将层状的LiNi1/3Co1/3Mn1/3O2锂离子电池正极材料与尖晶石型的LiMn2O4按质量比为2∶98混合烧结,采用X射线衍射（XRD）、循环伏安法（CV）、交流阻抗（EIS）以及充放电测试研究LiMn2O4对LiNi1/3Co1/3Mn1/3O2电化学性能的影响。研究表明混...将层状的LiNi1/3Co1/3Mn1/3O2锂离子电池正极材料与尖晶石型的LiMn2O4按质量比为2∶98混合烧结,采用X射线衍射（XRD）、循环伏安法（CV）、交流阻抗（EIS）以及充放电测试研究LiMn2O4对LiNi1/3Co1/3Mn1/3O2电化学性能的影响。研究表明混合LiMn2O4有利于提高LiNi1/3Co1/3Mn1/3O2正极材料的首次库仑效率、循环性能和倍率性能,在3.0~4.3 V以1 C循环,首次放电比容量和库仑效率分别为150.3 m Ah/g和85.5%,循环50次后容量保持率为88.9%;在5 C下充放电仍保持136.2 m Ah/g。循环伏安与交流阻抗测试表明混合2%（质量分数）LiMn2O4可以提升材料的可逆性和放电容量,降低电荷转移电阻。展开更多
文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微...文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微纳颗粒进行表征,结果可知所获微纳颗粒均为橄榄石结构,而LiMn0.75Fe0.25PO4/C分散性较好,颗粒大小较均匀。与LiFePO4/C正极材料相比,LiMn0.75Fe0.25PO4/C的导电性、放电电压、循环稳定性和储锂性能均有明显提高。LiMn0.75Fe0.25PO4/C充放电电压平台为4.1V;在0.5C的电流密度下,首次放电比容量为160mA·h/g,在100圈循环后容量依然保持在140mA·h/g;在10C的电流密度下,保持了60mA·h/g的容量。该文对于研究和发展新型可替代LiFePO4的锂离子电池正极材料具有重要的意义。展开更多
Lithium iron phosphate （LiFePO4）/lithium manganese phosphate （LiMnPO4）-positive material was suc- cessfully prepared through ball milling and high-temperature sintering using manganese acetate, lithium hydroxide, ...Lithium iron phosphate （LiFePO4）/lithium manganese phosphate （LiMnPO4）-positive material was suc- cessfully prepared through ball milling and high-temperature sintering using manganese acetate, lithium hydroxide, ammonium dihydrogen phosphate, and ferrous oxalate as raw materials. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, scanning elec- tron microscopy, a constant current charge-discharge test, cyclic voltammetry, and electrochemical impedance spectroscopy. The effects of lithium iron phosphate coating were also discussed. Because of its special core-shell structure, the as-prepared LiMn0.TFe0.3PO4-LiFeP04-C exhibits excellent electro- chemical performance. The discharge capacity reached 136.6 mAh/g and the specific discharge energy reached 506.9 Wh/kg at a rate of 0.1 C.展开更多
文摘将层状的LiNi1/3Co1/3Mn1/3O2锂离子电池正极材料与尖晶石型的LiMn2O4按质量比为2∶98混合烧结,采用X射线衍射（XRD）、循环伏安法（CV）、交流阻抗（EIS）以及充放电测试研究LiMn2O4对LiNi1/3Co1/3Mn1/3O2电化学性能的影响。研究表明混合LiMn2O4有利于提高LiNi1/3Co1/3Mn1/3O2正极材料的首次库仑效率、循环性能和倍率性能,在3.0~4.3 V以1 C循环,首次放电比容量和库仑效率分别为150.3 m Ah/g和85.5%,循环50次后容量保持率为88.9%;在5 C下充放电仍保持136.2 m Ah/g。循环伏安与交流阻抗测试表明混合2%（质量分数）LiMn2O4可以提升材料的可逆性和放电容量,降低电荷转移电阻。
文摘文章首先采用溶剂热法合成了系列LiMn1-xFexPO4(x=0.15、0.25、0.35、0.45)微纳颗粒,随后采用热分解的方法对微纳颗粒进行碳包覆处理。采用X射线衍射仪(X-ray diffraction,XRD)和扫描电子显微镜(scanning electron microscope,SEM)对微纳颗粒进行表征,结果可知所获微纳颗粒均为橄榄石结构,而LiMn0.75Fe0.25PO4/C分散性较好,颗粒大小较均匀。与LiFePO4/C正极材料相比,LiMn0.75Fe0.25PO4/C的导电性、放电电压、循环稳定性和储锂性能均有明显提高。LiMn0.75Fe0.25PO4/C充放电电压平台为4.1V;在0.5C的电流密度下,首次放电比容量为160mA·h/g,在100圈循环后容量依然保持在140mA·h/g;在10C的电流密度下,保持了60mA·h/g的容量。该文对于研究和发展新型可替代LiFePO4的锂离子电池正极材料具有重要的意义。
基金Financial support from the Knowledge Innovation Program of the Chinese Academy of Sciences （Grant No. KGCX2-YW-341） and the National Natural Science Foundation of China （Grant Nos. 21376247, 21573240） is gratefully acknowledged.
文摘Lithium iron phosphate （LiFePO4）/lithium manganese phosphate （LiMnPO4）-positive material was suc- cessfully prepared through ball milling and high-temperature sintering using manganese acetate, lithium hydroxide, ammonium dihydrogen phosphate, and ferrous oxalate as raw materials. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, scanning elec- tron microscopy, a constant current charge-discharge test, cyclic voltammetry, and electrochemical impedance spectroscopy. The effects of lithium iron phosphate coating were also discussed. Because of its special core-shell structure, the as-prepared LiMn0.TFe0.3PO4-LiFeP04-C exhibits excellent electro- chemical performance. The discharge capacity reached 136.6 mAh/g and the specific discharge energy reached 506.9 Wh/kg at a rate of 0.1 C.
