| 摘要 |
PROBLEM TO BE SOLVED: To obtain a secondary battery that improves the insulation properties between an electrode group and a battery can for protecting the electrode group from an external force without deteriorating the battery capacity.SOLUTION: A secondary battery 1 of this invention includes: a battery can 4 housing a wound electrode group 40; and an insulator 5 disposed between the wound electrode group 40 and the battery can 4. In the wound electrode group 40, collector plates 21, 31 are connected with metal foil exposed parts 41c, 42c. The collector plates 21, 31 respectively have body parts 22, 32 disposed between a battery lid 3 and the wound electrode group 40. The insulator 5 includes second insulation sheets 15, 16 covering the metal foil exposed parts 41c, 42c and the collector plates 21, 31. The second insulation sheets 15, 16 respectively have first insulation parts 15d, 16d protruding along a wound axis direction of the wound electrode group 40 and respectively disposed between the wound electrode group 40 and the body part 22 and between the wound electrode group 40 and the body part 32. Cutout parts 15f, 16f are respectively provided at tips of the first insulation parts 15d, 16d. |
