Preparation and study of carbon nano-onion for lithium storage

Carbon nano-onions were prepared by burning castor oil. The as-prepared carbon nano-onions were characterized by scanning electron microscopy and transmission electron microscope to confirm the nano-onion structures. The carbon nano-onions were used as anodes for rechargeable Li-ion batteries and demonstrated high reversible capacity and relatively good rate capability. The electrochemical performance can be attributed to the unusual surface properties and unique structural features of the carbon nano-onion anode, which amplify both surface area and extensive intermingling between curved graphite layer over small length scales, thereby leading to fast kinetics and short pathways for both Li ions and electrons.