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 (1724.times.10.sup.3 and
5515.times.10.sup.3 pascal gage). The cell can have a supplemental laser
welded vent which may activate at higher pressure levels.