ABSTRACT Organic cathode materials (OCMs) are promising sustainable alternatives to inorganic counterparts for next‐generation batteries, yet their widespread application is largely hindered by intrinsically low electrical conductivity (below 10 −6 S cm −1 ) and material dissolution. The vast chemical space for exploration complicates the discovery of optimal OCMs. In this work, we utilized a machine learning (ML)‐based discovery process with a pretrained transformer model in ZINC organic molecules database, yielding a couple of potential high‐performance OCMs candidates, including isoindigo‐type redox units. The output of such efficient screening inspires the design of poly‐benzodifurandione (PBFO) as a free‐standing cathode material for high‐performance Li‐ion and Na‐ion storage. The flexible PBFO film exhibits a breakthrough conductivity of 5.9×10 2 S cm −1 , setting a new benchmark for additive‐free organic cathodes. The neat PBFO cathodes achieve a reversible capacity of 262 mAh g −1 averaging at 2.5 V versus Li + /Li at 25 mA g −1 , delivering a high electrode‐level energy density of 655 Wh kg −1 , among the highest reported for OCMs. This work provides the first flexible, high‐conductivity organic cathodes without conductive additives and binders, opening a new direction toward viable organic batteries.
Zhang et al. (Sun,) studied this question.