TY  - JOUR
AU  - Du, Leilei
AU  - Hou, Xu
AU  - Berghus, Debbie
AU  - Frankenstein, Lars
AU  - Schmuch, Richard
AU  - Wang, Jun
AU  - Paillard, Elie
AU  - Winter, Martin
AU  - Placke, Tobias
AU  - Li, Jie
TI  - Failure mechanism of LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathodes in aqueous/non-aqueous hybrid electrolyte
JO  - Journal of materials chemistry / A
VL  - 11
IS  - 7
SN  - 2050-7488
CY  - London ˜[u.a.]œ
PB  - RSC
M1  - FZJ-2024-02542
SP  - 3663 - 3672
PY  - 2023
N1  - Unterstützt durch DFG Projekt Li 2916/2-1 und das MWIDE Projekt "GrEEn" (313-W044A)
AB  - 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000922078300001
DO  - DOI:10.1039/D2TA08650F
UR  - https://juser.fz-juelich.de/record/1024891
ER  -