磷铁制备复合材料LiFePO_4/C的新方法研究

Study on a new synthesis mothod of LiFePO_4/C with FeP

以磷铁为原料,采用两步烧结的碳热还原法成功合成了LiFePO4材料并研究了不同时间对烧结产物的影响,该方法可以实现原料的循环利用,对环境零排放。采用XRD,恒电流充放电法,交流阻抗对样品晶型和电化学性能进行表征和研究。烧结15h的样品具有最接近标准卡片的晶型,在0.05C时的放电容量也最大可以达到162.3mAh/g。在0.5C循环15次后放电容量仍有124.6mAh/g,衰减仅为2.02%,具有良好的循环性。对比4个样品,15h烧结的样品也就有最小的反应阻抗仅为56Ω。

LiFePO4 was synthesized by a carbon thermal reduction method using FeP as the raw material and the influence of sintering time on the performance of the sample was studid.It was envrionment-friendly and raw metarials can be recycled by the method.XRD,galvanostatic charge/discharge and EIS were adopted to characterize the end-product.After sintering for 15h,the crystal of sample wasclosest to the standard card.The discharge capacity of sample sintering for 15h can reach 162.3mAh/g at 0.05C.It had still 124.6mAh/g after 15 cycles at 0.5C with 2.02% reduction.It also had the minimum impedance of the reaction just 56 ohm.