富锂层状氧化物材料具有较高的比容量,被认为是下一代先进锂离子电池正极材料。采用丙烯酸热聚合法和柠檬酸溶胶-凝胶法分别合成了纳米富锂锰基正极材料Li1.2Mn0.54Ni0.13Co0.13O2,并进行Mg2+掺杂改性。通过扫描电子显微镜、X射线粉末衍射仪对制备的正极材料进行形貌和结构表征,并组装成纽扣电池进行充放电性能测试和电化学阻抗谱分析。结果表明,丙烯酸热聚合法合成的正极材料粒径均匀,结晶度更高;与未掺杂样品相比,掺杂Mg2+的正极材料首次库伦效率从67.66％提高到73.34％,循环性能显著改善。
Lithium-rich layered oxides material are considered to be the next generation of advanced lithium-ion battery cathode materials due to their high specific capacity.In this paper,the nano lithium-rich manganese-based cathode material Li1.2Mn0.54Ni0.13Mg0.05Co0.08O2 was synthesized by acrylic acid thermal polymerization method and citric acid sol-gel method,respectively,and modified by Mg2+-doping.Scanning electron microscopy and X-ray powder diffractometer were used to characterize the morphology and structure of the prepared cathode material,and button cells were assembled for charge-discharge performance testing and electrochemical impedance spectroscopy analysis.The analysis results showed that the cathode material synthesized by acrylic acid thermal polymerization had uniform particle size and higher crystallinity.Compared with the undoped sample,the first coulombic efficiency the Mg2+-doped cathode material increased from 67.66% to 73.34%,and the cycling performance was significantly improved.
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基金资助
2022年度河南工程学院校级一流本科课程(2022YLKCX04);2021年度河南省重点研发与推广专项(科技攻关)(212102210215);2021年度河南工程学院科研培育基金(PYXM202101)
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