MgO-Coated Layered Cathode Oxide With Enhanced Stability for Sodium-Ion Batteries

Frontiers in Energy Research

Jinlin Lu¹  Yansheng Yin¹  Yi Zhang¹  Shuo Bao²  Ling Xue²  Ling Yan³ 

[1] Research Center for Corrosion and Erosion Process Control of Equipment and Material in Marine Harsh Environment, Guangzhou Maritime University, Guangzhou Guangdong, China;School of Materials and Metallurgy, University of Science and Technology, Liaoning, Anshan,China;State Key Laboratory of Metal Material for Marine Equipment and Application, Anshan, China;

关键词: sodium-ion battery;    layered cathode oxide materials;    MgO modification;    Na0.67Ni0.33Mn0.67O2;    electrochemical properties;   

DOI  :  10.3389/fenrg.2022.847818

来源: DOAJ

【 摘 要 】

Na0.67Ni0.33Mn0.67O2 is a prospective layered cathode material for sodium-ion batteries owing to its low cost, ease of synthesis, and high specific capacity. However, due to direct contact with electrolytes during the cycling process, the cyclic stability is not satisfied. To address this issue, magnesium oxide (MgO) surface modification was performed in this study to improve the material’s cycling properties. MgO layers of various thicknesses were successfully coated onto the cathode, and their electrochemical performances were thoroughly investigated. Among the as-prepared samples, the 2 wt% MgO-coated sample demonstrated the best rate capability and cycling stability. It had an initial reversible discharge capacity of 105 mAh g−1 in the voltage range from 2.0 to 4.5 V at 0.2 C with a high cycle retention of 81.5%. Electrochemical impedance spectroscopy (EIS) results showed that the 2 wt% MgO-coated electrode had the highest conductivity due to the smaller charge transfer resistance (Rct) value. All the test results show that the MgO modification improves the electrochemical properties of Na0.67Ni0.33Mn0.67O2 cathode material. This research could lead to the development of a promising strategy for improving the electrochemical performance of next-generation sodium-ion batteries.

【 授权许可】

Unknown