ELECTRODE MATERIAL, ELECTRODE, SECONDARY BATTERY, BATTERY PACK, AND VEHICLE

An electrode material may include an active material particle containing: a niobium-titanium composite oxide having an average composition in which a molar ratio of niobium to titanium (M/M) is greater than 2; and at least one element A selected from the group consisting of potassium, iron and phosphorus. The active material particle may contain the element A at a concentration in the range of 100 ppm to 2000 ppm.