5)Mn sub(1.5)O sub(4).