Affiliation:
1. Department of Materials Science Fudan University Shanghai 200433 China
2. State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China
3. School of Materials Science and Engineering Anhui University Hefei 230601 China
Abstract
AbstractSingle‐crystal lithium–nickel–manganese–cobalt‐oxide (SC‐NMC) is attracting increasing attention due to its excellent structural stability. However, its practical production faces challenges associated with complex precursor preparation processes and severe lithium–nickel cation mixing at high temperatures, which restricts its widespread application. Here, a molten‐salt‐assisted method is proposed using low‐melting‐point carbonates. This method obviates the necessity for precursor processes and simplified the synthetic procedure for SC‐NMC down to a single isothermal sintering step. Multiple characterizations indicate that the acquired SC‐LiNi0.6Mn0.2Co0.2O2 (SC‐622) exhibits favorable structural capability against intra‐granular fracture and suppressive Li+/Ni2+ cation mixing. Consequently, the SC‐622 exhibits superior electrochemical performance with a high initial specific capacity (174 mAh g−1 at 0.1 C, 3.0–4.3 V) and excellent capacity retention (87.5% after 300 cycles at 1C). Moreover, this molten‐salt‐assisted method exhibits its effectiveness in directly regenerating SC‐622 from spent NMC materials. The recovered material delivered a capacity of 125.4 mAh g−1 and retained 99.4% of the initial capacity after 250 cycles at 1 C. This work highlights the importance of understanding the process‐structure‐property relationships and can broadly guide the synthesis of other SC Ni‐rich cathode materials.