| abstract |
A lithium ion secondary battery having high discharge characteristics and high cycle characteristics is provided. A lithium ion secondary battery of the present invention includes a positive electrode 10, a negative electrode 20, a separator 30 disposed between the positive electrode 10 and the negative electrode 20, and a non-aqueous electrolyte. A positive electrode current collector 11, a positive electrode active material layer 12 formed on the positive electrode current collector 11, and a conductive layer 13 formed on the positive electrode active material layer 12, the thickness of the conductive layer 13 being 1 μm or more and 7 μm or less. The positive electrode active material layer 12 includes a lithium-containing composite oxide and a conductive additive, and the content A of the conductive additive in the positive electrode active material layer 12 is 1% by weight or more based on the total weight of the positive electrode active material layer 12. The conductive layer 13 contains a conductive additive, and the conductive additive content B of the conductive layer 13 is 20% by weight to 80% by weight with respect to the total weight of the conductive layer. [Selection] Figure 1 |