EXTERIOR MATERIAL FOR POWER STORAGE DEVICE

To provide an exterior material for a power storage device that has excellent moldability, can ensure good printability on the surface, and also has excellent solvent resistance.SOLUTION: An exterior material for a power storage device includes a base material layer made of heat-resistant resin, a sealant layer as an inner layer, and a metal foil layer placed between the base material layer and the sealant layer, a protective layer is laminated on the surface of the base material layer opposite to the metal foil layer side, the protective layer includes a composition including a polyester resin of 40% by mass or more, formed from a polyester polyol having a number average molecular weight of 5,000 to 50,000 and having at least a hydroxyl group or a carboxyl group independently at each end, and a polyfunctional isocyanate curing agent containing at least an aliphatic polyfunctional isocyanate compound.SELECTED DRAWING: Figure 1 【課題】成形性に優れ、表面における良好な印字性を確保できると共に、耐溶剤性にも優れた蓄電デバイス用外装材を提供する。【解決手段】耐熱性樹脂からなる基材層と、内側層としてのシーラント層と、基材層とシーラント層の間に配置された金属箔層と、を含み、基材層における金属箔層側とは反対側の面に保護層が積層され、保護層は、少なくとも両末端のそれぞれに独立に、水酸基またはカルボキシル基を有する数平均分子量が５０００～５００００のポリエステルポリオールと、少なくとも脂肪族系多官能イソシアネート化合物を含む多官能イソシアネート硬化剤により形成されたポリエステル樹脂を４０質量％以上含有する構成とする。【選択図】図１