A Li6.75La3Zr2Al0.25O12 (LLZAO)-coated LiNi0.7Co0.15Mn0.15O2 (LNCM) cathode is synthesized using a simple one-step calcination process. LLZAO is a fast ionic conductor that could effectively enhance the lithium-ion diffusion at the electrode/electrolyte interface. The LLZAO-coated LNCM exhibits relatively better electrochemical performance than pristine LNCM, with a superior initial discharge capacity of 191 mAh g(-1) and good rate capability at a high rate of 5C. Furthermore, electrochemical impedance spectroscopy measurement indicates that the interfacial resistance of the LLZAO-coated sample is lower than that of pristine LNCM, which strongly indicates that coating LNCM in LLZAO improves the lithium-ion transport at the electrode/electrolyte interface. (C) The Author(s) 2017. Published by ECS. All rights reserved.