Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7736892 | Journal of Power Sources | 2014 | 8 Pages |
Abstract
Cycle performance at 60 °C for a Li Al0.10Ni0.76Co0.14O2 (NCA) cathode/graphite cell was greatly improved when a DOD range in charge-discharge cycling (ÎDOD) was restricted. The deterioration mechanism was analyzed by X-ray photoelectron spectroscopy (XPS), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and scanning transmission electron microscopy-electron energy-loss spectroscopy (STEM-EELS). Only after the cycle test in the ÎDOD of 0-100%, many micro-cracks were generated in the inter-surface between the primary particles which aggregated to form the secondary particles, and a NiO-like resistance layer with Fm3m rock salt structure was formed on each primary particle which was contact with other primary particles and electrolyte. It can be concluded that the lack of contact between the primary particles with the micro-crack generation and the formation of the new resistance layer are responsible for the capacity fading and the rise in impedance during charge-discharge cycle in the wide ÎDOD.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Shoichiro Watanabe, Masahiro Kinoshita, Takashi Hosokawa, Kenichi Morigaki, Kensuke Nakura,