Formation of Surface Impurities on Lithium–Nickel–Manganese–Cobalt Oxides in the Presence of CO2 and H2O

• DOI: 10.1021/jacs.1c03812
• Publication Date: 2021-07-02T18:37:05Z
• Authors: Zongtang Fang; Matthew P. Confer; Yixiao Wang; Qiang Wang; M. Ross Kunz; Eric J. Dufek; Boryann Liaw; Tonya M. Klein; David A. Dixon; Rebecca Fushimi
• Keywords: Reactivity; Non-blocking I/O; Exothermic reaction

Surface impurities involving parasitic reactions and gas evolution contribute to the degradation of high Ni content LiNixMnyCozO2 (NMC) cathode materials. The transient kinetic technique temporal analysis products (TAP), density functional theory, infrared spectroscopy have been used study formation surface on varying nickel NMC materials (NMC811, NMC622, NMC532, NMC433, NMC111) in presence CO2 H2O. reactivity a clean as characterized by conversion rate TAP reactor follows order: NMC811 > NMC622 NMC532 NMC433 NMC111. capacity uptake different Moisture pretreatment slows down direct adsorption process creates additional active sites for adsorption. Electronic structure calculations predict that (012) is more reactive than (1014) H2O leading carbonate exothermic with ion pairs. average binding energies follow order. Water hydroxylates OH groups favor bicarbonate formation. due hydrogen bonding. composition formed ambient air exposure dependent water concentration percentage crystal planes. Different reactivities suggest battery performance can be mitigated precise control dominant surfaces