Flexible Cathode Enabled by Ultralong Na2V6O16·3H2O Nanowire for High Rate and Durable Aqueous Zinc Ion Batteries

Aqueous zinc ion batteries (ZIBs) have garnered increasing attention owing to their safe aqueous electrolyte and suitable energy and power density. However, the development of appropriate cathode materials for commercialization remains a challenge. Herein, we report a flexible binder-free film cathode composed of hydrated sodium vanadate nanowires and carbon nanotubes (NaVO/CNT). The as-prepared film cathode exhibits a remarkably high rate performance, delivering a capacity of 402 mAh g–1 at 0.1 A g–1 and 284 mAh g–1 at 6 A g–1. Furthermore, excellent long-term stability is achieved with a retention rate of 90.04% after 5000 cycles at 4 A g–1. This cathode demonstrates outstanding performance compared with those of other sodium vanadate-based cathodes in aqueous ZIBs. Additionally, the co(de)insertion mechanism of H+ and Zn2+ ions is verified.