TITANIUM-NIOBIUM OXIDES, AND ELECTRODES AND LITHIUM-ION SECONDARY CELLS INCLUDING TITANIUM-NIOBIUM OXIDES

A titanium-niobium oxide achieves suppressed adulteration with TiO and TiNbO and suppressed growth of crystal grains, and an electrode and a lithium-ion secondary cell include such a titanium-niobium oxide. The titanium-niobium oxide contains less than 0.30 at% of an alkali metal element and at least one element selected from the group consisting of Al, Y, La, Ce, Pr, and Sm. A ratio of a total atomic weight of Al, Y, La, Ce, Pr, and Sm to a total atomic weight of Ti and Nb is equal to or more than 0.001.