应用液相沉淀法-固相烧结法制备高密度的LiFePO4/C及纯相LiFePO4.X射线衍射、扫描电镜、傅立叶红外光谱仪、电化学性能测试表明:该样品具有单一的橄榄石结构和3.4 V左右的放电平台,掺碳的LiFe-PO4具有更优良的性能,粒度较小粒径分布均匀,振实密度达1.46 g/cm3,0.1C首次放电比容量为144.6mAh/g,循环20次后容量保持率为93.2%,1C倍率首次放电比容量为133.5 mAh/g,循环20次后容量下降8.76%.
Carbon-doped LiFePO4/C and pure phase LiFePO4 cathode materials were prepared by liquid-state precipitation reaction.The results of XRD,SEM,elemental analysis,FTIR and A.C.impedance tests show that the samples have had olivine structure and a 3.4V discharge platform.The tapped density of LiFePO4/C sample could reach 1.46g/cm3,the initiate discharge capacity is 144.6mAh/g at 0.1C,which remained capacity is 93.2% after 20 cycles.The first discharge capacity is 133.5mAh/g at 1C and the capacity decreased 8.76% after 20 cycles.
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