Improvement of the electrochemical properties of SnO₂ electrodes for lithium rechargeable battery using protective Ta ₂O₅ thin films

We have investigated the effect of the protective Ta₂O ₅ thin films on the electrochemical behaviors of test cells fabricated with SnO₂ electrodes. It is shown that for the cells made with the single SnO₂ electrodes, their cycling performance is rapidly degraded with increasing cycle number. However, the addition of the Ta₂O₅ thin film on the SnO₂ electrodes results in a slow degradation of capacity. The improved electrochemical behaviors of the cells made with the Ta₂O₅ film-coated SnO₂ electrodes are attributed to the combined roles that the Ta₂O ₅ films serve as a protective layer and facilitate the passage of Li ions during cycling.