Abstract: And end cap assembly and venting system therein for closing and sealing the open end of a cell housing. The end cap assembly comprises a sealing disk underlying an end cap, and a metal support disk between the end cap and the sealing disk. The metal support disk has a plurality of primary vent apertures and a plurality of secondary vent apertures through its surface. The primary vent apertures are spaced apart along a path located at a greater distance from the central longitudinal axis of the metal support disk than the secondary vent apertures. The insulating sealing disk may have a thinned portion therein forming an rupturable membrane circumventing the central hub of the sealing disk. The insulating sealing disk may have protrusions emanating from its top surface to deflect the membrane during rupture. The venting system releases internal gases rapidly from the cell in the event of an abusive or short circuit discharge.

Abstract: And end cap assembly and venting system therein for closing and sealng the open end of a cell housing. The end cap assembly comprises a sealing disk underlying an end cap, and a metal support disk between the end cap and the sealing disk. The metal support disk has a plurality of primary vent apertures and a plurality of secondary vent apertures through its surface. The primary vent apertures are spaced apart along a path located at a greater distance from the central longitudinal axis of the metal support disk than the secondary vent apertures. The insulating sealing disk may have a thinned portion therein forming an rupturable membrane circumventing the central hub of the sealing disk. The insulating sealing disk may have protrusions emanating from its top surface to deflect the membrane during rupture. The venting system releases internal gases rapidly from the cell in the event of an abusive or short circuit discharge.

Abstract: A primary alkaline battery includes a cathode having manganese dioxide and carbon particles, an anode, a separator and an alkaline electrolyte. The carbon particles include expanded graphite particles and non-expanded graphite particles. The expanded graphite particles have a kerosene absorption greater than about 2.7 milliliters per gram.