Fluorination Treatment of Conjugated Protonated Polyanilines for High‐Performance Sodium Dual‐Ion Batteries

Abstract The overall performance of dual‐ion batteries (DIBs) is strongly linked to anions storage properties of cathodes. Whereas high energy/power densities and stabilities for DIBs are limited by cathodes. To overcome these barriers, we have designed a novel fluoridized‐polyaniline‐H + /carbon nanotubes (FPHC) as cathode for high‐efficiency PF 6 − storage. F − in PF 6 − is easy to form covalent bond with H on −NH− in FPHC, so that PF 6 − can stably coordinate with FPHC, showing a symmetrical structure. FPHC cathode shows a highly reversible capacity of 73 mAh g −1 at 2 A g −1 after 2000 cycles, which provides a solid base for the advanced sodium dual‐ion batteries (SDIBs) (310 Wh kg −1 /7720 W kg −1 ). Besides, the relative pouch‐type SDIB can drive a vacuum cleaner model with an electric machine. This work may shed light on an up‐and‐coming strategy of robust cathodes for SDIBs.