摘要
以过渡金属乙酸盐和乙酸锂为原料,柠檬酸为螯合剂,通过溶胶-凝胶法结合高温煅烧法制备了锂离子电池富锂锰基正极材料xLi2MnO3·(1-x)Li[Ni1/3Mn1/3Co1/3]O2,采用X射线衍射(XRD),扫描电子显微镜(SEM)和电化学性能测试对所得样品的结构,形貌及电化学性能进行了表征.结果表明:x=0.5时,在900°C下煅烧12h得到颗粒均匀细小的层状xLi2MnO3·(1-x)Li[Ni1/3Mn1/3Co1/3]O2材料,并具有良好的电化学性能,在室温下以20mA·g-1的电流密度充放电,2.0-4.8V电位范围内首次放电比容量高达260.0mAh·g-1,循环40次后放电比容量为244.7mAh·g-1,容量保持率为94.12%.
The lithium rich cathode materials xLi2MnO3·(1-x)Li[Ni1/3Mn1/3Co1/3]O2 (x=0.4,0.5,0.6)were successfully synthesized via sol-gel method with calcination in air.The transition metal acetate,lithium acetate,and citric acid were used as raw materials.The as-prepared materials were characterized by X-ray diffraction(XRD),scaning electron microscopy(SEM),and electrochemical tests.The material 0.5Li2MnO3·0.5LiNi1/3Mn1/3Co1/3]O2 ,which was obtained after calcination at 900°C for 12 h,exhibited fine microstructures and good electrochemical performance.When cycled at 2.0-4.8 V with a current density of 20 mA·g^-1 at room temperature,0.5Li2MnO3·0.5LiNi1/3Mn1/3Co1/3]O2 delivered a initial discharge specific capacity of 260.0 mAh·g^-1 ,and maintained a capacity of 244.7 mAh·g^-1 after 40 cycles(capacity retention 94.12%).
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2012年第4期823-830,共8页
Acta Physico-Chimica Sinica
基金
国家重点基础研究发展规划(973)(2009CB220100)
国家自然科学基金(51102018)
国家高技术研究发展计划(863)(SQ2010AA1123116001)资助项目~~
关键词
锂离子电池
溶胶-凝胶
固溶体
正极材料
电化学性能
Lithium-ion battery
Sol-gel
Solid solution
Cathode material
Electrochemical performance