合成条件对LiFePO_4振实密度的影响

Effect of different synthesis route on tap density of LiFePO_4

以自制FePO4作为铁源烧结制备LiFePO4,并讨论烧结条件对其振实密度的影响,通过X-射线粉末衍射和电子扫描电镜对产物结构和形貌进行了表征和分析.结果表明:以自制的FePO4前躯体为铁源,碳酸锂为锂源,添加适量的葡萄糖,可以合成出高振实密度包覆碳的LiFePO4.最佳工艺条件为:FePO4与Li2CO3混合的Li∶Fe比为1.05∶1,混入质量分数10%的葡萄糖,烧结气氛为体积分数95%的高纯Ar气和体积分数5%的H2的混合气体,烧结温度为500℃恒温5 h和750℃时恒温18 h两个恒温段.在最佳工艺条件下制备的LiFePO4其振实密度可以高达2.23 g/cm3.

High-tap density LiFeP04 cathode is prepared by self-made FeP04 as Fe source and the effects of different sinter condition on its tap density are investigated.The crystal structure and morphology of products are characterized by XRD and SEM.The results show that the optimized synthesis route is：the molar ratio of Li to Fe is 1.05 to 1 ;the weight ratio of glucose is 10%;the products are sintered in Ar/H2 of 95% to 5% at 500 ℃ for 5 h and then raised to 750 ℃ and maintained for 18 h.The tap density of LiFePO4 synthesized at this optimized condition is high to 2.23 g/cm3.