리튬이온배터리 응용을 위한 Organosilicon 기반 전해질 합성 및 특성 분석에 관한 연구

Abstract

Chapter 1. Synthesis and Characterization of Organosilicon based Electrolytes for Lithium-Ion Batteries Application Lithium-ion batteries (LIB) as secondary rechargeable batteries are used in various electronic devices, such as mobile phones, portable computers and others. LIB as a renewable energy in electric vehicles and energy storage system (ESS) exhibits a potential application. However, to overcome the required performance for electric vehicles and ESS, the safety and energy density issues should be solved first. To solve these problems we designed and synthesized compounds. These compounds has many advantages for safe electrolytes in lithium-ion batteries. The advantages is high flash point, high conductivity at low-temperature, non-hydrolyzable and the cycling performance test of a full cell that utilized the compounds of functionlized silane electrolyte solvents showed similar result as a reference cell in lithium-ion batteries. In order to improve the safety of energy storage devices, much effort has been devoted to developing safer electrolytes such as solid electrolytes and ionic liquids.

Chapter 2. Piezochromism and Solvatochromism Fluorescence Behavior of Benzene Derivatives In this research, we synthesized benzene derivativees and analyzed properties of Piezochromism and Solvatochromism. All the synthesized benzene derivativees have donor-ㅠ-donor structures, and we applied Triphenylamine and Phenylcarbazole with donor group. We synthesized with dimer, trimer and tetramer shapes. However, to overcome the required performance for electric vehicles and ESS, the safety and energy density issues should be solved first. All the synthesized benzene dervativees have properties of Piezochromism and Solvatochromism. In the case of Solvatochromism, we observed that as the number of donor groups increases, the wavelength shift of Photoluminescence gets longer due to polarity. In the case of Piezochromism, after we applied filter paper and pressure, we measured the changes of wavelength shift of Photoluminescence. As the results, we also observed that as the number of donor groups increases, the wavelength shift of photoluminescence affected the wavelength shift of solvatochromism, which got longer.