Structure-Modified Anode Material for Regenerable Organic Potassium-Ion Batteries

As the mismatch between the growing demand for energy storage and the scarcity of resources for the current lithium-ion batteries (LIBs) escalates, it is urgent to seek out an alternative solution for energy storage devices. Potassium-ion batteries (PIBs), with their resource abundance and analogous electrochemical potential, are expected to be a promising contender. Herein, by structure modification, a novel organic anode material of 2,5-bis(methoxycarbonyl)-3,6-dioxocyclohexa-1,4-dienolate (K2dmcdbq) is synthesized and composited with carbon nanotubes to realize the properties of high capacity, high rate, cycle retention, and regenerability. The unique cation storage and capacity degradation mechanisms of the PIBs are studied, and the electrochemical performance is thoroughly recovered by a chemical regeneration process. Combined with the perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) cathode, the environmentally friendly all-organic potassium full cells achieve a regenerable energy density of 119 Wh kg–1 and a power density of 113 W kg–1, which provides a fresh sight of material design for electrochemically active organic materials.