锂离子电池正极材料LiFePO_4掺碳纳米管的性能研究

Electro-chemical Characteristics of CNTs-doped LiFePO_4 for Cathode Materials of Li-ion Battery

以Li2CO3、FeSO4.7H2O、(NH4)2HPO4和Na2EDTA为原料,掺杂碳纳米管采用水热法合成了锂离子电池正极材料LiFePO4。研究了表面活性剂和碳纳米管对产物形貌和电化学性能的影响。结果表明:LiFePO4/MWCNTs样品属于橄榄石结构,在0.1C、3.0～4.3 V条件下的首次放电比容量为145 mAh.g-1,第20次循环的比容量为144.3 mAh.g-1。

CNTs-doped LiFePO4 was synthesized by hydrothermal method using Li2CO3,FeSO4·7H2O,（NH4）2HPO4 and Na2EDTA as raw materials.The effects of surfactant and CNTs on the morphology and electrochemical performance of the samples were investigated.The results show that LiFePO4/MWCNTs has a single ordered olivine structure and its initial specific discharge capacity is 145 mAh·g-1,the specific capacity at the 20 th cycle is 144.3 mAh·g-1,in the voltage range of 3.0～4.3 V when charge-discharge at 0.1C.