An electrode assembly for a polymer secondary battery cell, comprising: a cell stack part (100, 100') defined by stacking at least one radical unit (110, 110') having a four-layered structure in which a first electrode, a first separator, a second electrode and a second separator are stacked in turn, wherein at least one of the first electrode and the second electrode has a size corresponding to 99.7% to 100% of a size of the first separator or the second separator and thus is aligned to be coincided with or close to an end of the first separator or the second separator, wherein the cell stack part (100, 100') further comprises a first auxiliary unit which is stacked on a first terminal electrode as the first electrode disposed at the uppermost side or the lowermost side thereof, and when the first electrode is a cathode and the second electrode is an anode, the first auxiliary unit is defined by stacking the separator, the anode, the separator and the cathode in turn from the first terminal electrode or by stacking the separator, the anode and the separator in turn from the first terminal electrode, and when the first electrode is the anode and the second electrode is the cathode, the first auxiliary unit is defined by stacking the separator and the cathode in turn from the first terminal electrode, wherein in the radical unit, at least one of the first electrode and the second electrode is defined so that one of the width and the length thereof is the same as that of the first separator or the second separator, and the other one is smaller than that of the first separator or the second separator, wherein the cathode of the first auxiliary unit comprises a collector and an active material coated on only one surface of the collector, said surface facing the radical unit (110, 110'). a cell stack part (100, 100') defined by stacking at least one radical unit (110, 110') having a four-layered structure in which a first electrode, a first separator, a second electrode and a second separator are stacked in turn, wherein at least one of the first electrode and the second electrode has a size corresponding to 99.7% to 100% of a size of the first separator or the second separator and thus is aligned to be coincided with or close to an end of the first separator or the second separator, wherein the cell stack part (100, 100') further comprises a first auxiliary unit which is stacked on a first terminal electrode as the first electrode disposed at the uppermost side or the lowermost side thereof, and when the first electrode is a cathode and the second electrode is an anode, the first auxiliary unit is defined by stacking the separator, the anode, the separator and the cathode in turn from the first terminal electrode or by stacking the separator, the anode and the separator in turn from the first terminal electrode, and when the first electrode is the anode and the second electrode is the cathode, the first auxiliary unit is defined by stacking the separator and the cathode in turn from the first terminal electrode, wherein in the radical unit, at least one of the first electrode and the second electrode is defined so that one of the width and the length thereof is the same as that of the first separator or the second separator, and the other one is smaller than that of the first separator or the second separator, wherein the cathode of the first auxiliary unit comprises a collector and an active material coated on only one surface of the collector, said surface facing the radical unit (110, 110').