The present invention provides a single electrode assembly, in which a plurality of negative electrodes and positive electrodes are stacked alternately and repeatedly, and separators are disposed between the plurality of negative electrodes and positive electrodes, the electrode assembly including: a negative electrode tab part formed on one end of the electrode assembly and extending from the plurality of negative electrodes; a positive electrode bus bar spaced apart from the negative electrode tab part on the one end of the electrode assembly and electrically connecting the plurality of the positive electrodes; a positive electrode tab part formed on the other end of the electrode assembly opposite to the one end and extending from the plurality of positive electrodes; and a negative electrode bus bar spaced apart from the positive electrode tab part on the other end of the electrode assembly and electrically connecting the plurality of the negative electrodes.