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采用快速共沉淀法合成了立方体的层状无钴富锂固溶体正极材料0.6Li2MnO3-0.4LiNi0.5Mn0.5O2.通过X射线衍射(XRD),X射线光电子能谱(XPS),电感耦合等离子体(ICP),扫描电子显微镜(SEM),透射电子显微镜(TEM)及电性能测试等手段对材料进行了表征.结果表明,材料具有典型的α-Na Fe O2六方层状晶体结构且具有与目标材料相似的化学组成.SEM和TEM结果表明,材料由粒径为40–200 nm的纳米颗粒组装成立方体结构.在文中给出了一个立方团聚体可能的形成机理.电化学性能测试(2.0–4.8 V电压范围内(vs Li/Li+))显示该材料具有优异的倍率性能,0.1C和10C倍率下的放电比容量分别是243和143 m Ah g–1.此外,该材料具有良好的循环稳定性,即使在大倍率测试后,0.5C倍率下循环72次仍显示出90.7%的高容量保持率.这种具有简易操作步骤和优异结果的共沉淀方法是一种经济的能够促进锂离子电池正极材料大规模应用的技术手段.
A layered solid cobalt-free lithium-rich solid solution cathode material 0.6Li2MnO3-0.4LiNi0.5Mn0.5O2 was synthesized by rapid coprecipitation method and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrical properties testing were used to characterize the material.The results showed that the material possesses a typical hexagonal α-NaFeO2 crystal structure and possesses the same properties as the target material Similar to the chemical composition.SEM and TEM results show that the material assembled by the particle size of 40-200 nm nanoparticles into a cubic structure.In this paper, the possible formation mechanism of a cubic agglomerate electrochemical performance test (2.0-4.8 V (vs Li / Li +)) shows that the material has excellent rate capability and discharge capacities of 243 and 143 m Ah g-1 at 0.1C and 10C, respectively. In addition, the material has good cycle stability , A high capacity retention of 90.7% is still exhibited at 72 cycles at a 0.5C rate even after a large magnification test.The coprecipitation method with simple operation steps and excellent results is an economical method that can promote a lithium ion battery Cathode material Mold technology applications.