Mesoporous Anatase TiO2 Electrodes Modified by Metal Deposition: Electrochemical Characterization and High Rate Performances

We propose the optimization of the electrochemical properties of TiO2 mesoporous anatase electrodes for lithium-ion batteries by coating with thin Cu or Sn metal layers. The vacuum deposition of Cu or Sn causes no changes in the anatase structure. The metal/anatase composite electrodes show improved kinetics of Li insertion/extraction reactions and excellent electrochemical performances in terms of capacity, stability, and fast-cycling abilities. The higher electrochemical performances are ascribed to an enhanced lithium desolvation and wetting properties at the interface between electrode and electrolyte and to faster lithium diffusion into the anatase lattice. Due to the relatively easy modification procedure, the thin metal coating by physical vapor deposition appears to be a very promising optimization method for the development of high rate performance materials for lithium-ion batteries.