Electrochemical cell packaging material

An electrochemical cell packaging material for housing an electrochemical cell body, the electrochemical cell body including a positive electrode comprising a positive-electrode active material and a positive-electrode collector, a negative electrode comprising a negative-electrode active material and a negative-electrode collector, and an electrolyte filled between said positive electrode and said negative electrode;

• and
• sealing said electrochemical cell body by heat-sealing of a peripheral edge part of the electrochemical cell packaging material;
• said electrochemical cell packaging material characterized in that
• the electrochemical cell packaging material is a multilayer film having a structure formed by laminating at least a base layer, an adhesive layer, a metal foil layer, and a heat-sealable layer in this order;
• in said peripheral edge part, parts of said heat-sealable layer arranged as an innermost layer are made to face each other and are heat sealed together;
• said adhesive layer which bonds together said base layer arranged as an outermost layer and said metal foil layer includes an identification mark;
• and
• said identification mark is composed of an adhesive to which a color pigment is added to give a solids content of 5 wt % or greater and 30 wt % or less.