LiCo1/3Ni1/3Mn1/3O2 cathode electrodes were prepared using the doctor blade technique, where distilled water was used instead of ordinary NMP as the solvent. A serious problem is caused because the dispersion of hydrophobic carbon particles used as a conducting additive is difficult in water solvent. In this study, as a novel technique for the carbon particle dispersion, low-temperature liquid-phase plasma treatment was applied. The surface of carbon particle was converted from hydrophobic to hydrophilic via OH radical formation. The treatment enabled us to obtain stable colloidal dispersion of the carbon particles. The film electrode with smooth surface and no aggregates was easily attained. The electrode prepared using the water-based slurry has superior cycling performance and slightly-poorer rate capability compared to that of the electrodes prepared using the NMP-based slurry. (C) 2016 Elsevier B.V. All rights reserved.