TY  - JOUR
AU  - Kleiner, Karin
AU  - Dixon, Ditty
AU  - Jakes, Peter
AU  - Melke, Julia
AU  - Yavuz, Murat
AU  - Roth, Christina
AU  - Nikolowski, Kristian
AU  - Liebau, Verena
AU  - Ehrenberg, Helmut
TI  - Fatigue of LiNi$_{0.8}$  Co$_{0.15}$Al$_{0.05}$O$_{2}$ in commercial Li ion batteries
JO  - Journal of power sources
VL  - 273
SN  - 0378-7753
CY  - New York, NY [u.a.]
PB  - Elsevier
M1  - FZJ-2014-06533
SP  - 70 - 82
PY  - 2015
AB  - The degradation of LiNi0.8Co0.15Al0.05O2 (LNCAO), a cathode material in lithium-ion-batteries, was studied using in situ powder diffraction and in situ Ni K edge X-ray absorption spectroscopy (XAS). The fatigued material was taken from a 7 Ah battery which was cycled for 34 weeks under defined durability conditions. Meanwhile, a cell was stored, as reference, under controlled conditions without electrochemical treatment. The fatigued LNCAO used in this study showed a capacity loss of 26% ± 9% compared to the non-cycled material. During charge and discharge the local and the overall structure of LNCAO was investigated by X-ray near edge structure (XANES) analysis, the extended X-ray absorption fine structure (EXAFS) analysis and by using Rietveld refinement of in situ powder diffraction patterns. Both powder diffraction and XAS revealed additional, rhombohedral phases which do not change with electrochemical cycling. Moreover, a phase with the lattice parameters of fully lithiated LNCAO was still present in the fatigued material at high potentials, while it was absent in the non-fatigued reference material. The coexistence of these phases is described by domains within the LNCAO particles, in correlation with the observed fatigue.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000345725700008
DO  - DOI:10.1016/j.jpowsour.2014.08.133
UR  - https://juser.fz-juelich.de/record/173120
ER  -