US Patent 9786872 Flexible secondary battery

A flexible secondary battery includes: an electrode assembly including a first electrode layer, a second electrode layer, and a separator between the first electrode layer and the second electrode layer; a gasket having flexibility and surrounding edges of the electrode assembly; a first sealing sheet attached to a first surface of the gasket; and a second sealing sheet attached to a second surface of the gasket facing away from the first surface, wherein an uneven pattern is at a bendable area of the gasket.