Method for welding electrode assembly

A method for welding an electrode assembly, comprising:

• stacking a plurality of electrodes to manufacture the electrode assembly;
• attaching a buffer tab to a surface of an outermost electrode tab of the electrode assembly;
• welding a lead such that a plurality of electrode tabs and the lead are in contact with each other to dispose the buffer tab therebetween;
• gathering and pre-welding the plurality of electrode tabs such that each electrode tab of the plurality of electrode tabs is bonded to each other, after the attaching of the buffer tab and before the welding of the lead;
• and
• cutting an end portion of the buffer tab and end portions of the plurality of electrode tabs so that an end of the buffer tab and ends of the plurality of electrode tabs are aligned with each other, after the pre-welding and before the welding of the lead,
• wherein the electrode assembly comprises a stacked plurality of electrodes comprising the lead welded to the plurality of electrode tabs,
• wherein each electrode tab of the plurality of electrode tabs protrudes in one direction from the plurality of electrodes, and
• wherein the buffer tab covers a region of the outermost electrode tab in which the plurality of electrode tabs are stacked and contact each other, and further covers a region of the outermost electrode tab in which the plurality of electrode tabs do not contact each other.