LiNi0.5Mn1.5O4 (LNMO) thin films were prepared by radio frequency magnetron sputtering, followed by thermal annealing in ambient atmosphere. The growth of the films has been studied as a function of deposition temperature, atmosphere, and annealing temperature. Electrochemical properties of LNMO thin-film cathodes were investigated using galvanostatic charge/discharge and cyclic voltammetry against a lithium anode. The initial capacity and capacity retention of the films are highly dependent on the crystallinity and morphology of the films. LNMO thin film grown at 400 degrees C in an Ar/O-2 atmosphere and annealed at 550 degrees C exhibits good crystallinity and well-defined grain structure. Also it exhibits larger capacity and higher cyclic stability under a high cutoff voltage of 4.9 V. (C) 2017 Published by Elsevier B.V.