Embodiments of the present application disclose a battery to reduce the volume of the battery, improve the energy density of the battery, and further improve the bottom molding effect of the battery, as well as the safety performance and service life of the battery. The battery comprises an electrode assembly and a package film for packaging the electrode assembly, the package film including a folding portion, the folding portion including a first segment attached to the end face of the electrode assembly and a second segment connected to the first segment. The first segment is arranged between the second segment and the electrode assembly, and the second segment includes a multilayer package films.