钛酸锂纳米颗粒的可控制备及其电化学性能研究  

Controllable Preparation and Electrochemical Performance of Li_4Ti_5O_(12) Nanoparticles

作　　者：王亚萍[1,2] 南辉[3] 杨盼[2] 赵晓冲[2] 赖新春[2] 王刚[1] 

机构地区：[1]青海大学化工学院,青海西宁810016 [2]表面物理与化学重点实验室,四川绵阳621907 [3]青海大学机械学院,青海西宁810016

出　　处：《陶瓷学报》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)

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.

关 键 词：锂离子电池 尖晶石型钛酸锂 溶剂热 纳米颗粒 

分 类 号：TQ174.75[化学工程—陶瓷工业]