Nonaqueous electrolyte secondary battery

A non-aqueous electrolyte secondary battery, comprising:

• a positive electrode including a positive electrode active material;
• a negative electrode;
• and
• a non-aqueous electrolyte, wherein
• the positive electrode includes:
• a lithium-transition metal composite oxide (A) having a median diameter on a volumetric basis (D50) of 0.6 μm to 3 μm and being a secondary particle formed by aggregation of primary particles having an average particle diameter of 0.5 μm or larger or being composed of substantially single particles;
• and a lithium-transition metal composite oxide (B) having a median diameter on a volumetric basis (D50) of 6 μm to 25 μm and being a secondary particle formed by aggregation of primary particles having an average particle diameter of 0.3 μm or smaller, as the positive electrode active material;
• the lithium-transition metal composite oxide (A) contains 65 mol % or more of Ni based on a total number of moles of metal elements excluding Li, and Ti is not present on a particle surface of the lithium-transition metal composite oxide (A);
• the lithium-transition metal composite oxide (B) contains 70 mol % or more of Ni based on a total number of moles of metal elements excluding Li, and Ti is present on a particle surface of the oxide;
• and
• in the lithium-transition metal composite oxide (B), when particles having a particle diameter larger than a 70% particle diameter (D70) on a volumetric basis are defined as first particles, and particles having a particle diameter smaller than a 30% particle diameter (D30) on a volumetric basis are defined as second particles,
• a mole fraction of Ti on surfaces of the second particles based on a total number of moles of metal elements excluding Li on surfaces of the second particles (B2) is larger than a mole fraction of Ti on surfaces of the first particles based on a total number of moles of metal elements excluding Li on surfaces of the first particles (B1), and
• a ratio of the mole fraction of Ti on surfaces of the second particles (B2) to the mole fraction of Ti on surfaces of the first particles (B1) is 1.10 or more and 1.50 or less.