作　　者： (王力臻）; (江庆）; (高可政）; (方华）;

机构地区： 郑州轻工业学院材料与化学工程学院,河南郑州450002 河南省表界面科学重点实验室,河南郑州450002

出　　处： 《电池》 2017年第4期193-195,共3页

摘　　要： 通过超高压处理溶胶-凝胶前驱体,以高温固相法制备磷酸铁锂(LiFePO_4)/C。用恒流充放电、循环伏安和交流阻抗等方法研究产物的电化学性能,并进行XRD、SEM等分析。超高压处理并没有改变LiFePO_4材料的晶体结构和充放电反应机理。与未经超高压处理的前驱体相比,超高压预处理的前驱体制备的材料粒径减小,均匀性提高,0.1 C首次放电容量达148.47 mAh/g、在平台电压范围内的放电容量增加约16.3 mAh/g,经过不同倍率共40次循环,容量保持率达98.2%,且倍率放电性能得到提高,欧姆阻抗和电化学反应阻抗减小。 After a ultrahigh-pressure treating to the precursor prepared by sol-gel method,lithium iron phosphate（ LiFePO_4）/C was prepared by high temperature solid state method. The electrochemical performance of product was studied by galvanostatic charge/discharge test,cyclic voltammetry and A. C. impedance. The structural and morphology were analyzed by XRD and SEM. Ultrahighpressure treatment did not change the crystal structure and charge-discharge reaction mechanism of LiFePO_4. The particle size of target material prepared by ultrahigh-pressure treatment precursor was decreased and particle uniformity improved compared with the precursor without ultrahigh-pressure treatment. The initial specific capacity reached 148. 47 mAh/g at rate of 0. 1 C,increased by 16. 3 mAh/g at the range of platform voltage. After 40 cycles at different rates,the capacity retention rate was 98. 2% and rate capability improved. Ohmic resistance and electrochemical reaction impedance decreased.

关 键 词： 锂离子电池 正极材料 磷酸铁锂 超高压处理