An alkaline cell having a flat housing, preferably of cuboid shape. The housing may be laser welded closed with a metal cover inserted as a part of an end cap assembly. A portion of an insulating seal may be held compressed between a sleeve extending from the metal cover and an anode current collector nail within the end cap assembly. The housing may include a vent mechanism, preferably a grooved vent, which can activate, when gas pressure within the cell reaches a threshold level typically between about 250 and 800 psig (1724x103 and 5515x103 pascal gage). The cell can have a supplemental laser welded vent which may activate at higher pressure levels.
