3D self-supporting PANI/CNT/CC composite cathode coupled with CNF/PAM dual network gel electrolyte for high specific capacity flexible zinc-ion battery

Abstract

In this work, PANI/CNT/CC composite is developed as a positive electrode for flexible zinc-ion battery (ZIB) with the high specific capacity. Assembled flexible batteries are subjected to electrochemical testing. A double grid structure constructed by CNT modification of polyaniline nanofiber network on carbon cloth and CNF modification of PAM gel further improved its flexibility and bending ability. The optimized battery exhibits a high specific capacity of 210 mA hg⁻¹ at a current density of 0.5 A g⁻¹, i.e., a marked improvement in rate performance and bending stability. Following 800 charge and discharge cycles at a current density of 2 A g⁻¹, the battery demonstrates an impressive capacity retention rate of approximately 90.6% along with a notable average coulombic efficiency of 98.7%, underscoring its remarkable strength and stability. The PANI/CNT/CC|CNF/PAM|Zn battery can power the device when it is bent or even folded. Such enhanced electrochemical performance of optimized ZIB is originated from synergistic coupling between the 3D cathode and CNF/PAM dual-network hydrogel electrolyte, which simultaneously facilitates electron transport, Zn²⁺ ion diffusion, and interfacial stability.