Silicon sub-oxides, SiOx (0 < x < 1) can be regarded as a promising anode material for high performance Li-ion batteries for its unique electrochemical reactions to Li. We designed and synthesized the columnar-shape SiOx nanoconifers (0.9 < x < 1), directly self-organized on metallic NiSix nanowires (NWs) for its anodic use in Li rechargeable batteries. The half-cell incorporating SiOx nanoconifers/NiSix NW heterostructures displays good cyclic retention and rate capability, which are attributed to the structural and kinetic stability of the hierarchical SiOx nanoconifers rigidly supported by metallic NiSix core NWs by providing a reversible electrochemical route with a lower activation energy. (C) 2012 Elsevier B.V. All rights reserved.