skip to main content

DOE PAGESDOE PAGES

Title: Electrolyte-induced surface transformation and transition-metal dissolution of fully delithiated LiNi 0.8Co 0.15Al 0.05O 2

Here, enabling practical utilization of layered R$$\bar{3}$$ m positive electrodes near full delithiation requires an enhanced understanding of the complex electrode–electrolyte interactions that often induce failure. Using Li[Ni 0.8Co 0.15Al 0.05]O 2 (NCA) as a model layered compound, the chemical and structural stability in a strenuous thermal and electrochemical environment was explored. Operando microcalorimetry and electrochemical impedance spectroscopy identified a fingerprint for a structural decomposition and transition-metal dissolution reaction that occurs on the positive electrode at full delithiation. Surface-sensitive characterization techniques, including X-ray absorption spectroscopy and high-resolution transmission electron microscopy, measured a structural and morphological transformation of the surface and subsurface regions of NCA. Despite the bulk structural integrity being maintained, NCA surface degradation at a high state of charge induces excessive transition-metal dissolution and significant positive electrode impedance development, resulting in a rapid decrease in electrochemical performance. Additionally, the impact of electrolyte salt, positive electrode surface area, and surface Li 2CO 3 content on the magnitude and character of the dissolution reaction was studied.
Authors:
ORCiD logo [1] ;  [2] ;  [3] ;  [2] ;  [1] ;  [1] ;  [1] ;  [4] ;  [3] ; ORCiD logo [2] ; ORCiD logo [1]
  1. Rutgers Univ., North Brunswick, NJ (United States)
  2. Binghamton Univ., Binghamton, NY (United States)
  3. Rutgers Univ., Piscataway, NJ (United States)
  4. Univ. of California, Berkeley, CA (United States)
Publication Date:
Grant/Contract Number:
SC0012583
Type:
Accepted Manuscript
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 33; Journal Issue: 37; Journal ID: ISSN 0743-7463
Publisher:
American Chemical Society
Research Org:
Rutgers Univ., New Brunswick, NJ (United States); Energy Frontier Research Centers (EFRC) (United States). Northeastern Center for Chemical Energy Storage (NECCES)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
25 ENERGY STORAGE; 36 MATERIALS SCIENCE
OSTI Identifier:
1364759