A battery system has a casing forming an interior chamber. The casing is comprised of a polymer. The battery system has a chemically active material contained by the interior chamber. The polymer withstands heat generated by the chemically active material....

A sealed storage battery includes a battery case containing a group of electric power-generating elements each comprising a positive electrode, a negative electrode and a separator, a battery case lid (14) closing an opening in the battery case to seal the...