摘要
采用固相湿磨并热处理,以酚醛树脂为碳源,合成了锂离子电池正极材料LiMn1-xMgxPO4/C(x=0,0.01、0.04、0.05和0.1)。制备的样品具有相似的形貌,掺杂的镁离子半径较小导致了晶格收缩,从而使颗粒细小且分布均匀。充放电测试和交流阻抗表明,由于镁离子掺杂加快了电化学动力学反应过程,而明显提高了材料的电化学性能。600℃煅烧得到的LiMn0.96Mg0.04 PO4/C材料在0.05C倍率下具有144mAh/g的放电容量;高放电倍率下,以恒流-恒压-恒流模式进行充放电测试,LiMn0.96Mg0.04PO4/C复合正极材料显示出良好的循环性能及倍率性能。
LiMn1-x Mgx PO4/C（x =0,0.01,0.04,0.05,0.1） were synthesized by using wet-ballmilling and solidstate calcining with phenolic resin as the carbon source. All samples are single phase with a similar morphology, but the cation substitution results in a crystal lattice shrink because of the smaller ionic radii of Mg^2＋ , the particles are small and homogeneous. Charge/discharge and EIS measurement shows that the Mg substitution leads to a significantly increased reversible capacity due to the enhanced electrochemical kinetics. LiMn0.96- Mg0.04PO4/C calcined at 600＇C has a discharge capacity of 144mAh/g at 0.05C. When charging-discharging by CC-CV-CC mode at high rates, LiMn0.96Mg0.04PO4/C composite exhibits a good cyclahility and rate capability.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2013年第10期1381-1384,共4页
Journal of Functional Materials
基金
中央高校基本科研业务费专项资金资助项目(DUT11NY08)
