Mixed‐Phase Niobium Oxide as a Durable and Ultra‐Fast Charging Anode for High‐Power Lithium‐Ion Batteries

Abstract

AbstractThe development of low‐cost, high‐power lithium‐ion batteries requires durable anode materials that can store and release lithium quickly. Here a mixed phase of H‐Nb2O5 and M‐Nb2O5 (denoted as d‐H,M‐Nb2O5) that demonstrates excellent performance as an anode material for lithium storage is reported. Experimental and computational analyses reveal several salient features of d‐H,M‐Nb2O5. First, the edge‐sharing arrangement between the mixed niobium oxygen polyhedral block structures helps alleviate volume expansion during cycling, thereby enhancing stability and reversibility. Second, the mixed‐phase structure facilitates a continuous pathway for lithium ion adsorption These characteristics allow for sequential transport of lithium ions, enabling fast charging. As a result, the d‐H,M‐Nb2O5 electrode material exhibits a high capacity of 142 mAh g−1 at an ultra‐fast charging rate of 100 C, while maintaining 85% of its initial capacity after 5000 cycles. Moreover, its practical feasibility is established by demonstrating full‐cell performance at a 5 C discharge/charge rate (13 mA cm−2), maintaining 79% of its capacity over 1000 cycles.