核/壳纳米LiFePO_4/C正极材料的制备及其性能  

Synthesis and characterization of core-shell nano-LiFePO_4/C cathode material

作　　者：罗国恩[1] 余仕禧[1] 邵丹[1] 肖建材[1] 禹筱元[1,2] 

机构地区：[1]华南农业大学理学院生物材料研究所,广东广州510642 [2]中国科学院可再生能源与天然气水合物重点实验室,广东广州510640

出　　处：《中南大学学报（自然科学版）》2011年第7期1942-1946,共5页Journal of Central South University:Science and Technology

基　　金：广东省自然科学基金资助项目(9151064201000039);广东省科技计划项目(2009B010900025);华南农业大学"211工程"三期重点建设项目(2009B010100001);华南农业大学新学科扶持基金资助项目(K09140);中国科学院可再生能源与天然气水合物重点实验室开放基金资助项目(Y007K2)

摘　　要：采用原位聚合控制结晶法,Fe3+既为沉淀剂又为聚合反应的催化剂,在FePO4核外聚合聚吡咯合成纳米FePO4/PPy前躯体。以FePO4/PPy为铁源,葡萄糖为碳源,高温热处理制备核/壳纳米LiFePO4/C锂离子电池正极材料。并结合X线衍射、扫描电子显微镜、透射电子显微镜、拉曼光谱和充放电测试、循环伏安等手段对合成材料的结构、形貌和电化学性能进行表征。研究结果表明:在FePO4核外聚合PPy能有效抑制LiFePO4颗粒的生长,制得核/壳型纳米LiFePO4/C正极材料;该材料具有良好的电化学性能,在0.1C,0.2C,0.5C和1.0C倍率下的放电比容量分别为149,143,133和129 mA.h/g,且循环性能优异。FePO4/PPy nano-precursor was prepared by an in situ polymerization restriction method to form a polypyrrole shell on the surface of FePO4,using Fe3＋ as both precipitator and oxidant.LiFePO4/C cathode material for lithium ion battery was synthesized using FePO4/PPy as ferrous source,and glucose as carbon source.The structure,morphology and electrochemical properties of LiFePO4/C were characterized by X-ray diffraction（XRD）,scanning electronic morphology（SEM）,transmission electronic morphology（TEM）,Raman spectroscopy measurements,galvanostatic charge-discharge tests and cyclic voltammetry（CV）.The results show that the polypyrrole shell of FePO4 can effectively restrict the crystallite growth of LiFePO4 particles and obtain core-shell nano-LiFePO4/C cathode material.The electrochemical test results show that the LiFePO4/C cathode material delivers an initial discharge capacity of 149,143,133 and 129 mA？h/g at 0.1C,0.2C,0.5C and 1.0C,respectively,and has an excellent cycle performance.

关 键 词：锂离子电池 正极材料 LIFEPO4 纳米材料 控制结晶法 

分 类 号：TM912.9[电气工程—电力电子与电力传动]