以 Li2 CO3、MnO2、NiO、FeC2 O4·2 H 2 O 为原料,用高温固相法合成了尖晶石结构的 LiNi0.5 Mn1.5 O4/LiNi0.5 Mn1.45 Fe0.05 O4锂离子电池正极材料；并对合成的样品进行 XRD、SEM 及电化学性能测试。结果表明：引入Fe3+可以提高材料的结构稳定性,并且改善了材料的导电性,一定程度上减缓材料的容量衰减,LiNi0.5 Mn1.45 Fe0.05 O4表现出较好的电化学性能,0.2C 倍率下经20次充放电循环,未掺杂样品与掺杂样品的放电比容量分别为115.4 mAh/g 和120.1 mAh/g,容量保持率由92.1%提高到96.5%。
Li-ion battery cathode materials LiNi0.5 Mn1 .5 O4/LiNi0.5 Mn1 .45 Fe0.05 O4 were synthesized by high temperature solid-phase method,while Li2 CO3 ,MnO2 ,NiO and FeC2 O4 ·2 H 2 O was used as raw materials.The syn-thesized samples were tested by XRD,SEM and electrochemical measurement.Results showed:LiNi0.5 Mn1 .45 Fe0.05 O4 exhibited better electrochemical performance.When Fe doping is applied on LiNi0.5 Mn1 .5 O4 ,not only was the stability of electrode structure improved,but also its electric conductivity and cycle performance were excellent.After 20 charge-discharge cycles(at 0.2C rates),the discharge capacity of LiNi0.5 Mn1 .5 O4 was 1 1 5.4 mAh/g,while the LiNi0.5-Mn1 .45 Fe0.05 O4 was 120.1 mAh/g,with a capacity retain ratio from 92.1% to 96.5%.
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