【摘要】 采用高温固相法合成了LiFePO4蓄电池正极材料,并用X射线衍射、扫描电镜、循环伏安和充放电测试等方法对其晶体结构、表观形貌和电化学性能进行了研究;考察了不同负极和电解液对扣式Li-LiFePO4蓄电池电性能的影响。研究结果表明,该方法所合成的LiFePO4为单一的橄榄石型晶体结构、晶粒较细、粒径分布较均匀;以0.1 C充放电,首次放电比容量为134.8 mAh/g,50次的平均放电比容量不小于128 mAh/g,其充放电效率在99.6%以上;以锂/铝合金作负极,LiAsF6/碳酸乙烯酯(EC)+二甲基四氢呋喃(2-MeTHF)+四氢呋喃(THF)为电解液所得扣式锂蓄电池的性能最好。更多还原

【Abstract】 Lithium iron phosphate as cathode material for lithium batteries was synthesized by solid-state reaction. The crystalline structure, morphology of particles, and electrochemical performance of the sample were investigated by X-ray diffraction, scanning electron microscopy, cyclic voltammetry, and charge-discharge test, and also the effects of different anode materials and different electrolyte systems on the performance of lithium batteries were studied. The results show that LiFePO4 is simple pure olive-type phase with small particles, and uniformly distribution of gain size, and the first specific discharge capacity of which is 134.8 mAh/g charged and discharged at C/10 rate, after 50 times cycling, the average specific discharge capacity is above 128 mAh/g, and each charge-discharge cycling efficiency is above 99.6%. The coin-type Li-LiFePO4 lithium batteries possess good electrochemical performance that with Li/Al alloy as anode material and LiAsF6/EC+2-MeTHF+THF as electrolyte.更多还原