In some example embodiments, a battery described herein includes a plurality of foldable cells, that when folded takes the form of an asymmetric battery that can utilize available space within a portable electronic device and further is configured to present a curved form factor. In some example embodiments, the apparatus includes a first set of cells and a second set of cells. The first set of cells and the second set of cells are disposed on a sheet that is foldable such that the first set of cells and the second set of cells form a folded battery configuration.