High-performance Zn-ion hybrid supercapacitor enabled by a lightweight polyimide-based anode

Aqueous zinc-ion hybrid supercapacitors (HSCs) have garnered significant attention in energy storage systems due to their unique combination of supercapacitors and battery benefits. However, conventional zinc-ion HSCs utilize Zn metal as anodes, leading to dendrite issues and the limited application of zinc-ion HSCs due to heavy zinc foils. In our work, we constructed lightweight zinc-ion HSCs using a polyimide directly grown on a multiwalled carbon nanotube (PNDIE/MWCNT) as a pseudocapacitor-type anode paired with a polythiophene-coated Na0.55MnO2 carbon cloth-based battery-type cathode (PEDOT-Na0.55MnO2/CC). Benefiting from its lightweight and working mechanism properties, the zinc-ion HSC exhibits a practical energy density of 10.7 Wh kg−1 and a high power density of 192.2 W kg−1, surpassing most previously reported zinc-ion devices. Additionally, the zinc-ion HSC displays excellent retention of 82.1% over 2000 cycles at a scan rate of 15 mV s−1. We believe that our work paves the way for the development of next-generation zinc-ion HSCs by utilizing advanced lightweight metal-free anodes to replace the zinc foil anode.