Provided is a packaging element including a polymer layer and having a thickness of between 10 and 200 micro meter; wherein the packaging element being for use in providing an essentially sealed, void-free enclosure of an energy storage device, and wherein the polymer is selected from: poly(para-xylylene), poly-m-xylylene adipamide, dielectric polymer, silicone-based polymer, polyurethane, acrylic polymer, rigid gas impermeable polymer, fluorinated polymer, epoxy, polyisocyanate, PET, silicone rubber, silicone elastomer, polyamide and any combinations thereof.