Robust and high thermal-stable composite polymer electrolyte reinforced by PI nanofiber network
Qi Wang, Boheng Yuan, Yafei Lu, Fei Shen, Bin Zhao, Xiaogang Han
Abstract
Abstract To address the flammable and chemical unstable problems of liquid electrolyte, the solid electrolyte is a promising candidate to replace liquid electrolyte for solid-state batteries. Herein, a composite polymer electrolyte (CPE) of 3D polyimide (PI)-nanofiber membrane-incorporated polyethylene oxide (PEO)/lithium bis (triflu-romethanesulphonyl) imid (LiTFSI) is reported. Three advantages of the PI nanofiber network in the CPE include providing a continuous, rapid transport channel of lithium ions to improve the Li-ion conductivity, improving the mechanical properties and stability, and effectively inhibiting the dendrite growth of Li metal. The PI/PEO/LiTFSI CPE delivers an ionic conductivity of 4.2 × 10 −4 S cm −1 at 60 °C, a wider electrochemical window to 5.4 V, and an excellent thermal stability, which result in the excellent electrochemical performance of LiFePO 4 full cells assembled with PI/PEO/LiTFSI CPE.