Active material, nonaqueous electrolyte battery, battery pack and battery module

A nonaqueous electrolyte battery, comprising:

• a negative electrode comprising a negative electrode active material;
• a positive electrode;
• and
• a nonaqueous electrolyte.
• wherein the negative electrode active material comprises:
• a composite oxide having an orthorhombic crystal structure and represented by a general formula of Li2+wNa2−xM1yTi6−zM2zO14+δ, wherein
• the M1 is at least one selected from the group consisting of Cs and K,
• the M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, W, Fe, Co, Mn, and Al, and
• w is within a range of 0≤w≤4, x is within a range of 0<x<2, y is within a range of 0≤y<2, z is within a range of 0<z≤6, and δ is within a range of −0.5≤δ≤0.5
• wherein a difference in a potential from 20% state-of-charge to 80% state-of-charge of the negative electrode is within a range of 40 mV to 200 mV, and the negative electrode exhibits a continuous potential change within a potential range of 1.0 V to 1.45 V (versus Li/Li+).