Nanostructured Polypyrrole Composite Aerogels for a Rechargeable Flexible Aqueous Zn‐Ion Battery with High Rate Capabilities

Abstract

Aqueous Zn‐ion batteries usually suffer from an inferior rate capability because of high internal resistance. Herein, nanostructured polypyrrole (PPy) composite aerogels are fabricated as the flexible cathode of an aqueous Zn‐ion battery. Highly porous composite aerogels enable easy ion diffusion toward nanostructured PPy and a low internal resistance of 1.5 Ω cm −2 . A high power density of 11.7 kW kg −1 is thus achieved for the aqueous Zn‐ion battery at a satisfactory energy density of 64.0 Wh kg −1 , superior to other aqueous batteries and supercapacitors. The Zn‐ion battery exhibits good flexibility, as illustrated by high‐capacity retention of 80.3% after 1000 bending cycles. The flexible Zn‐ion battery with high rate capabilities could find practical applications in wearable electronics requiring rapid charge.