Electrode Assembly and Method for Manufacturing the Same

A method for manufacturing an electrode stack, the method comprising:

• a stacking step of alternately stacking electrodes and separators to form an electrode stack, wherein the electrode stack is formed of negative electrodes comprising negative electrode extension parts that are portions that extend beyond first peripheral edges of positive electrodes and separators on one end of the electrode stack and the positive electrodes comprising positive electrode extension parts that are portions extend beyond second peripheral edges of the negative electrodes and the separators on another end of the electrode stack opposite to the one end;
• a negative electrode welding step of welding the plurality of negative electrode extension parts to each other;
• and
• a positive electrode welding step of welding the plurality of positive electrode extension parts to each other.

A secondary battery comprising a single electrode assembly in which a plurality of negative electrodes and a plurality of positive electrodes are stacked alternately and repeatedly and separators are disposed between the negative electrodes and the positive electrodes, the secondary battery comprising:

• 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 another 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 another end of the electrode assembly and electrically connecting the plurality of the negative electrodes.