MULTILAYER STRUCTURE FOR BATTERY ENCASEMENT

The present invention is related to a battery module packaging comprising a multilayer structure 1, said structure comprising:- an inner polymer layer 2, an outer polymer layer 4 and an aluminum foil 5 sandwiched between the inner polymer layer 2 and the outer polymer layer 4, or- an inner polymer layer 2, an outer polymer layer 4, an aluminum foil 5 sandwiched between the inner polymer layer 2 and the outer polymer layer 4 and an intermediary layer 3 sandwiched between aluminum foil 5 and inner polymer layer 2;wherein:- inner polymer layer 2 comprises a chromium based protective layer 6 on one side, facing the aluminum foil 5 or intermediary layer 3; and/or- aluminum foil 5 comprises a chromium based protective layer 6 on one side, facing inner polymer layer 2 or intermediary layer 3; and/or- intermediary polymer layer 3 comprises a chromium based protective layer 6 on at least one of its sides, facing either aluminum foil 5 and/or inner polymer layer 2; andwherein:- the chromium based protective layer 6 is a metallic chromium layer comprising trivalent chromium, or is a trivalent chromium layer;- a modified polyolefin tie layer 8 is deposited between the aluminum foil 5 and polymer layer 2 or between aluminum foil 5 and polymer layer 3 and between polymer layers 2 and 3, wherein at least one of said aluminum foil 5 and one of said polymer layers 2 and 3 comprises protective layer 6; andwherein in use:- the inner polymer layer 2 is in direct contact with the cell part of the battery;- the outer polymer layer 4 is in contact with a hardware element of the battery.