Battery case with edge seal

摘要

A battery case for a battery containing swellable cellulose separators including case members having opposed undulating mating surfaces and a rim and groove sized to space the surfaces a predetermined distance apart to form a gripping channel such that the outer portion of a stack of dry separators occupies at least 80% but no more than 98% of said channel. On injecting liquid electrolyte into the case, the separators swell and are securely gripped by said undulations and mating surface.