In situ polymerized quasi-solid polymer electrolytes enabling void-free interfaces for room-temperature sodium–sulfur batteries

作者：Jiafang Huang, Zhenwei Song, Junxiong Wu, Yuhui Miao, Manxian Li, Danjing Lin, Kai Zhu, Xiaochuan Chen, Xiaoyan Li, Yuming Chen · 发表于：Energy Materials and Devices · 年份：2024 · DOI：10.26599/emd.2024.9370051 · 被引用次数：14 · 研究领域：Advanced Battery Materials and Technologies

Rechargeable room-temperature Na–S (RT Na–S) batteries are promising for large-scale energy storage because of their high energy density and low cost. However, their practical viability is limited by polysulfide shuttling and Na dendrite formation. Here, a quasi-solid polymer electrolyte with dual sodium salts (DS-QSPE) was created through in situ polymerization, demonstrating high ionic conductivity (4.8×10 −4 S cm −1 at 25 °C), a high sodium-ion transference number (0.73), and effective confinement of polysulfides. Theoretical calculations confirm enhanced Na-ion transport, attributed to the strengthened coordination of anions with the poly-dioxolane chain and the increased dissociation of sodium salts, consistent with the experiment results. More importantly, the DS-QSPE forms an interconnected network structure within the sulfurized polyacrylonitrile (SPAN) cathode, providing abundant and seamless electrochemical reaction interfaces that promote efficient and uniform ion transport pathways. Consequently, the Na||SPAN battery with DS-QSPE maintains a high capacity of approximately 327.4 mAh g − 1 (based on the mass of SPAN) after 200 cycles at 0.2 A g −1 , achieving 81.4% capacity retention, which is much superior to that in liquid electrolyte counterpart. This study presents a facile approach to resolving the interfacial issue of solid-state Na–S batteries.