以Fe2O3为原料制备LiFePO4/C复合材料及其性能研究

以Fe2O3为铁源原料, 利用热还原法成功地制备了LiFePO4/C复合材料. 用XRD以及SEM对材料的晶体结构以及表面形貌进行了表征. 通过循环伏安和充放电测试研究了材料的电化学性能. 研究结果表明， 于700 ℃下制备的LiFePO4/C复合材料在0.1C的倍率下可以得到放电容量144.8 mA·h/g, 在循环160次后, 容量仍保持在141.4 mA·h/g. 这种以廉价的Fe2O3代替目前常用的二价铁盐原料方法, 具有减少LiFePO4合成成本的优点.

Preparation and Properties of LiFePO4/C Composite Materials with Fe2O3 as Starting Reactant

LiFePO4 was considered as a new kind of cathode material candidate for lithium ion batteries due to its advantages. LiFePO4/C composites were successfully prepared from Fe2O3 via solid state reaction by a thermal reduction method in Ar+5%(volume fraction) H2 atmosphere. The crystal structure and electrochemical behavior of the materials were investigated using XRD, SEM, CV and charge/discharge cycle measurements. Based on the results of TGA-DTA, LiFePO4/C composites were synthesized at different temperatures, and it was found that the LiFePO4/C composites synthesized at 700 ℃ with 8.76% mass fraction carbon content presented the initial discharge capacity of 144.8 mA·h/g at 0.1C, and after 160 cycles, the capacity remained as 141.4 mA·h/g. The method is available due to the low cost of Fe2O3 instead of using bivalent ferrous compound.