A battery cell comprising: an electrode assembly; a cell exterior material configured to accommodate the electrode assembly and comprising an upper exterior material and a lower exterior material; a lead part extending between the upper exterior material and the lower exterior material from the electrode assembly and led out of the cell exterior material; and characterized by a cutting part positioned on upper and lower ends of the lead part and configured to cut and disconnect the lead part when overcharge occurs, wherein the cutting part comprises: a first cutter part positioned in the direction toward the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a first cutting blade; a second cutter part positioned on the side of the first cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the lower exterior material and accommodating a second cutting blade; and a third cutter part positioned on the side of the second cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a third cutting blade, wherein, when an overcharge occurs, the battery cell expands and a distance between the upper exterior material and the lower exterior material increases, and the lead part is thereby cut, wherein the first cutting blade of the first cutter part and the third cutting blade of the third cutter part are respectively provided on lower end portions of the frames of the first cutter part and the third cutter part, and positioned at a lower portion of the lead part when the cutter part is configured, and wherein the second cutting blade of the second cutter part is formed on an upper end portion of the second cutter part and positioned at an upper portion of the lead part when the cutting part is configured. an electrode assembly; a cell exterior material configured to accommodate the electrode assembly and comprising an upper exterior material and a lower exterior material; a lead part extending between the upper exterior material and the lower exterior material from the electrode assembly and led out of the cell exterior material; and characterized by a cutting part positioned on upper and lower ends of the lead part and configured to cut and disconnect the lead part when overcharge occurs, wherein the cutting part comprises: a first cutter part positioned in the direction toward the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a first cutting blade; a second cutter part positioned on the side of the first cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the lower exterior material and accommodating a second cutting blade; and a third cutter part positioned on the side of the second cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a third cutting blade, wherein, when an overcharge occurs, the battery cell expands and a distance between the upper exterior material and the lower exterior material increases, and the lead part is thereby cut, wherein the first cutting blade of the first cutter part and the third cutting blade of the third cutter part are respectively provided on lower end portions of the frames of the first cutter part and the third cutter part, and positioned at a lower portion of the lead part when the cutter part is configured, and wherein the second cutting blade of the second cutter part is formed on an upper end portion of the second cutter part and positioned at an upper portion of the lead part when the cutting part is configured. a first cutter part positioned in the direction toward the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a first cutting blade; a second cutter part positioned on the side of the first cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the lower exterior material and accommodating a second cutting blade; and a third cutter part positioned on the side of the second cutter part in the direction opposite the electrode assembly, and comprising a frame attached to the upper exterior material and accommodating a third cutting blade, wherein, when an overcharge occurs, the battery cell expands and a distance between the upper exterior material and the lower exterior material increases, and the lead part is thereby cut, wherein the first cutting blade of the first cutter part and the third cutting blade of the third cutter part are respectively provided on lower end portions of the frames of the first cutter part and the third cutter part, and positioned at a lower portion of the lead part when the cutter part is configured, and wherein the second cutting blade of the second cutter part is formed on an upper end portion of the second cutter part and positioned at an upper portion of the lead part when the cutting part is configured.