A comparative study of free-standing LiFePO₄/sorted single-walled carbon nanotubes (SWNTs) and conventional LiFePO₄ cathode was carried out. The free-standing cathode was prepared by traditional slurry method followed by a surface peel-off technique. Our experiments revealed that the energy density of free-standing LiFePO₄/sorted SWNTs cathode film having a trace amount (0.0075%) of sorted SWNTs is comparable to that of a conventional LiFePO₄ cathode having 10% carbon black and a current collector foil. Both cathode types exhibit good cycling stability performance relative to each other. Moreover, the free-standing cathode exhibits good flexibility and robust mechanical strength which has the potential to be applied to flexible lithium ion batteries.