การพัฒนานาโนคอมพอสิตไทเทเนียมไดออกไซด์เฟสบรอนซ์สำหรับใช้เป็นวัสดุแอโนดประสิทธิภาพสูงในแบตเตอรี่ลิเทียมไอออน

Abstract

This research aimed to develop TiO2(B) anode material to improve electrochemical properties such as fast charge, cycle and rate stability, life-long time, and safety, which were more than commercial anode material. In this work, the parameters of synthesis conditions such as hydrothermal temperatures and hydrothermal times on particle size, particle morphology, and crystallinity of as-synthesized TiO2(B) nanoparticles by the hydrothermal process were studied electrochemical properties of lithium-ion battery. The as-synthesized samples were characterized by X-ray diffractometer (XRD) and Scanning electron microscope (SEM). Galvanostatic charge-discharge battery testing, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) measured the electrochemical properties of samples. The hydrothermal temperature and time influenced the morphology, crystallinity, phase formation of TiO2(B) particles and electrochemical properties in the lithium-ion battery. TiO2(B) nanorods, which were synthesized by using a hydrothermal reaction temperature of 220ºC for 12 hr had the highest specific capacity and fast charge rate of 348.8 and 207.3 mAh/g, which was operated with the current density of 100 mA/g after 100 cycles and current density 5000 mA/g after 1000 cycles, respectively. Moreover, the optimum TiO2(B) nanorods with the highest crystallinity and highest specific capacity, synthesized by hydrothermal reaction temperature of 220ºC for 12 hr, were used to fabricate new composite anode material with nano silicon on a hierarchically porous spherical carbon by sol-gel polymerization, microemulsion and carbonization under carbon dioxide atmosphere to improve high-performance in the lithium-ion battery. The amount of nano silicon and titanate were varied in synthesized composite anode material. The composite materials were studied for their physical appearances and their electrochemical property. The composite in condition 4, which was heated at 700ºC for 2 hr had good morphology of carbon sphere with well TiO2 nanorods distribution, which affected the highest specific capacity of 285.4 mAh/g for 100 cycles at a current density of 100 mA/g.