The Investigation of Fluoro-Functionlized Benzimidazole Li Salt Electrolyte Additive in Lithium Ion Battery

• Main Authors: Jian-Hua Wu, 吳建驊
• Other Authors: Fu-Ming Wang
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/41293195676252282908

碩士 === 國立臺灣科技大學 === 應用科技研究所 === 104 === LiPF6 is widely used lithium salt, which plays a critical role in initiating electrochemical reaction in lithium ion batteries. However, LiPF6 is usually at several unreasonable surrounding such high T, high V, and high humidity. At high T, the LiPF6 suffers side reaction and forms PF5, which degrades the solid electrolyte interface (SEI) and leads the formations of LiF and HF. Due to the Lewis acid basic reaction, benzimidazole-based lithium salt (BZ) is used neutralized the PF5, which side reaction in lithium in battery. In this study, modified BZ salt additives are successfully synthesized, which is designed with the electron-withdrawing groups. In terms of the results, fluoro-modified BZ salt increases the ability of electrolyte within lithium cathode layer material. Related cyclic voltammetry, electrochemical impedance spectroscopy, charge-discharge, and cycle life are investigated. Our in-situ GC/MS analysis reveals that the fluoro-modified BZ inhibits the gas evolution from Li-rich cathode indication the electron-withdrawing groups is useful for maintain the anodic reaction of electrolyte. These materials are new, first publication for the application of high voltage lithium in battery.