Hierarchical Structured Cu/Ni/TiO Nanocomposites as Electrodes for Lithium-Ion Batteries.

The electrochemical performance of anodes made of transition metal oxides (TMOs) in lithium-ion batteries (LIBs) often suffers from their chemical and mechanical instability. In this research, a novel electrode with a hierarchical current collector for TMO active materials is successfully fabricated. It consists of porous nickel as current collector on a copper substrate. The copper has vertically aligned microchannels. Anatase titanium dioxide (TiO) nanoparticles of ∼100 nm are directly synthesized and cast on the porous Ni using a one-step process. Characterization indicates that this electrode exhibits excellent performance in terms of capacity, reliable rate, and long cyclic stability. The maximum insertion coefficient for the reaction product of LiTiO is ∼0.85, a desirable value as an anode of LIBs. Cross-sectional SEM and EDS analysis confirmed the uniform and stable distribution of nanosized TiO nanoparticles inside the Ni microchannels during cycling. This is due to the synergistic effect of nano-TiO and the hierarchical Cu/Ni current collector. The advantages of the Cu/Ni/TiO anode include enhanced activity of electrochemical reactions, shortened lithium ion diffusion pathways, ultrahigh specific surface area, effective accommodation of volume changes of TiO nanoparticles, and optimized routes for electrons transport.