SECONDARY BATTERY COMPRISING CURRENT INTERRUPT DEVICE

摘要

In a secondary battery (10) suggested herein, when a gas pressure in a battery case (12) is increased to or above a specified level and a current interrupt valve (26) is consequently raised to a connecting terminal (21) side, a thinned section (71) is broken around a portion that is joined to the current interrupt valve 26, the connecting terminal (21) and an electrode body are electrically interrupted from each other. An insulant (27) is disposed in a portion where the thinned section (71) is broken, and is interposed between both edges of the broken thinned section (71) after the thinned section (71) is broken.

主权项

1. A secondary battery comprising:
a battery case; an electrode body that is housed in the battery case; a connecting terminal that is provided in the battery case; and a current interrupt device that includes a current interrupt valve, a current collector, and an insulant, electrically connects the connecting terminal to the electrode body, and electrically cuts off the connecting terminal from the electrode body when a gas pressure in the battery case is increased to or above a specified level, wherein the current interrupt valve is formed of a conductive thin plate and is attached to an opening of the connecting terminal on an inner side of the battery case so as to cover the opening, the current collector includes: a thickened section that is provided in a position to face a surface of the current interrupt valve on the inner side of the battery case; and a thinned section that is formed in a center of the thickened section and joined to the current interrupt valve, when the gas pressure in the battery case is increased to or above the specified level, the thinned section is broken around a portion that is joined to the current interrupt valve along with deformation of the current interrupt valve, and the connecting terminal is electrically interrupted from the electrode body, and the insulant is disposed in a portion where the thinned section is broken and is interposed between both edges of the broken thinned section after the thinned section is broken.