skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The Phase Evolution and Degradation Modes of $$ R\overline{3}\ m$$ Li xNi 1-y-zCo yAl zO 2 Electrodes Cycled Near Complete Delithiation

Abstract

We report that the practical utilization of energy densities near the theoretical limit for $$ R\overline{3}\ m$$ layered oxide positive electrode materials is dependent on the stability of the electrochemical performance of these materials at or near full delithiation. In order to develop new chemistries and novel approaches towards the improvement of the electrochemical performance of these materials at such high states of charge, a robust understanding of the failure mechanisms limiting current materials is necessary. Thorough analysis of Li xCo 1-yAl yO 2 and Li xNi 1-yAl yO 2 as well as Li xNi 0.8Co 0.2O 2 and Li xNi 0.8Co 0.15Al 0.05O 2 (1 ≥ x ≥ 0 and 0.2 ≥ y ≥ 0) enabled the identification of key relationships between the transition metal chemistry of the electrode, its structural stability, and cycling characteristics at or near complete delithiation (4.75 V). Extensive characterization of these materials was achieved by a multitude of physical and electrochemical techniques to investigate the relative importance of surface vs. bulk phenomena. Here, the resulting insights derived from these analyses highlight the importance of the intrinsic structural and mechanical stability of the electrode when highly delithiated and establish guidelines for identifying positive electrode materials with improved high state of charge performance. Lastly, particularly important is the contrasting electrochemical impact of Al substitution into LiCoO 2- and LiNiO 2-based materials, which is shown to likely arise from the enhanced propensity for Al ions to migrate to the tetrahedral site in Co-rich compounds at high states of delithiation.

Authors:
Publication Date:
Research Org.:
Energy Frontier Research Centers (EFRC) (United States). Northeastern Center for Chemical Energy Storage (NECCES); Rutgers Univ., New Brunswick, NJ (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1477223
Grant/Contract Number:  
SC0012583
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Chemistry of Materials
Additional Journal Information:
Journal Volume: 0; Journal Issue: 0; Related Information: Supplemental information for The Phase Evolution and Degradation Modes of R3 ̅m LixNi1-y-zCoyAlzO2 Electrodes Cycled Near Complete Delithiation; Journal ID: ISSN 0897-4756
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
25 ENERGY STORAGE; 36 MATERIALS SCIENCE; Positive electrode materials; full delithiation; microcalorimetry; in-situ XRD

Citation Formats

None, None. The Phase Evolution and Degradation Modes of $ R\overline{3}\ m$ LixNi1-y-zCoyAlzO2 Electrodes Cycled Near Complete Delithiation. United States: N. p., 2018. Web. doi:10.1021/acs.chemmater.8b02720.
None, None. The Phase Evolution and Degradation Modes of $ R\overline{3}\ m$ LixNi1-y-zCoyAlzO2 Electrodes Cycled Near Complete Delithiation. United States. doi:10.1021/acs.chemmater.8b02720.
None, None. Tue . "The Phase Evolution and Degradation Modes of $ R\overline{3}\ m$ LixNi1-y-zCoyAlzO2 Electrodes Cycled Near Complete Delithiation". United States. doi:10.1021/acs.chemmater.8b02720. https://www.osti.gov/servlets/purl/1477223.
@article{osti_1477223,
title = {The Phase Evolution and Degradation Modes of $ R\overline{3}\ m$ LixNi1-y-zCoyAlzO2 Electrodes Cycled Near Complete Delithiation},
author = {None, None},
abstractNote = {We report that the practical utilization of energy densities near the theoretical limit for $ R\overline{3}\ m$ layered oxide positive electrode materials is dependent on the stability of the electrochemical performance of these materials at or near full delithiation. In order to develop new chemistries and novel approaches towards the improvement of the electrochemical performance of these materials at such high states of charge, a robust understanding of the failure mechanisms limiting current materials is necessary. Thorough analysis of LixCo1-yAlyO2 and LixNi1-yAlyO2 as well as LixNi0.8Co0.2O2 and LixNi0.8Co0.15Al0.05O2 (1 ≥ x ≥ 0 and 0.2 ≥ y ≥ 0) enabled the identification of key relationships between the transition metal chemistry of the electrode, its structural stability, and cycling characteristics at or near complete delithiation (4.75 V). Extensive characterization of these materials was achieved by a multitude of physical and electrochemical techniques to investigate the relative importance of surface vs. bulk phenomena. Here, the resulting insights derived from these analyses highlight the importance of the intrinsic structural and mechanical stability of the electrode when highly delithiated and establish guidelines for identifying positive electrode materials with improved high state of charge performance. Lastly, particularly important is the contrasting electrochemical impact of Al substitution into LiCoO2- and LiNiO2-based materials, which is shown to likely arise from the enhanced propensity for Al ions to migrate to the tetrahedral site in Co-rich compounds at high states of delithiation.},
doi = {10.1021/acs.chemmater.8b02720},
journal = {Chemistry of Materials},
issn = {0897-4756},
number = 0,
volume = 0,
place = {United States},
year = {2018},
month = {10}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share: