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

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 1.5cm(-2). A high power density of 11.7kWkg(-1) is thus achieved for the aqueous Zn-ion battery at a satisfactory energy density of 64.0Whkg(-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.