Abstract
Aqueous rechargeable Zn-ion batteries (ZIBs) are safe, low cost, and environmentally friendly, yet the realization of both high capacity and long cycling life remains a major challenge. Herein, electrodeposited poly(1,5-naphthalenediamine) nanorods over nanoporous carbon are used as the cathode material to make aqueous ZIBs that can be operated within the voltage range of 0.1 – 1.8 V and have merits of both ionic battery and supercapacitor. Flexible carbon fiber fabric and thick carbon fiber felt are used as current collectors, respectively, to support the polymer/carbon composite with different mass loadings. With using the carbon fabric, flat pouch cells and cable-shaped micro cells are fabricated and show stable electrochemical performances when repeatedly bent at large angles. The pouch cells show maximum energy and power densities of 195 Wh kg‒1 and 104 W kg–1, respectively, and achieve a capacity retention of 91% after 10000 cycles. The prototype cell with using a 3 mm-thick carbon felt shows higher energy densities up to 7.7 mWh cm‒2 and better cycling stability, i.e., 100% capacity retention after 10000 cycles. Also, insights into the charge storage mechanism and superb cycling stability of our new polymer cathode are given.