| 摘要 |
PROBLEM TO BE SOLVED: To provide a power storage device which can surely cut off a current when overcharged, without heightening electrical resistance during normal operation, and a secondary battery incorporating that structure.SOLUTION: The power storage device disclosed in the present specification comprises: a current cutoff mechanism which can be actuated when the internal pressure of a case becomes or rises above a first pressure to cut off an electrical conduction path between an external terminal and an electrode sheet on at least either side of a cathode and an anode; an accommodation chamber provided in the case; a liquid or solid first reactant disposed in the accommodation chamber; a liquid or solid second reactant, disposed in the case and outside the accommodation chamber, which generates gas when it is mixed with the first reactant to react thereon; and a valve, disposed in the accommodation chamber, which is located at a position at which, when opened, the first reactant moves toward the second reactant. The valve is opened when the internal pressure of the case is equal to or higher than a second pressure which is lower than the first pressure. |
