Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Failure mechanism of LiNi0.6Co0.2Mn0.2O2 cathodes in aqueous/non-aqueous hybrid electrolyte

Du, Leilei ; Hou, Xu LU orcid ; Berghus, Debbie ; Frankenstein, Lars ; Schmuch, Richard ; Wang, Jun ; Paillard, Elie ; Winter, Martin ; Placke, Tobias and Li, Jie (2023) In Journal of Materials Chemistry A 11(7). p.3663-3672
Abstract

The urgent need for improving the energy density of aqueous lithium ion batteries (ALIBs) can be addressed by the implementation of advanced electrode materials and electrolytes. The utilization of layered oxide cathodes, particularly Li[NixCoyMnz]O2 (NCM) materials, is an effective strategy, as they can offer high specific capacities in an appropriate voltage range. However, due to the strong effect of humidity on the degradation of Ni-rich layered oxide cathodes, using these materials together with highly concentrated aqueous electrolytes is critical. In this work, the underlying mechanisms responsible for the degradation of Li[Ni0.6Co0.2Mn0.2]O2... (More)

The urgent need for improving the energy density of aqueous lithium ion batteries (ALIBs) can be addressed by the implementation of advanced electrode materials and electrolytes. The utilization of layered oxide cathodes, particularly Li[NixCoyMnz]O2 (NCM) materials, is an effective strategy, as they can offer high specific capacities in an appropriate voltage range. However, due to the strong effect of humidity on the degradation of Ni-rich layered oxide cathodes, using these materials together with highly concentrated aqueous electrolytes is critical. In this work, the underlying mechanisms responsible for the degradation of Li[Ni0.6Co0.2Mn0.2]O2 (NCM622)‖TiO2@LiTi2(PO4)3 (P/N = 1.2 : 1) full-cells are systematically explored by comprehensive studies, involving the evolution of the lattice structure of NCM622 and electrochemical impedance dependent on the operating voltage range (0.7-2.8 V or 0.7-2.9 V). It is found that in aqueous/non-aqueous hybrid electrolyte, in addition to the discharge process, proton intercalation into NCM622 also takes place during the charging process, which is dramatically severe at higher upper cut-off voltage (2.9 V), leading to a rapid degradation of the cathode material. The intercalated protons not only aggravate the electrochemical impedance by blocking Li+ diffusion, but also activate the higher potential redox pairs. This experimental study offers an in-depth understanding about the failure mechanism of NCM622 cathode materials in aqueous electrolytes.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; ; ; ; and
publishing date
type
Contribution to journal
publication status
published
in
Journal of Materials Chemistry A
volume
11
issue
7
pages
10 pages
publisher
Royal Society of Chemistry
external identifiers
  • scopus:85147570190
ISSN
2050-7488
DOI
10.1039/d2ta08650f
language
English
LU publication?
no
additional info
Publisher Copyright: © 2023 The Royal Society of Chemistry.
id
6523d850-db66-4566-9600-06f56689d6fe
date added to LUP
2025-12-05 22:30:28
date last changed
2025-12-11 12:34:50
@article{6523d850-db66-4566-9600-06f56689d6fe,
  abstract     = {{<p>The urgent need for improving the energy density of aqueous lithium ion batteries (ALIBs) can be addressed by the implementation of advanced electrode materials and electrolytes. The utilization of layered oxide cathodes, particularly Li[Ni<sub>x</sub>Co<sub>y</sub>Mn<sub>z</sub>]O<sub>2</sub> (NCM) materials, is an effective strategy, as they can offer high specific capacities in an appropriate voltage range. However, due to the strong effect of humidity on the degradation of Ni-rich layered oxide cathodes, using these materials together with highly concentrated aqueous electrolytes is critical. In this work, the underlying mechanisms responsible for the degradation of Li[Ni<sub>0.6</sub>Co<sub>0.2</sub>Mn<sub>0.2</sub>]O<sub>2</sub> (NCM622)‖TiO<sub>2</sub>@LiTi<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> (P/N = 1.2 : 1) full-cells are systematically explored by comprehensive studies, involving the evolution of the lattice structure of NCM622 and electrochemical impedance dependent on the operating voltage range (0.7-2.8 V or 0.7-2.9 V). It is found that in aqueous/non-aqueous hybrid electrolyte, in addition to the discharge process, proton intercalation into NCM622 also takes place during the charging process, which is dramatically severe at higher upper cut-off voltage (2.9 V), leading to a rapid degradation of the cathode material. The intercalated protons not only aggravate the electrochemical impedance by blocking Li<sup>+</sup> diffusion, but also activate the higher potential redox pairs. This experimental study offers an in-depth understanding about the failure mechanism of NCM622 cathode materials in aqueous electrolytes.</p>}},
  author       = {{Du, Leilei and Hou, Xu and Berghus, Debbie and Frankenstein, Lars and Schmuch, Richard and Wang, Jun and Paillard, Elie and Winter, Martin and Placke, Tobias and Li, Jie}},
  issn         = {{2050-7488}},
  language     = {{eng}},
  month        = {{01}},
  number       = {{7}},
  pages        = {{3663--3672}},
  publisher    = {{Royal Society of Chemistry}},
  series       = {{Journal of Materials Chemistry A}},
  title        = {{Failure mechanism of LiNi<sub>0.6</sub>Co<sub>0.2</sub>Mn<sub>0.2</sub>O<sub>2</sub> cathodes in aqueous/non-aqueous hybrid electrolyte}},
  url          = {{http://dx.doi.org/10.1039/d2ta08650f}},
  doi          = {{10.1039/d2ta08650f}},
  volume       = {{11}},
  year         = {{2023}},
}