Patent ID: 8252457

Claim:
A battery cell comprising: a case including a lid member having an upper surface, the lid member having a hole; an electrode unit contained in the case; an insulating member fitted into the hole; and an electrode terminal, one end of which is connected to the electrode unit, and the other end of which is passed through the insulating member and is extended out of the case through the hole, wherein: the electrode terminal has an exposed portion that is further extended out of the insulating member outside the case; the insulating member includes: a first insulating portion interposed between the electrode terminal and the hole, and a second insulating portion formed along a surface of the electrode terminal that is extended out of the case through the hole; the insulating member further includes a third insulating portion that is provided between the first insulating portion and the second insulating portion; a recess is formed in a top surface of the third insulating portion; and the top surface of the third insulating portion faces in substantially the same direction as the upper surface of the lid member.