Search

The rising demand to electrify power‐intensive energy devices and systems, as well as fast charging, has imposed a great challenge in current chemistries for lithium‐ion batteries (LIBs), whose rate capabilities are predominantly restricted by the conventional graphite anode. Niobium pentoxide (Nb2O5) is a promising high‐rate anode material for LIBs with extraordinary rate performance beyond 5 C and good theoretical capacity (~202 mAh ⋅ g−1). With many possible crystal structures, Nb2O5 has a complicated family of different polymorphs, each of which can possess distinct electrochemical properties, specific capacity, cycling stability, and rate capability. This special feature of Nb2O5 makes it a challenging material to understand and requires a comprehensive investigation of every one of its polymorphs. In this paper, we summarize the state‐of‐the‐art research on Nb2O5 polymorphs for LIBs, with an emphasis on the advanced characterisation techniques that have been used to probe the electrochemical processes of Nb2O5. Key findings related to Nb2O5 that have emerged from the previous studies are highlighted, and new scientific questions that are important for its scale‐up and commercialization are proposed for future research. [ABSTRACT FROM AUTHOR]