Power storage device and method for manufacturing power storage device

A manufacturing method of a power storage device including an electrode group including a positive electrode, a negative electrode, and a separator, the manufacturing method comprising the steps of:

• (i) forming the electrode group by stacking the positive electrode, the negative electrode, and the separator, with the separator disposed between the positive electrode and the negative electrode;
• and
• (ii) heating at least a portion of the electrode group, wherein
• the positive electrode includes a positive electrode current collector, and a positive electrode active material layer disposed on the positive electrode current collector,
• the negative electrode includes a negative electrode current collector, and a negative electrode active material layer disposed on the negative electrode current collector,
• in the step (i), the electrode group is formed so that a portion of the separator becomes a protruding part protruding from a region in which the positive electrode active material layer and the negative electrode active material layer are opposed to each other,
• the separator includes a positive-electrode-side surface located toward the positive electrode adjacent to the separator, and a negative-electrode-side surface located toward the negative electrode adjacent to the separator,
• the separator includes a substrate, and a first heat-resistant layer formed on a surface of the protruding part, and,
• in the step (ii), at least a portion of the protruding part is heated to curl the at least a portion of the protruding part.