摘要
以乳酸镁做为Mg^(2+)的掺杂源和部分的碳源,在惰性氛围下用模板-固相合成法合成了掺Mg^(2+)的LiFePO_4/C复合正极材料,考察了Mg^(2+)对于目标化合物电化学和物理性能的影响.研究结果表明,在C/3倍率下材料掺杂前后第二个循环的放电容量分别为140.5和159.9mAh/g,循环20次后容量为140.4和162.1mAh/g.电化学交流阻抗表明,掺杂后的材料阻抗R_(ct)从180Ω减小到120Ω.掺杂后振实密度比掺杂前提高了0.229g·cm^(-3).
Stoichiometric Mg-doped LiFePO4/C cathode material was synthesized through a templatesolid state reaction in an inert atmosphere using magnesium lactate as dopant and part of carbon source. Effects of Mg2＋ doping on the electrochemical and physical performances of the cathode materials were investigated. At 1/3C discharge rate, the secondly reversible specific capacity of the Mg-doped LiFePO4/C is nearly 20mAh/g higher than that of the undoped one. After 20 cycles, the capacity of the former is 162.1mAh/g, 22mAh/g higher than that of the latter. Impedance Rct of the Mg-doped material is 120Ω, while that of the undoped material is 180Ω.The tap density of Mg-doped material is also improved by 0.229g.cm^-3 compared with undoped material.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第4期627-630,共4页
Journal of Inorganic Materials
基金
河南省重大科技攻关项目(0522020300)
