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

According to one embodiment, an active material is provided. The active material includes a lithium niobium composite oxide represented by a general formula LiFeM1NbM2O(1) and having an orthorhombic crystal structure. In the general formula (1), 0≤x≤23, 0≤y≤1 and 0