Co3O4 particles were embedded in the nanopores of hard carbon spherules (HCS) by thermal decomposition of cobalt compound in long carbon-chain alcohols at low temperature. The electrochemical performance of the composite was evaluated by galvanostatic cycling and cyclic voltammetry. The significantly improved electrochemical performance of the composite material as anode for lithium-ion batteries is attributed to the high Li-storage capacity of Co3O4 and the prevention of aggregation of the Co3O4 nanoparticles embedded in stable HCS. (C) 2004 The Electrochemical Society.