A highly stabilized nickel-rich cathode material by nanoscale epitaxy control for high-energy lithium-ion batteries

• Published in: Energy & environmental science 2018-01, Vol.11 (6), p.1449-1459
• Main Authors: Kim, Junhyeok, Ma, Hyunsoo, Cha, Hyungyeon, Lee, Hyomyung, Sung, Jaekyung, Seo, Minho, Oh, Pilgun, Park, Minjoon, Cho, Jaephil
• Format: Article
• Language: English
• Subjects: Anodes; Batteries; Battery cycles; Cathodes; Cycles; Electrode materials; Electrolytic cells; Lithium; Lithium-ion batteries; Metal particles; Nickel; Rechargeable batteries; Solid electrolytes; Structural integrity; Structural stability; Thermal stability
• ISSN: 1754-5692; 1754-5706
• DOI: 10.1039/c8ee00155c

Advanced surface engineering of nickel-rich cathode materials greatly enhances their structural/thermal stability. However, their application into lithium-ion full-cells still faces challenges, such as the unstable solid electrolyte interphase (SEI) layer on the anode. Herein, we reveal that the degradation of battery cycle life is caused by the release of divalent nickel ions from the LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode and the formation of nickel metal particles on the graphite anode surface, deteriorating the anode SEI layer and its structural integrity. On the basis of this finding, we demonstrate a stable lithium-ion battery by modifying the cathode surface by creating a nanostructured stabilizer with an epitaxial structure that enhances the morphological robustness. During cycling, the nickel defects in the cathode are significantly suppressed, preventing nickel ion crossover. In particular, the anode SEI layer maintains a uniform and dense structure, leading to outstanding cycling stability in the full-cell with a capacity retention of ∼86% after 400 cycles at 25 °C. An epitaxy layer on the LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode significantly suppressed the nickel-ion crossover, which enhanced the structural/electrochemical stability at high temperature.