Patent ID: 9728763
Date: 2017-08-08
CPC Classifications: H01M,Y02E

Claim:
1. A current interruption device configured to interrupt a current path connecting an external terminal provided on a casing and an electrode assembly accommodated within the casing when an internal pressure of the casing rises above a predetermined level, the current interruption device comprising: a first conductive member electrically connected to the external terminal; a second conductive member disposed to face the first conductive member, and electrically connected to the electrode assembly; an insulating seal member sealing an interspace between the first conductive member and the second conductive member; and an insulating cover holding the first conductive member, the second conductive member and the seal member, wherein the first conductive member and the second conductive member conduct electricity between each other to form part of the current path when the internal pressure of the casing is a predetermined level or below, and separate each other to interrupt the current path when the internal pressure of the casing rises above the predetermined level, the seal member comprises a first contact portion that is in contact with a vicinity of an outer circumferential edge of the first conductive member and a second contact portion that is in contact with a vicinity of an outer circumferential edge of the second conductive member, and the seal member partitions a space surrounded by the first conductive member, the second conductive member and the cover into a first space which is inside the first contact portion and the second contact portion and a second space which is outside the first contact portion and the second contact portion, the second space communicates with a space within the casing, the first space is sealed from the space within the casing by the seal member, in a plan view of the first conductive member, the second conductive member and the seal member, when the first contact portion and the second contact portion are positioned within a range where the first conductive member and the second conductive member are facing each other, the seal member is positioned in an entire area outside of the first contact portion and the second contact portion within the range where the first conductive member and the second conductive member are facing each other, and when the first contact portion and the second contact portion are not positioned within the range where the first conductive member and the second conductive member are facing each other, the seal member is positioned outside of the range where the first conductive member and the second conductive member are facing each other, and the cover is disposed along the outer circumferential edge of the first conductive member, and disposed outside of the second space, and the seal member is further in contact with the cover.