| 摘要 |
Provided is a lithium-ion secondary cell in which a lithium-nickel composite oxide having a high Ni content is included in a positive electrode, wherein the lithium-ion secondary cell has excellent cycle characteristics at high temperatures. This lithium-ion secondary cell is provided with a positive electrode, a negative electrode, and an electrolyte, and is characterized in that the positive electrode contains the lithium-nickel composite oxide represented by general formula LiNixCoyMnzO2 (x, y, and z are within the ranges, respectively, 0.75 ≤ x ≤ 0.85, 0.05 ≤ y ≤ 0.15, and 0.10 ≤ z ≤ 0.20.) |
