| 摘要 |
A lithium ion secondary battery according to an embodiment has: an electrode assembly formed by rolling up a positive electrode, a separator, and a negative electrode; an organic electrolyte solution; a positive electrode lead connected to the positive electrode; a negative electrode lead connected to the negative electrode; and an overcharge prevention mechanism, which are incorporated in a battery can sealed with a cap body, and includes: a positive electrode terminal fixed to the cap body, and connected to the positive electrode lead; and a negative electrode terminal fixed to the cap body and connected to the negative electrode lead. Further, the overcharge prevention mechanism includes: a temperature-sensitive deformation member configured to detect the internal temperature of the electrode assembly to undergo shape change; a switch member configured to be driven by the shape change of the temperature-sensitive deformation member; a fuse member connected in series between the positive electrode terminal and the positive electrode or the negative electrode terminal and the negative electrode; and a short circuit configured to connect the electrode assembly, the fuse member, and the switch member of the lithium ion secondary battery. |
