Facile self-templated synthesis of P2-type NaCoO microsheets as a long-term cathode for high-energy sodium-ion batteries

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 7; no. 23; pp. 13922 - 13927
• Main Authors: Peng, Bo, Sun, Zhihao, Jiao, Shuhong, Li, Jie, Wang, Gongrui, Li, Yapeng, Jin, Xu, Wang, Xiaoqi, Li, Jianming, Zhang, Genqiang
• Format: Journal Article
• Language: English
• Published: 11.06.2019
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c9ta02966d

Sodium-ion batteries are one of the most promising candidates for large-scale energy storage systems due to the low cost of sodium source and their similar working principle to lithium-ion batteries. However, the demerit of poor cycling stability of the cathode severely restricts the advancement of sodium-ion battery-based practical applications. Herein, we report a facile self-template-directed two-step strategy to fabricate microsheet-like P2-type Na 0.7 CoO 2 with greatly enhanced high rate cycling stability when applied as a cathode for SIBs. Specifically, it can deliver a high specific capacity of 137.7 mA h g −1 at a current density of 10 mA g −1 and exhibits impressive long-term cycling stability, with a capacity retention of 94% after 1000 cycles at a high rate of 500 mA g −1 ; this performance is outstanding compared with previous results for layered metal oxide cathodes. More importantly, a sodium-ion full cell based on the P2-type Na 0.7 CoO 2 microsheet cathode was further built to demonstrate its possibilities for practical applications, where inspiring results can be observed, with promising cycling stability and high power/energy densities. This study demonstrates the great potential of layered metal oxide cathodes in practical applications, which can help advance grid-level energy storage systems. Sodium-ion batteries are one of the most promising candidates for large-scale energy storage systems due to the low cost of sodium source and their similar working principle to lithium-ion batteries.