Highly Flexible and Structurally Stable Oriented Conductive Framework for Deformation-Tolerant Zn-Ion Batteries

Abstract

Oriented conductive frameworks with high flexibility and mechanical stability can facilitate efficient electron and ion transport in complex-shaped power supplies, boosting the reliability and function of the next-generation flexible electronics. Here, a multi-direction deformable and structurally stable oriented conductive framework is presented, which is mediated by hydrogen bonding interactions of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), through self-assembly on a porous wood template. The framework exhibits excellent flexibility in three dimensions, restoring integrity and maintaining constant conductivity across diverse deformations, even after enduring 5000 bending cycles (angle: 180°) and soaking in water for 6 months. Utilizing its unique oriented structure and flexible bending capability, a flexible zinc-iodine battery is developed, which demonstrates a high areal capacity of 3.2 mAh cm⁻² and an energy density of 3.8 mWh cm⁻². Moreover, the battery is capable of high-current charging and discharging at 20 mA cm⁻², with an impressive areal capacity of 1.9 mAh cm⁻², far superior to the existing flexible zinc-ion batteries. It also demonstrates excellent electrochemical and mechanical stability under various deformations, including bending, twisting, and rolling, providing stable energy for a commercial toy car and a flexible screen even under hammer strikes and repeated bending. This work advances the development of high-performance, deformation-tolerant, flexible batteries.