Porous lithium nickel cobalt manganese oxide hierarchical nanosheets as high rate capability cathodes for lithium ion batteries

Novel 2D LiNi_1/3Co_1/3Mn_1/3O₂ hierarchical nanosheets are successfully synthesized through a simple sol-gel strategy with ethanol dispersion of carbon nanotubes as addictive. The nanosheets with thickness of ∼100 nm appear porous and are formed by 100 nm nanoparticles. As cathode for lithium ion battery, the 2D porous hierarchical nanosheets demonstrate high specific capacity of 137.7 mAh g^-1 at 20C (1C = 200 mA g^-1), which is much higher than those of its counterparts. The high capacity can be still maintained during 100 charge/discharge cycles and the capacity retention is up to 90.1%. The excellent rate capability and cyclability may be attributed to the distinct 2D porous hierarchical structure.