Finely crafted polyaniline cathode for high-performance flexible quasi-solid-state Zn-ion battery

Abstract Flexible aqueous Zn-ion batteries have aroused great interest as an emerging energy storage technology in smart/wearable electronics due to their low cost, high energy density, good safety, and flexibility. However, the construction of excellent cathode and anode is still a key step for the Zn-ion batteries development. Herein, we report a rechargeable flexible quasi-solid-state (FQSS) Zn-ion battery assembled with free-binder polyaniline/molecular-decorated carbon cloth (PANI/mCC) cathode and zinc nanosheet/CC (Zn/CC) anode sandwiched by poly(vinyl alcohol)/Zn(CF3SO3)2 gel electrolyte. The nanostructured PANI arrays and Zn sheets oriented on the flexible substrates afford rapid transport channels for electrolyte ions and endow electrodes enough flexibility. Consequently, the constructed FQSS Zn-ion battery exhibits outstanding energy/power densities of 185.7 Wh kg−1/9742 W kg−1 and good capacity retention of 80% after 1000 charge-discharge cycles at 3.3 C. Impressively, the assembled flexible device can accommodate a series of bending states and show stable performance.