摘要
以LiOH、FeSO4和H3PO4为原料,采用水热法合成了结晶性良好的LiFePO4颗粒。在此基础上,以葡萄糖为碳源,掺入不同量的碳,形成LiFePO4/C复合材料。样品经过XRD、SEM、恒流充放电测试、EIS表征,结果表明,掺碳提高了LiFePO4的比容量、循环性能和锂离子的扩散动力学性能。电化学测试表明,LiFePO4/C放电比容量开始随着碳含量的增加而上升,随后降低。其中,3%碳含量的LiFePO4/C样品具有最佳的放电性能,0.1C倍率下达到145mAh/g,0.2C倍率下达到142mAh/g,50次循环后仅衰减0.7%。
The olivine-type LiFePO4/C cathode materials were prepared via hydrothermal reaction using LiOH, FeSO4 and H3 PO4 as raw materials and different contents of glucose as the carbon source. The samples were characterized by X-ray powder diffraction （XRD）, scanning electron microscopy （SEM）, constant current charge-discharge cycling test and and electrochemical impedance spectroscopy（EIS）. The results indicate that carbon adding improves the capacity, cycle stability and lithium ion diffusion kinetics of LiFePO4. Electrochemical tests show that the discharge capacity first increases and then decreases with the increase of carbon content. The optimal sample LiFePO4/C with 3wt% carbon exhibites the highest discharge capacity of 145mAh/g at 0. 1C rate, 142mAh/g at 0. 2C rate, after 50 cycles, capacity fade was only 0. 7%.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2011年第18期66-69,共4页
Materials Reports
基金
国家自然科学基金(20803042)
关键词
水热法
磷酸铁锂
包碳
hydrothermal reaction, LiFePO4, carbon coating
作者简介
彭行圆：男，1987年生，硕士研究生，研究方向为锂离子正极材料Tel：027—87558237E-mail：xingyuanp@163．com
黄云辉：通讯作者，男，教授Tel：027-87558241E-mail：huangyh@mail．hust．edu．cn
