FIG. 6 illustrates a state in which the concave-convex wave-shaped crest ridge or trough furrow formed in the laminate film, is continuous to have a circular shape.

A plurality of wave-shaped crest ridges or trough furrows are formed to have concentric circular shapes (concentric crest ridges or trough furrows 111), and the laminate film is dotted with the circular shapes. Since the wave-shaped, crest ridges or trough furrows are formed to have circular shapes, the top surface of protrusion 103 of the laminate film on the upper side extends in every direction such that wrinkling or cracking does not appear, even when the battery is curved in any direct ion. In the present embodiment, although an example in which ridges and furrows are continuous to have circular shapes is described, the ridges may be continuous to have a polygonal shape such as a triangular shape or a quadrangular shape, as a variation.

FIG. 7 illustrates a mode in which convex shapes are formed, in the laminate film. A plurality of convex shapes 112 are formed on the laminate film and are dotted around.

In the present embodiment, the top surface of protrusion 103 of the laminate film on the upper side also extends in every direction such that wrinkling or cracking does not appear, even when the battery is curved in any direction. In the present embodiment, especially, convex shapes are formed; however, concave shapes or concave and convex shapes may be dotted around.