Battery having laminated wrapper member which includes gas venting passageway

Claim 1

AN IMPROVEMENT IN A BATTERY COMPRISING A. AT LEAST ONE CELL, THE CELL COMPRISING A POSITIVE ELECTRODE SEPARATED FROM A NEGATIVE ELECTRODE BY AN ELECTROLYTECONTAINING LAYER, THE CELL BEING SEALED AT ITS PERIPHERY BY A LIQUID AND MOISTURE IMPERVIOUS SEAL, AND B. AT LEAST ONE WRAPPER MEMBER SECURED TO THE CELL AND EXTENDING OVER AT LEAST SOME OF THE AREAS ENCLOSED BY THE PERIPHERAL SEAL, THE WRAPPER MEMBER COMPRISING THE COMBINATION OF I. AN INNER LAYER WHICH FACES THE CELL AND WHICH IS PERVIOUS TO GASES GENERATED BY THE CELL, AND II. AN OUTER LAYER WHICH IS IMPERVIOUS TO LIQUIDS AND WHICH IS LESS PERVIOUS THAN THE INNER LAYER TO THE GASES GENERATED BY THE CELL, WHEREIN THE IMPROVEMENT PROVIDES A GAS:VENTING PASSAGEWAY, THE IMPROVEMENT COMPRISING THE LAMINATION OF SOME BUT NOT ALL OF THE COEXTENSIVE SURFACES OF THE INNER AND OUTER LAYERS, THE UNLAMINATED PORTONS OF THE TWO LAYERS PROVIDING A PASSAGEWAY BETWEEN THE TWO LAYERS FOR THE VENTING OF GASES GENERATED BY THE CELL, THE PASSAGEWAY BEING SITUATED BEYOND THE INSIDE FACE OF THE INNER LAYER SO THAT GASES GENERATED BY THE ELL MUST FIRST PASS THROUGH THE FIRST LAYER BEFORE REACHING THE PASSAGEWAY, THE PASSAGEWAY COMMUNICATING WITH THE EXTERIOR OF THE BATTERY.