Lithium secondary battery

A lithium secondary battery, comprising:

• a wound electrode group;
• and a non-aqueous electrolyte,
• the wound electrode group including:
• a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, a positive electrode lead electrically connected to the positive electrode, and a negative electrode lead electrically connected to the negative electrode, the positive electrode and the negative electrode being wound with the separator between the positive electrode and the negative electrode, wherein
• the positive electrode includes a positive electrode mixture layer containing a positive electrode active material, and a positive electrode current collector;
• the positive electrode active material includes a composite oxide containing lithium and a transition metal;
• a molar ratio:
• MLi/MTM of a total lithium amount per unit area MLi in the positive electrode and the negative electrode to a transition metal amount per unit area MTM in the positive electrode is 1.1 or less;
• the negative electrode includes a negative electrode current collector;
• the negative electrode current collector is larger in area than the positive electrode mixture layer;
• in the wound electrode group in an unwound state,
• a center line dividing the positive electrode mixture layer along a winding direction into two halves and a center line dividing the negative electrode current collector along the winding direction into two halves are not on a same straight line;
• and
• the negative electrode lead is connected at its one end to a non-facing region not facing the positive electrode mixture layer of the negative electrode current collector.