Polyimide@Ketjenblack Composite: A Porous Organic Cathode for Fast Rechargeable Potassium‐Ion Batteries
Chenglin Zhang, Yang Xu, Kaiming He, Yulian Dong, Huaping Zhao, Lukas Medenbach, Yuhan Wu, Andrea Balducci, Thomas Hannappel, Yong Lei
Abstract
Abstract Potassium‐ion batteries (PIBs) configurated by organic electrodes have been identified as a promising alternative to lithium‐ion batteries. Here, a porous organic Polyimide@Ketjenblack is demonstrated in PIBs as a cathode, which exhibits excellent performance with a large reversible capacity (143 mAh g −1 at 100 mA g −1 ), high rate capability (125 and 105 mAh g −1 at 1000 and 5000 mA g −1 ), and long cycling stability (76% capacity retention at 2000 mA g −1 over 1000 cycles). The domination of fast capacitive‐like reaction kinetics is verified, which benefits from the porous structure synthesized using in situ polymerization. Moreover, a renewable and low‐cost full cell is demonstrated with superior rate behavior (106 mAh g −1 at 3200 mA g −1 ). This work proposes a strategy to design polymer electrodes for high‐performance organic PIBs.