Patent ID: 8486546
Filing Date: 2013-07-16
Classification: H01M,Y02E

Abstract:
1. A cap assembly for a battery that includes a bare cell with an electrode, the cap assembly comprising: a plate that is adapted to be electrically connected to the electrode of the bare cell; a vent member that includes a protrusion that is physically connected to the plate so as to be electrically connected to the electrode; and a positive temperature coefficient (PTC) thermistor electrically connected to the vent member, the PTC thermistor being ring shape, wherein the vent member defines a first and a second circular notches and a third cross notch that intersects the first and second circular notches, wherein the first and second circular notches extend around the protrusion and the cross notch extends outward from the first circular notch through the second circular notch so as to intersect the second circular notch and further extend outward from the second circular notch and wherein the depth of the cross notch exceeds the depth of the first and second circular notches and the depth of the cross notch is selected to permit flexing of the vent member at a first pressure and the depth of the second circular cross notch is selected to result in the vent member bursting at a second pressure greater than the first pressure.