| 引用本文: | 任宁,卢世刚.球形LiMn1.5Ni0.5O4材料的嵌脱动力学[J].哈尔滨工业大学学报,2016,48(8):166.DOI:10.11918/j.issn.0367-6234.2016.08.028 |
| REN Ning,LU Shigang.Insertion-extraction kinetic of spherical LiMn1.5Ni0.5O4 material[J].Journal of Harbin Institute of Technology,2016,48(8):166.DOI:10.11918/j.issn.0367-6234.2016.08.028 |
|
| 摘要: |
| 为明晰LiMn1.5Ni0.5O4正极材料的动力学性能，采用水热辅助共沉淀法合成了尖晶石LiMn1.5Ni0.5O4正极材料，并采用扫描电镜(SEM)、X射线粉末衍射(XRD)和电化学阻抗(EIS)研究了材料的结构和锂离子嵌脱动力学.实验结果表明：共沉淀法制备的LiNi0.5Mn1.5O4材料颗粒呈均匀球形，且平均粒径较小，粒度分布较窄.在循环过程中，LiNi0.5Mn1.5O4的电荷转移电阻增大，锂离子扩散系数减小，进而电子电导率和离子电导率下降.温度升高后，LiNi0.5Mn1.5O4材料的溶液电阻变化不大，但是电荷转移电阻逐渐增大，锂离子扩散系数逐渐减小；此外，随着温度的升高，LiNi0.5Mn1.5O4材料的溶解速度加快，从而导致SEI膜的厚度增大.LiNi0.5Mn1.5O4材料的嵌脱锂动力学与温度和循环次数有密切关系.
|
| 关键词: 锂离子电池 正极材料 LiNi0.5Mn1.5O4 动力学性能 |
| DOI：10.11918/j.issn.0367-6234.2016.08.028 |
| 分类号:TM912.1 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(51302017) |
|
| Insertion-extraction kinetic of spherical LiMn1.5Ni0.5O4 material |
|
REN Ning, LU Shigang
|
|
（General Research Institute for Nonferrous Metals, Beijing 100088, China）
|
| Abstract: |
| To figure out kinetic performance of LiMn1.5Ni0.5O4 positive-electrode material, spinel LiMn1.5Ni0.5O4 positive-electrode materials were prepared by a hydrothermal-assisted coprecipitation method. The structure and lithium ion insertion-extraction kinetic of the material were investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The results showed that LiMn1.5Ni0.5O4 material powders prepared by coprecipitation method had a spherical morphology, a small particle size and narrow particle size distribution. During cycling of LiNi0.5Mn1.5O4, the transfer resistance increased the diffusion coefficient of lithium-ion decreased, and then the electronic conductivity and ionic conductivity reduced. After the temperature rose, the solution resistance for LiNi0.5Mn1.5O4 material changed a little, but the transfer resistance gradually increased and the diffusion coefficient of lithium-ion gradually decreased. In addition, the dissolution rate of LiNi0.5Mn1.5O4 material was accelerated, and the thickness of solid electrolyte interphase (SEI) layer extended. The insertion-extraction kinetic of LiMn1.5Ni0.5O4 material had a close relationship with temperature and cycle times.
|
| Key words: lithium ion battery positive-electrode material LiNi0.5Mn1.5O4 kinetic performance |
