Electrochemically-induced Amorphous to Crystalline Transformation in Niobium Oxide Electrodes for Lithium-Ion Batteries

Intercalation-type metal oxide electrodes are promising negative electrode materials for safe and stable operation of rechargeable lithium-ion batteries due to the reduced risk of Li plating at low voltages. Nevertheless, lower energy and power density along with cycling instability remain a bottleneck for their implementation, especially for desirable fast charging applications. Recent studies have shown enhanced electrochemical charge storage in metal oxide electrodes that contain intentional structural defects (e.g., vacancies and interstitials). In this talk, we will discuss an electrochemically driven amorphous-to-crystalline (a-to-c) transformation in a nanoporous Nb₂O₅ material for Li-ion storage. Through integrated experimental and computational study, we elucidated the mechanism of multi-electron transfer reaction in the a-to-c Nb2O5 electrode as well as its enhanced kinetics for Li-ion batteries.