Microporous honeycomb-shaped LiNi0.5Mn0.5O2 (H-LNMO) cathode materials were prepared by a simple sol-gel method using surfactants. Scanning electron microscopy images of the prepared LNMO show that the pore size and wall thickness are approximately 3.3 mu m and 233 nm, respectively. The honeycomb-shaped LNMO (5.33m(2)/g) has a larger specific surface area than does the conventional nano-sized LNMO (4.50m(2)/g). The LNMO with a larger surface area shows an enhancement in discharge capacity for all C-rates compared with conventional nano-sized LNMO.