LITHIUM ION SECONDARY BATTERY

Provided is a lithium ion secondary battery having an excellent endurance and high output characteristics. A lithium ion secondary battery of the present invention is provided with a positive electrode, a negative electrode, a separator, and a nonaqueous electrolyte containing lithium ions. The negative electrode includes a negative electrode power collector and a negative electrode active material layer that includes a negative electrode active material and is disposed on one face or both faces of the negative electrode power collector. The positive electrode includes a positive electrode power collector and a positive electrode active material layer that includes a positive electrode active material and is disposed on one face or both faces of the positive electrode power collector. The positive electrode active material includes a transition metal oxide capable of occluding and releasing lithium ions. The positive electrode active material layer contains a specific lithium compound in the proportion of 3.8×10 -9 mol/g-3.0×10 -2 mol/g per unit mass of the positive electrode active material layer.