Solid composite electrolytes with synergistic effect of various components for high voltage solid-state lithium batteries at room temperature

• Main Author: Wu, Qiqi
• Other Authors: Chen, Xiaodong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Materials
• Online Access: https://hdl.handle.net/10356/147905
• Institution: Nanyang Technological University

The need for developing all-solid-state lithium batteries has emerged, with the advancement in the electric vehicles and electronic devices. All-solid-state lithium batteries exhibit strong potential to replace the traditional lithium batteries with liquid electrolytes, due to their light weight, long cycle life, high operating voltage, and high energy density. In this study, an engineering solid electrolyte with high ionic conductivity and outstanding interfacial compatibility with electrodes has been fabricated. The results indicate that such approach enables lithium batteries with practically useful levels of functionality and promising applications that require outstanding performance at room temperature and a wide electrochemical window, such as storage systems for smart grids. In this study, Poly(acrylonitrile-co-methyl acrylate) (P(AN-MA)) solid electrolyte membrane was prepared by the simple solution casting method. The composition of the P(AN-MA) based solid electrolyte can be written as P(AN-MA) + Bis(trifluoromethane)sulfonimide lithium salt (LiTFSI) + Al_2 O_3 + Succinonitrile (SN). We performed material characterization on the composite solid-state electrolyte to reveal the microstructure and morphology of the prepared membrane. We examined the electrochemical performance of the fabricated LCO/Li cell, which demonstrates stable cycling endurance with a high ionic conductivity and a wide electrochemical window at ambient temperature. The fabricated electrolyte membrane in this experiment demonstrates the outstanding mechanical and electrical properties of inorganic ceramic electrolytes and the flexibility and interfacial compatibility of the organic polymer electrolytes. The fabricated composite solid-state electrolyte provides prominent advantages to the lithium batteries in the existing forms. This study opens up possibilities in developing high-performance lithium batteries which are essential for the energy conversion and storage systems in the future.