The electrochemical behaviors of NaF dual battery based on the hybrid electrodes of nano-bismuth@CNTs

The NaF dual-ion battery was demonstrated as potential battery where fluoride and sodium ions were extracted from NaF electrolyte respectively during discharging; while the charging process causes the release of ions to the electrolyte. However, previous studies reveal that electrode configuration with large-sized particles will significantly reduce the energy density and stability. Herein, we proposed a novel hybrid electrode assembly of bismuth nanoparticles/carbon nanotubes (nano-Bi@CNTs), which could achieve the excellent electrochemical stability. The new NaF dual-ion battery, consisting of nano-Bi@CNTs-Na0.44MnO2 (NMO), demonstrates a high specific capacity of 109.5 mAh/g after 80 cycles with 100 mA/g current density. Moreover, the electrochemical mechanism of fluoride ion in this system was comprehensively investigated. The current research is significant for the novel anion energy storage system.