| 摘要 |
PROBLEM TO BE SOLVED: To provide a lithium ion secondary battery which allows even a voltage detector with low accuracy to make a diagnosis about a state of charge.SOLUTION: In a lithium ion secondary battery, at least one of a positive electrode and a negative electrode includes 3 kinds of active materials. The positive electrode active materials included in the positive electrode are selected from a first positive electrode active material of which the average potential is 4 V or higher, a second positive electrode active material of which the average potential is 3.5 to lower than 4 V, and a third positive electrode active material of which the average potential is lower than 3.5 V. The negative electrode active materials included in the negative electrode are selected from a first negative electrode active material of which the average potential is lower than 0.3 V, a second negative electrode active material of which the average potential is 0.3 to lower than 0.6 V, and a third negative electrode active material of which the average potential is 0.6 V or higher.SELECTED DRAWING: Figure 6 |
