摘要
以乙酸锂、乙酸镍、乙酸锰为原料,采用乙二醇辅助溶胶凝胶法合成了高电压LiNi_(0.5)Mn_(1.5)O_4正极材料。通过X射线衍射(XRD)、红外光谱(FT-IR)、扫描电镜(SEM)对样品进行表征,用充放电测试和电化学阻抗对LiNi_(0.5)Mn_(1.5)O_4样品进行电化学性能测试。结果表明,LiNi_(0.5)Mn_(1.5)O_4样品都具有Fd3m尖晶石结构,且无明显杂质相,样品在900℃分别烧结2 h、6 h和10 h后,在1C下首次放电比容量分别为123、137和124 m Ah/g,循环230次后的容量保持率分别为92%、98%和96%。其中900℃烧结6 h样品电化学性能最佳,4C充电8C放电,循环500次后容量依然保持在125 m Ah/g,容量保持率为94%。
A high-voltage cathode material（LiNi0.5Mn1.5O4） was synthesized by ethylene glycol-assisted sol-gel method using CH3COOLi,Mn（CH3COO）2·4H2O and Ni（CH3COO）2·4H2O as raw materials.The sample was characterized by XRD,FT-IR and SEM.The electrochemical performance of LiNi0.5Mn1.5O4 was investigated by charge-discharge testing and electrochemical impedance spectroscopy.Results indicated that the LiNi0.5Mn1.5O4 sample was of Fd3m spinel structure without any impurity phase.The sample,calcined at 900 ℃ for 2 h,6 h,10 h,respectively,showed initial discharge capacities of 123 m Ah/g,137 m Ah/g and 124 m Ah/g respectively at 1C and capacity retention rates of 92%,98% and 96% respectively after 230 cycles.The sample calcined at 900 ℃ for 6 h exhibited the best electrochemical properties,with discharge capacity remaining at 125 mAh/g after 500 cycles of 4C charge-8C discharge,and capacity retention rate at 94%.
出处
《矿冶工程》
CSCD
北大核心
2017年第4期104-107,111,共5页
Mining and Metallurgical Engineering
基金
国家自然科学基金(21473042
51364004)
广西科学研究与技术开发计划(20150106-3)
