| 摘要 |
PROBLEM TO BE SOLVED: To provide a secondary battery capable of improving cycle characteristics thereof through reduction of a structural fracture caused by charge and discharge of a negative electrode as well as a reaction with an electrolyte.SOLUTION: A negative electrode active material layer 14B comprises at least one selected from the group consisting of a simple substance and alloys of Si capable of forming an alloy with Li. A positive electrode 12 and a negative electrode 14 are so arranged that the Li/Si molar ratio of the negative electrode 14 at the time of charging is 4.0 or less, or the potential of the negative electrode vs. Li is 0.04 V or more, by adjusting, for example, a ratio of a positive electrode active material and a negative electrode active material. The positive electrode and the negative electrode are also arranged so that the Li/Si molar ratio of the negative electrode 14 at the time of discharge is 0.4 or more, or the potential of the negative electrode vs. Li is 1.4 V or less. |
