LiNi0.5Mn1.5O4 was synthesized with industrial Li2CO3,Ni2O3,and electrolytic MnO2 as raw materials.The influence of calcination temperature on material performance was studied.The structure,morphology,particle size,and electrochemical properties of the particles were characterized by X-ray diffraction,scanning electron microscopy,laser particle size,discharge cycles,cyclic voltammetry,and AC impedance,respectively.The results showed that the synthetic materials were all spinel structure,but contained the impurity phase LixNi1-xO,LixNiyMnzO,or NixO.The conditions for the best structure morphology and electrochemical properties of material were synthesized at 850 ℃ for 12 h.At the rates of 1C,2C,and 5C,the initial discharge special capacity were 120.8,118.1,and 111.2 mA.h/g respectively,and the material had an excellent capacity retention after 200 cycles.%采用工业级碳酸锂、三氧化二镍和电解二氧化锰为原料合成了镍锰酸锂(LiNi0.sMnLsO4),研究了煅烧温度对材料性能的影响.采用X射线衍射、扫描电镜、激光粒度仪、放电循环曲线、循环伏安曲线和交流阻抗谱图表征了颗粒的结构、形貌、粒度分布和电化学性能.结果表明:制备的5V镍锰酸锂均为尖晶石结构,但含有杂质相LixNi14O、LixNiyMnzO和NixO.在煅烧温度为850℃、煅烧时间为12h条件下制备的样品具有最佳的结构形貌和电化学性能,在放电倍率为1C、2C、5C条件下,LiNi0.5Mn1.5O4对应的首次放电容量分别为120.8、118.1、111.2 mA· h/g,且循环200次仍具有优异的容量保持率.
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