A Two-Step Surface Modification Optimization for Performance Recovery of NaNi 0.33 Fe 0.33 Mn 0.33 O 2

• Published in: Journal of the Electrochemical Society 2024-04, Vol.171 (4), p.40528
• Main Authors: Rong, Wenyi, He, Kepiao, Xiong, Yonglian, Yi, Ting, Hou, Quanhui, Li, Chunsheng, Sun, Yan
• Format: Article
• Language: English
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/ad3ad3

Due to its excellent electrochemical performance, O3-type NaNi 0.33 Fe 0.33 Mn 0.33 O 2 (NFM) is one of the most promising cathode materials for sodium ion. However, its poor air stability has limited the industrialization process. In this work, a low-temperature two-step method which included carbon doping and acid treatment was used to improve the electrochemical property of the air-aged NaNi 0.33 Fe 0.33 Mn 0.33 O 2. X-ray diffraction results indicated that the structure of modified NFM (NFM-M) has good crystal structure stability. NFM-M, NFM-48H (NFM after air ageing of 48 h) and fresh NFM possessed a discharge capacity of 95.25, 74.92, and 100.79 mAh·g −1 in the first cycle, respectively. The modified sample exhibits outstanding cycling stability, with a capacity retention of 90.15% after 100 cycles at 0.1 C rate. Moreover, the NFM-M sample delivers excellent rate capability with improved capacity retention of 66.9% at 2.0 C rate.