Surface engineering of P2-type cathode material targeting long-cycling and high-rate sodium-ion batteries

• Published in: Journal of energy chemistry 2024-10, Vol.97, p.444-452
• Main Authors: Xiao, Jun, Xiao, Yang, Wang, Shijian, Huang, Zefu, Li, Jiayi, Gong, Cheng, Zhang, Guilai, Sun, Bing, Gao, Hong, Li, Huiqiao, Guo, Xin, Wang, Yong, Liu, Hao, Wang, Guoxiu
• Format: Article
• Language: English
• Subjects: Layered metal oxides; P2-type structure; Sodium-ion batteries; Surface engineering
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2024.06.007

A wet chemical method deposits an amorphous aluminum phosphate layer on P2-type Na0.55Ni0.1Co0.1Mn0.8O2, contributing to enhanced performance. This study reveals insights into phase stability and diffusion kinetics of coated electrode. [Display omitted] The widespread interest in layered P2-type Mn-based cathode materials for sodium-ion batteries (SIBs) stems from their cost-effectiveness and abundant resources. However, the inferior cycle stability and mediocre rate performance impede their further development in practical applications. Herein, we devised a wet chemical precipitation method to deposit an amorphous aluminum phosphate (AlPO4, denoted as AP) protective layer onto the surface of P2-type Na0.55Ni0.1Co0.1Mn0.8O2 (NCM@AP). The resulting NCM@5AP electrode, with a 5 wt% coating, exhibits extended cycle life (capacity retention of 78.4% after 200 cycles at 100 mA g−1) and superior rate performance (98 mA h g−1 at 500 mA g−1) compared to pristine NCM. Moreover, our investigation provides comprehensive insights into the phase stability and active Na+ ion kinetics in the NCM@5AP composite electrode, shedding light on the underlying mechanisms responsible for the enhanced performance observed in the coated electrode.