Disclosed is an electrode assembly with a structure in which a plurality of electrode plates are stacked while a separator is interposed between a positive electrode plate and a negative electrode plate, each of the electrode plates including an electrode tap that externally protrude from one side thereof to form a tap-lead coupler and at least two or more fixing parts that externally protrude from each of electrode plate by a length of 10% to 50% of a length of the electrode tap from the one side and/or the other side, wherein fixing parts with the same polarity, which are positioned in parallel to each other in up and down directions, are bonded to each other to maintain a stack interval between the electrode plates while the electrode plates are stacked.