| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery having a positive electrode that is set to ensure excellent cycle characteristics.SOLUTION: A lithium ion secondary battery 100 has a positive electrode 30 in which the porosity P of a positive electrode active material is set equal to a target porosity Por more, where the target porosity Pis the porosity P of a positive electrode active material when the cycle characteristics of the lithium ion secondary battery 100, having the positive electrode 30 formed using a positive electrode active material of smallest crystalline size out of the positive electrode active materials that can be used as a positive electrode material, become desired cycle characteristics C. |
