摘要
锂离子电池是目前综合性能最好的二次电池之一。本文采用溶剂热法制备钛酸锂纳米颗粒,系统研究了前驱体钛锂比、溶剂热温度与煅烧温度对材料结构的影响。利用X射线衍射仪(XRD)、透射电子显微镜(TEM)和恒电流充放电测试仪对尖晶石型钛酸锂的晶型、形貌结构和电化学性能进行分析。研究表明,煅烧温度对尖晶石型钛酸锂的合成起主要作用。当煅烧温度为800℃时,制得的样品粒径均一,具有较高结晶度和纯度的Li_4Ti_5O_(12)相;3C时首次放电比容量为107 m Ah/g,经过100次循环后,比容量仍达到为70 mAh/g,每次循环衰减率小于0.35%,且50个循环后库伦效率稳定并接近100%,展现出较好的大倍率充放电性能和循环稳定性能。
Lithium-ion battery is one of secondary batteries with the best comprehensive properties. In this paper,lithium titanate nanoparticles are prepared via a solvothermal method. The influences of Ti-Li ratio,solvent thermal treatment temperature,and calcination temperature on material structure are studied systematically. X-ray diffraction（XRD） analysis,transmission electron microscopy（TEM） and galvanostatic current charge-discharge test are applied to analyze the crystallinity,morphology and electrochemical performance of spinellithium titanate. It is found that the calcination temperature plays the key role to synthesis of the spinel-lithium titanate. When calcined at 800 ℃,the as-prepared samples show uniform size,high crystallinity and purity of Li4Ti5O12 phase. A specific discharge capacity is around 107 m Ah/g at a rate of 3C,and still remains 70 m Ah/g after 100 cycles,which has less than 0.35% discharge capacity loss. In addition,the coulombic efficiency is close to 100% after 50 cycles,showing good high-rate charge-discharge properties and cycle stability performance.
出处
《陶瓷学报》
CAS
北大核心
2015年第6期578-582,共5页
Journal of Ceramics
基金
青海省国际合作(2014-HZ-816)
新型陶瓷与精细工艺国家重点实验室开放基金(KF201513)
关键词
锂离子电池
尖晶石型钛酸锂
溶剂热
纳米颗粒
lithium-ion battery
spinel-lithium titanate
solvothermal method
nanoparticles
