采用共沉淀法合成富锂材料,并且对富锂材料进行橄榄似的包覆。通过X射线衍射仪、扫描电镜对包覆前后的富锂材料进行晶体结构和形态的观察,研究橄榄石包覆后富锂材料的电化学性能。结果表明:橄榄石包覆后对富锂材料晶体结构没有影响,并且包覆橄榄石的富锂材料表面比较光滑。另外,对橄榄石包覆后的富锂材料进行电化学性能测试,其循环稳定性、电压稳定性、阻抗测试都有明显的提升。
The Li-rich material was synthesized by a co-precipitation method,and covered the material with an olive-like coating.The crystal structure and morphology of the materials before and after coating were observed by X-ray diffractometer and scanning electron microscope,and studied the electrochemical property of the coated lithium-rich material.The results shown that coating had no effect on the crystal structure,and the surface of the material coated with olivine was smooth.In addition,the electrochemical performance test of the material after olivine coating shown that the cycle stability,voltage stability,and impedance test of the material after olivine coating all had improved significantly.
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基金资助
青海省科技厅应用基础研究项目(2017-ZJ-750)