High Performance Polymer/Ionic Liquid Thermoplastic Solid Electrolyte Prepared by Solvent Free Processing for Solid State Lithium Metal Batteries

• Main Authors: Francisco González, Pilar Tiemblo, Nuria García, Oihane Garcia-Calvo, Elisabetta Fedeli, Andriy Kvasha, Idoia Urdampilleta
• Format: Article
• Language: English
• Published: MDPI AG 2018-08-01
• Series: Membranes
• Subjects: solid state battery; thermoplastic polymer electrolyte; ionic liquid; sepiolite; inorganic filler
• Online Access: http://www.mdpi.com/2077-0375/8/3/55

A polymer/ionic liquid thermoplastic solid electrolyte based on poly(ethylene oxide) (PEO), modified sepiolite (TPGS-S), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and 1-Butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR14TFSI) ionic liquid is prepared using solvent free extrusion method. Its physical-chemical, electrical, and electrochemical properties are comprehensively studied. The investigated solid electrolyte demonstrates high ionic conductivity together with excellent compatibility with lithium metal electrode. Finally, truly Li-LiFePO4 solid state coin cell with the developed thermoplastic solid electrolyte demonstrates promising electrochemical performance during cycling under 0.2 C/0.5 C protocol at 60 °C.