To provide a secondary battery capable of improving its cycle characteristics through reduction of a structural fracture caused by charge and discharge of an anode as well as reaction with electrolyte.

An anode active material layer 14B includes at least one kind of group consisting of a simple substance and alloys of Si capable of forming an alloy with Li. A cathode 12 and an anode 14 are so arranged that an Li/Si molar ratio of the anode at the time of charging is 4.0 or less, or a potential of the anode vs. Li is 0.04 or more, by adjusting, for example, a ratio of the cathode active material and the anode active material. The cathode and the anode are also arranged so that an Li/Si molar ratio of the anode at the time of discharge is 0.4 or more, or a potential of the anode vs. Li is 1.4V or less.

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