Influence of state-of-charge in commercial LiNi0.33Mn0.33Co0.33O2/LiMn2O4-graphite cells analyzed by synchrotron-based photoelectron spectroscopy
Journal article, 2018

Degradation mechanisms in 26 Ah commercial Li-ion battery cells comprising graphite as the negative electrode and mixed metal oxide of LiMn 2 O 4 (LMO) and LiNi 1/3 Mn 1/3 Co 1/3 O 2 (NMC) as the positive electrode are here investigated utilising extensive cycling at two different state-of-charge (SOC) ranges, 10–20% and 60–70%, as well as post-mortem analysis. To better analyze these mechanisms electrochemically, the cells were after long-term cycling reassembled into laboratory scale “half-cells” using lithium metal as the negative electrode, and thereafter cycled at different rates corresponding to 0.025 mA/cm 2 and 0.754 mA/cm 2 . The electrodes were also analyzed by synchrotron-based hard x-ray photoelectron spectroscopy (HAXPES) using two different excitation energies to determine the chemical composition of the interfacial layers formed at different depth on the respective electrodes. It was found from the extensive cycling that the cycle life was shorter for the cell cycled in the higher SOC range, 60–70%, which is correlated to findings of an increased cell resistance and thickness of the SEI layer in the graphite electrode as well as manganese dissolution from the positive electrode.

Battery ageing

Commercial cells

Photoelectron spectroscopy

Li-ion battery

Author

Erik Björklund

Uppsala University

Evelina Wikner

Chalmers, Electrical Engineering, Electric Power Engineering

Reza Younesi

Uppsala University

D. Brandell

Uppsala University

K. Edstrom

Uppsala University

Journal of Energy Storage

2352-152X (eISSN)

Vol. 15 172-180

Ageing mechanisms and how to prolong the battery life in vehicle and energy storage applications

Swedish Energy Agency (37725-1), 2014-04-01 -- 2017-06-30.

Ageing mechanisms & how to prolong battery life in vehicle and energy storage applications’

Volvo Cars (4150395483), 2016-11-09 -- 2016-11-30.

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Chemical Engineering

DOI

10.1016/j.est.2017.11.010

More information

Latest update

2/16/2023