Ice-Template-Induced Highly Interconnected Porous Polymer Gel Electrolytes for Dendrite-Free Flexible Zinc–Air Batteries
Shan Cai, Xin Hao, Yuqing Luo, Guoqiang Zou, Hongshuai Hou, Jiugang Hu, Xiaobo Ji
Abstract
Improving the performance of quasi-solid-state gel polymer electrolytes is critical for addressing issues at the Zn anode–electrolyte interface of high-performance flexible Zn–air batteries (FZABs). In this study, a highly interconnected porous poly(vinyl alcohol)/poly(ethylene glycol) (PVA/PEG) hydrogel electrolyte was fabricated via an ice-crystal template for FZABs. The mechanical toughness and stability of the gel electrolytes can be reinforced by the formation of a PEG–PVA cross-linking network. The three-dimensional PVA/PEG porous skeleton greatly increased electrolyte uptake and accelerated ion transport, leading to high ionic conductivity (42.5 mS cm –1 ). In-situ synchrotron radiation X-ray imaging revealed that the PVA/PEG network can effectively inhibit dendrite growth and the hydrogen evolution reaction. The assembled FZABs exhibited superior cycle stability, high power density (109 mW cm –3 ), and excellent flexibility and structural stability under bending conditions, thus showing great potential for future applications in flexible and wearable electronic device technologies.