Zhao Lanqing, Hou Minjie, Ren Kun, Yang Dongrong, Li Fupeng, Yang Xiecheng, Zhou Yingjie, Zhang Da, Liu Shan, Lei Yong, Liang Feng
Key Laboratory for Nonferrous Vacuum Metallurgy of Yunnan Province, Kunming University of Science and Technology, Kunming, 650093, China.
National Engineering Research Center of Vacuum Metallurgy, Kunming University of Science and Technology, Kunming, 650093, China.
Small Methods. 2024 Oct;8(10):e2301579. doi: 10.1002/smtd.202301579. Epub 2024 Mar 3.
Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) are widely utilized in all-solid-state sodium metal batteries (ASSSMBs) due to their excellent flexibility and safety. However, poor ionic conductivity and mechanical strength limit its development. In this work, an emerging solvent-free hot-pressing method is used to prepare mechanically robust PEO-based SPE, while sodium superionic conductors NaZrSiPO (NZSP) and NaClO are introduced to improve ionic conductivity. The as-prepared electrolyte exhibits a high ionic conductivity of 4.42 × 10 S cm and a suitable electrochemical stability window (4.5 V vs Na/Na). Furthermore, the SPE enables intimate contact with the electrode. The Na||NaV(PO)@C ASSSMB delivers a high-capacity retention of 97.1% after 100 cycles at 0.5 C and 60 °C, and exhibits excellent Coulombic efficiency (CE) (close to 100%). The ASSSMB with the 20 µm thick electrolyte also demonstrates excellent cyclic stability. This study provides a promising strategy for designing stable polymer-ceramic composite electrolyte membranes through hot-pressing to realize high-energy-density sodium metal batteries.
基于聚环氧乙烷（PEO）的固体聚合物电解质（SPEs）因其出色的柔韧性和安全性而被广泛应用于全固态钠金属电池（ASSSMBs）。然而，离子电导率差和机械强度低限制了其发展。在这项工作中，采用一种新兴的无溶剂热压法制备机械性能强劲的基于PEO的SPE，同时引入钠超离子导体NaZrSiPO（NZSP）和NaClO以提高离子电导率。所制备的电解质表现出4.42×10 S cm的高离子电导率和合适的电化学稳定窗口（相对于Na/Na为4.5 V）。此外，该SPE能与电极紧密接触。Na||NaV(PO)@C全固态钠金属电池在0.5 C和60°C下循环100次后具有97.1%的高容量保持率，并表现出优异的库仑效率（CE）（接近100%）。具有20 µm厚电解质的全固态钠金属电池也展示出优异的循环稳定性。本研究为通过热压设计稳定的聚合物-陶瓷复合电解质膜以实现高能量密度钠金属电池提供了一种有前景的策略。
