【摘要】 以Fe（NO₃）₃·9H₂O、LiNO₃、NH₄H₂PO₄为原料,以蔗糖为碳源,以草酸为配位剂和还原剂,通过溶胶-凝胶法制备了LiFePO₄/C复合材料.应用TG、XRD、SEM等手段对材料的结构和形貌进行了表征,并通过CV、EIS和恒流充放电测试研究了材料的电化学性能.结果表明,550℃时即可得到LiFePO₄晶体材料;而600℃时制得的LiFePO₄粒径细小且分布均匀,粒径在200～400 nm之间;该材料在0.1 C和1 C放电倍率下首次放电比容量分别为161、145 mAh/g,10 C时达到108 mAh/g.更多还原

【Abstract】 LiFePO₄/C cathode material was synthesized with a sol-gel method,using Fe （NO₃）₃·9H₂O,LiNO₃ and NH₄H₂PO₄ as reactant,sucrose as carbon resource and oxalic acid as both complexant and reductant.The samples were characterized by thermal gravity（TG）, X-ray diffraction（XRD） and scanning electron microscopy（SEM）.The electrochemical performances were investigated by cyclic voltametry（CV）,electrochemical impedance spectroscopy （EIS） and galvanostatic charge/discharge.The results indicated that LiFePO₄ crystal was obtained at rather low temperature 550℃,and the particle size was uniform at 600℃, with a particle distribution from 200 to 400 nm.The as-synthesized material displayed as high first discharge capacity as 161,145 and 108 mAh/g at 0.1,1 and 10 C rates,respectively.更多还原