Microvoltammetry of lithium nickel oxide single particle: deterioration of the redox behavior by water molecules

The microelectrode technique was applied to investigate the electrochemical behavior of LiNiO2 which seriously influenced by water molecules. Cyclic voltammograms of humidified LiNiO2 particles were compared to that of as-synthesized. As a result, a significant peak-potential shift was observed, which denotes that the reaction product caused by H2O generates an electrochemical inactive material on the particle which prevents the Li+ insertion/extraction. The reaction product was considered to be NiO, and deterioration property has also been discussed.