High-performance solid-state zinc-ion batteries enabled by flexible and highly Zn conductive solid-polymer electrolyte

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 11; no. 26; pp. 1475 - 1485
• Main Authors: Puttaswamy, Rangaswamy, Tian, Zhenchuan, Lee, Hyocheol, Kim, Do Youb, Le Mong, Anh, Kim, Dukjoon
• Format: Journal Article
• Published: 04.07.2023
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d3ta00133d

The utilization of solid-polymer electrolytes (SPEs) is of great interest to construct high-performance energy storage systems, owing to the high flexibility/elasticity, high thermal properties, reduced dendrite formation, suppression of cathode dissolution, and overcoming of leakage and safety issues associated with liquid electrolytes. Herein, we propose a flexible and highly Zn 2+ conductive solid-polymer electrolyte (SPE) for solid-state zinc-ion batteries. The proposed PVA-inter-PEG 30% /IL 70% SPE exhibits high Zn 2+ ionic conductivity (2.264 mS cm −1 ), low glass transition temperature ( T g = −10.2 °C), good thermal stability (>200 °C), and higher oxidation stability against zinc (∼2.8 V). Moreover, PVA-inter-PEG 30% /IL 70% SPE provides a stable interfacial contact to the zinc anode and enables dendrite-free zinc stripping/platting over 3000 h of cycling at 0.2 mA cm −2 . The solid-state Zn//V 10 O 24 · n H 2 O cell fabricated with PVA-inter-PEG 30% /IL 70% SPE delivered a discharge capacity as high as 325 mA h g −1 at 0.1 A g −1 and demonstrates good rate performance (∼325/110 mA h g −1 at 0.1/10 A g −1 , respectively) with reasonable cycling stability. Besides, the PVA-inter-PEG 30% /IL 70% SPE applied in the fabrication of a flexible pouch-cell prototype demonstrates safety performance and can serve as promising and reliable energy storage devices for flexible and wearable applications. PVA-inter-PEG 30% /IL 70% SPE not only demonstrates high Zn 2+ conductivity (2.264 mS cm −1 ), high flexibility, and high thermal stability (>200 °C), but also provides wide ESW (up to 2.8 V) and a stable interface to electrodes.