An all-organic aqueous potassium dual-ion battery

Benefiting from the environmental friendliness of organic electrodes and the high security of aqueous electrolyte, an all-organic aqueous potassium dual-ion full battery (APDIB) was assembled with 21 M potassium bis(fluoroslufonyl)imide (KFSI) water-in-salt as the electrolyte. The APDIB could deliver a reversible capacity of around 50 mAh g(-1) at 200 mA g(-1) (based on the weight of total active materials), a long cycle stability over 900 cycles at 500 mA g(-1) and a high coulombic efficiency of 98.5%. The reaction mechanism of APDIB during the charge/discharge processes is verified: the FSI- could associate/disassociate with the nitrogen atom in the polytriphenylamine (PTPAn) cathode, while the K+ could react with C=O bonds in the 3,4,9,10-perylenetetracarboxylic diimide (PTCDI) anode reversibly. Our work contributes toward the understanding the nature of water-into-salt electrolyte and successfully constructed all-organic APDIB. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

The research successfully assembled an all-organic aqueous potassium dual-ion full battery with high safety, reversible capacity, long cycle stability, and high coulombic efficiency.