摘要
以Li_(2)CO_(3),TiO_(2)为原料,无水乙醇为分散剂,采用高温固相法,通过两步煅烧方式制备出不同煅烧温度下的Li_(4)Ti_(5)O_(12)粉末材料.采用X射线衍射(XRD)、扫描电镜(SEM)表征材料的结构和形貌,采用恒电流充放电、交流阻抗和循环伏安等方法测试材料电化学性能.结果表明:在800℃下煅烧6 h后可得到晶型完整的纯相Li_(4)Ti_(5)O_(12),其颗粒均匀分布在200~400 nm.Li_(4)Ti_(5)O_(12)在0.5C倍率下首次可逆比容量为157.67 mA·h/g,库伦效率为96.1%,经过100次循环充放电后容量保持率为98.63%;在5C倍率下首次可逆比容量为107.0 mA·h/g,经过1000次循环充放电后容量保持率为84.1%.
Li_(4)Ti_(5)O_(12) powders were prepared by solid-state reaction and two-step calcination method with Li_(2)CO_(3) and TiO_(2) as starting materials and anhydrous ethanol as dispersant.The microstructure and morphology of the materials were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM).The electrochemical properties of the materials were tested by constant current charge-discharge,AC impedance and cyclic voltammetry.The results show that the pure phase Li_(4)Ti_(5)O_(12) with complete crystal structure could be synthesized after calcination at 800℃for 6h,and uniform dispersion with particle size of 200~400 nm.The first reversible specific capacity of the Li_(4)Ti_(5)O_(12) sample was 157.67 mA·h/g at the rate of 0.5 C,and the coulombic efficiency was 96.1%,the capacity retention was 94.3%after 100 cycles.The first reversible specific capacity was 107.0 mA·h/g at the rate of 0.5C,the coulombic efficiency was 96.1%and capacity retention was 84.1%after 1000 cycles.
作者
龙芮涞
吴显明
吴秀婷
尹偲硕
LONG Ruilai;WU Xianming;WU Xiuting;YIN Caishuo(College of Chemistry and Chemical Engineering,Jishou University,Jishou 416000,Hunan China)
出处
《吉首大学学报（自然科学版）》
CAS
2022年第3期72-78,共7页
Journal of Jishou University(Natural Sciences Edition)
基金
国家自然科学基金资助项目(51762016)。
关键词
固相法
钛酸锂
锂离子电池
负极材料
solid-state method
Lithium titanate
Li-ion battery
anode material
