NOVELTY - An exterior material (1) comprises outer side layer (10), thermoplastic resin unstretched-film layer as inner side layer (3), and metal foil layer (4) which is arranged between outer side layer and inner side layer. Outer side layer has heat resistant resin film layer (2) and vapor deposition layer (7) laminated on inner surface and/or outer surface of heat resistant resin film layer.    USE - An exterior material for electrochemical devices (claimed). Uses include but not limited to lithium-polymer battery, lithium-ion battery, lithium-ion capacitor, electric double layer capacitor used for portable apparatuses, such as smart phone and tablet, power supplies, such as hybrid vehicle and electric vehicle, battery and capacitor used for electrical storage of wind power generation, photovoltaic power generation, and night-time electricity.    ADVANTAGE - Vapor deposition layer can suppress penetration of moisture content from outside, diffusion to exterior of electrolyte solution, and leakage. The exterior material has excellent water barrier property and excellent electrolyte solution diffusion prevention property, attaining sufficient thin film formation and weight reduction. Electrochemical device externally equipped using the exterior material are thinned and reduced in weight which can improve weight energy density and volume energy density of an electrochemical device.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for electrochemical device comprising electrochemical device main-body part and exterior material for electrochemical devices in which electrochemical device main-body part is externally equipped with exterior material.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional diagram of the exterior material for electrochemical devices.    Exterior material for electrochemical devices (1)    Heat resistant resin film layer (2)    Thermoplastic resin unstretched-film layer as inner side layer (3)    Metal foil layer (4)    Vapor deposition layer (7)    Outer side layer (10)