Details

Autor(en) / Beteiligte

• Li, Jianyu
• Manthiram, Arumugam

Titel

A Comprehensive Analysis of the Interphasial and Structural Evolution over Long‐Term Cycling of Ultrahigh‐Nickel Cathodes in Lithium‐Ion Batteries

Ist Teil von

• Advanced energy materials, 2019-12, Vol.9 (45), p.n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2019

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Ultrahigh‐Ni layered oxides hold great promise as high‐energy‐density cathodes at an affordable cost for lithium‐ion batteries, yet their practical application is greatly hampered by the poor cyclability. Herein, by employing LiNi0.94Co0.06O2 as a model cathode in a full‐cell configuration, the interphasial and structural evolution processes of ultrahigh‐Ni layered oxides are systematically investigated over the course of their service life (1500 cycles). By applying advanced analytic techniques (e.g., Li‐isotope labeling, region‐of‐interest method), the dynamic chemical evolution on the cathode surface is revealed with spatial resolution, and the correlation between lattice distortion and cathode surface reactivity is established. Benefiting from in situ X‐ray diffraction (XRD) analysis, the ultrahigh‐Ni layered oxide is demonstrated to undergo dual‐phase reaction mechanisms with huge lattice variation, which leads to a decrease in crystallinity and secondary particle pulverization. Furthermore, the critical impact of cathode surface reaction on the graphite anode–electrolyte interphase (AEI) is revealed at nanometer scale, and a universal chemical/physical evolution process of the AEI is illustrated, for the first time. Finally, the practical viability of ultrahigh‐Ni layered oxides is demonstrated through Al‐doping strategy. This work presents a comprehensive understanding of the structural and interphasial degradation of ultrahigh‐Ni layered oxide cathodes for developing high‐energy‐density lithium‐ion batteries. A systematic investigation on the interphasial and structural evolution processes of a model ultrahigh‐Ni layered oxide (LiNi0.94Co0.06O2) over the course of full‐cell life (1500 cycles) is presented in this work. The correlation between the structural and interphasial evolution is established along with the implication of cathode–electrolyte interphase on the graphite–electrolyte interphase.